Version 1.4 March 12, 1996by Larry Soo (larry_soo@mindlink.bc.ca) ************* DISCLAIMER: While every effort has been taken to insure the accuracy of the information contained in this FAQ list compilation, the author and contributors assume no responsibility for errors or omissions, or for damages resulting from the use of the information contained herein. The information below may be reproduced in any way PROVIDED that credit is given to the writers and the maintainer; and that it is not published in book or magazine form without the prior written permission of the maintainer; that the maintainer receives, without needing to ask, a FREE copy of the final material; and that no changes are made (except for formatting) without the express permission of the maintainer (larry_soo@mindlink.bc.ca -- Larry Soo) ************************** Notes: Some of the following information was obtained from the Chrysler FAQ list (maintained by David Zatz [valiant@mordor.com]). This is the first version of this FAQ so I'd be grateful for any suggestions/information which you can contribute to make this a more valuable resource for Jeep Wrangler/YJ owners. Version Changes: 1.1 Original Version 1.2 October 27, 1995 1.10 Added length of new bolts required for the 1" body lift. 5.45 Added a trouble shooting tip: Engine Quits Intermittently 5.55 Added a tech tip for fixing the "high idle on start up" problem. 6.00 Added a new, FREQUENTLY ASKED QUESTIONS where I answer the most common Wrangler questions. This is primarily for offroading novices. 1.3 January 8, 1996 Added: 1.15 Full Roll Cage 1.35 Spring-Over Conversion - Experiences & Opinions 3.75 Ring & Pinion Gear Upgrade 3.76 Ring & Pinion Gear Installation Tips 3.85 Transmission Bushing - It's Supposed to be Loose! Modified: 3.10 Axle Upgrade Options Information was added about swapping Ford Bronco axles onto a YJ. 3.60 MIT Installation Added my own experiences regarding such an installation. 1.4 March 12, 1996 * Moved to an HTML format! This is a great benefit for readers who have HTML viewers or WEB browsers. All section numbers have been removed. * New Items - Airbox Intake Re-routing - Removing the Steering Stabilizer - More stuff on Rough Idling - Shackle Reversals - Brake Line Extensions - 4:1 Transfer Case Conversion - Removing the Clutch Pilot Bearing - Transmission Installation Trick - Attaching a Skidplate/Crossmember - Additional info on the differences between the various traction-adding devices, see "Lockers or Limited Slip Differentials" - Rear Main Oil Seal - Installation - Web Address for Terry Howe's Drivetrain Page - Underhood Welder - Make Your Own ====================================================== TABLE OF CONTENTSEngineDiagnosing Electronic Ignition Systems Diagnosing Problems With Computer-Controlled Carburetors High Idle When Starting (4.0L) Rear Main Oil Seal - Installation Runs & Sputters After Turning Off DrivetrainAdjusting the Steering Stops -- Tires Rub Against Springs Automatic Transmission Adjustments Automatic Transmission Fluid - What Kind to Use Clutch Pilot Bearing - How to Remove Lockers or Limited Slip Differentials Ring and Pinions Ring & Pinion Gear Installation Tips Should I Install a Locker in the Front or the Back? Torque Converters - Offroad Considerations Transfer Case 4-1 Gear Conversion Transmission Bushing - It's Supposed to be Loose! Transmission Installation Trick Web Page for Drivetrain Info (Terry Howe's Page) SuspensionSpring-Over Conversion - Experiences & Opinions What Tires Fit Under What Lift? What is Involved in Lifting My Wrangler? BrakesChassisAttaching a Skidplate/Crossmember Fuel Gauge Sending Unit Not Working Removing the Steering Stabilizer BodyBody Lift in Comparison to Other Lifts Windshield Leaks & Replacing the Glass TiresAccessoriesAir Conditioner Troubleshooting Underhood Welder - Make Your Own MiscHow to Deal With Chrysler Corp . Loctite vs. Anti-Seize Compound What the Heck is a Banana-Rating [tm] ?? What is Required to Make my YJ Offroad-Worthy? ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Underhood Welder - Make Your Own >Just picked up a 150 amp alternator cheep. >How do you connect up for welding? Install it in the 4-WHEELER wire a switch in to supply full voltage to the rotor, include a method of removing the battery from its output lead, install a voltmeter on the output, install a micro adjustable hand throttle, get some standard welding whip lead and a few good plug & connectors, a ground clamp and stinger, a hood some gloves and some smaw rod (e7018, 5/32" works great). Start the 4-WHEELER, isolate the alternator from the battery, flip the full voltage switch on to the alt rotor, watch the voltmeter while bringing the engine rpm up (2500 rpm or so) until the open circuit voltage is about 75 volts, strike an arc and watch the voltage drop to about 30 volts. It's great fun, and you can't have this fun until you get started doing it. Don't try to figure it all out in advance on paper. If the diodes blow, replace them and add another set in parallel. Enjoy Life....... OOPS, got a little carried away here, answered too many questions at one time ;)....... >What size wire leads? see above. >How do you vary the amperage or do you? see above, use the micro adjustable hand throttle. Randy Peterson RKP2@PGE>COM '82 CJ-7, looking for an 125a ford (motocraft) alternator or two to weld with. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Rear Main Oil Seal - Installation INSTALLING REAR MAIN OIL SEAL ON 4.0 (or 304 or 258) The rear main oil seal went on my Comanche 4.0 at about 40K miles. It went again at about 65K (I used to be rough on it). It is a fairly simple operation to replace. The first time it tried it, I followed the Chilton's manual and removed the tranny--BIG mistake--it wasn't needed. The next time I spent about two hours on it but I had since done it on my CJ as well. I 't have to move any exhaust--you may have to on a YJ. -- Drain Oil. Remove the oil pan -- scrape old seal off of the block and oil pan -- clean out oil pan -- scraping the seal is easier with Permatex gasket remover -- it cuts times in half--you'll need to use it two or three times but it's easier than elbow grease. -- Remove rear crankshaft bearing cap (two bolts) and loosen next two sets. -- The rear main oil seal is two pieces--one piece will be in the first bearing cap. The other is in the block. Take a small pindrift or screwdriver and carefully tap one end of the concealed seal. It should loosen after a couple of taps. Take care to notice the way the old seal faces so you reinstall the new one properly. -- When the other end comes out enough, grab it with a pair of pliers and pull it out. To install new one, put oil on inside lip and some dishwashing soap on outside. It takes some practice to get this part right (I shredded two seals before I got it right) -- but place new seal on bottom of crankshaft in proper position to rotate it into the groove in the block. The end that is to go into the block should be pushed to be as flush with the crankshaft as possible -- then rotate the seal into the block keeping it as flush with the crankshaft as possible--if you're not careful, you'll scrape some rubber off the top of the seal--if you do--get another seal because it probably won't seal. -- Seal should be nearly flush with block when you're done. Put other half of seal in bearing cap and put some sealant (I used blue-glue) on the surface where the cap meets the block. Don't get too much on it and keep it off the seal part-make sure you get a little on the part where the seals meet. -- Torque crankshaft bolts back and install the one with the seal in it last. -- Reinstall oil pan with new gasket--part cost about $20 for both seals. Good luck!! - DaveO ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Attaching a Skidplate/Crossmember >The skid-plate/crossmember on my 76 CJ-7 has 2 of >the bolts broken off in the frame both on one >side.) I have a temporary fix right now that >involves foundation anchors (don't ask!). >I have tried left hand drill bits and >easy-outs with no success. >The only alternative left is to drill out the >holes and put a bolt in it. > >The problem: this section of the frame is boxed >and I can't get a bolt in it! Any suggestions >or people with similar problems? OPTION 1. : Drill completely thru the frame and thru bolt the whole mess. Also good for tranny swaps when no holes line up. OPTION 2 : Drill and tap exactly where the broken bolt are now. Sometimes works, sometimes won't center on the broken bolt. This is usually easier than fighting with an EZ out. And if you break an EZ out, your F'ed caused they're hardened steel. OPTION 3 : Cut, grind, torch or hole-saw a small hole or slot on the INSIDE (thinner and easier to cut) of the frame and drop in nuts and bolt as needed. Watch out for the fuel line on the pass side if torching... OPTION 4 : Get some small square U-bolts say 3/8" thread, 1.5" between centers, 2" long. Drill two oversized holes to match the spacing and snake these u-bolts around thru one of the oversized holes and out the other. Bolt with washers and nuts. I Have done every one of these and they all work. IF you have a not-so-clean frame, burn holes on the inside boxed section and drop your bolts in. I didn't have the heart to do this to mine, so I thru-bolted all six on the skid plate. - Rick Boiros ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Transmission Installation Trick I was discussing my near future tranny swap plans (yes, yes, yes, yes) with a friend and he gave me an interesting tip that ya'll may or may not have heard. He suggested removing one bolt then going immediately to the hardware store and purchasing as many as you need of the same size grade 8 bolt about 8 inches longer than the origional. Then grind or cut off the head of all the bolts. As you remove a tranny bolt insert one of these long threaded rods. This acts as a guide to help you center the tranny to get it off and then back on again. I've only helped install a tranny before but that was deffinately the hardest part, just lining everything up. Like I said I haven't tried this before and it may be a common trick but it sounded like a good one. John Kane ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Clutch Pilot Bearing - How to Remove >Does anybody have a good method to remove the pilot >bearing from a '93 YJ with a 4.0L? If it is a bushing and not a roller bearing, here is a very cheap removal method that has worked for me. Don't laugh too hard, it DOES work! Get 1) a smooth piece of round stock (rod) that is a sliding fit into hole of the pilot bushing. 2) A small hammer 3) A *bunch* of toilet paper soaking in a dish of water. The paper needs to be dripping wet as this method depends on the water to work. 4) A pair of small needle nose pliers. Stuff wet paper into the hole of the pilot bushing. When the cavity behind the pilot bushing gets full, start tamping the wet paper into the pilot bushing hole with the round stock and the hammer. Keep adding wet paper so that as you hammer on the round stock, the round stock only goes into the pilot bushing hole 1/2 inch or so. After a seemingly endless amount of wet paper, the pilot bushing will start being pushed out. When the pilot bushing is out, take the needle nose pliers and pull out all of the toilet paper. The paper will be VERY tightly packed, so it will require some effort to remove it all. It is easy to leave some paper behind. so get a mirror and look to make doubly sure you have removed it all. (the method is cheap, so there has to be some drawback :-) I have been told that if you get really violent with the hammer, it is possible to split the crank. I have used this many times and so far, the only thing to split has been people's sides. Eric >>I don't know if it will work, but the Hick's >>catalog suggests packing the inside and back >>of the bearing with grease, and then hammering a >>close-fitting dowel into the I.D. of the bearing. >>The hydraulic pressure created in the grease >>should drive the bearing out. >I actually tried this but it didn't work. >I ended up with grease everywhere and the bearing still in the end of the crank ;o( If the pilot bearing is an actual roller bearing, the grease trick won't work, it only works with a solid bushing. Don Graham ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Transfer Case 4-1 Gear Conversion I believe the kit is $1,300. The installation requires the modification of your front case half. The inside of the case is machined to accomodate the large 4:1 gearset. For this reason Mepco recommends you send them your xfer case and for about $200 they'll do the swap. So for approx. $1,500 you can have a bolt-in ready 4:1 xfer case. If you do the swap your self they will sell you an already machined case half and charge you a core charge for the return of your original front case half. They will then m#001#achine it and sell it to someone else. Here are my numbers (1st x diff x low range = crawl): Before: 6.34 x 4.56 x 2.72 = 78.63 After: 6.34 x 4.56 x 4.00 = 115.64 I haven't done the 4:1 swap yet. Some friends are bugging me to do it but I find 79:1 is plenty slow enough for me right now. At 116:1 the torque load on u-joints and other parts must be tremendous. Any thoughts on this? I think I'll invest in a good welder or heavy-duty rear-end first. For a stock vehicle this is the easiest way to go slow and keep your highway. I put in the NV4500 and that might not be an option for some people (cost wise). The 4:1 kit, ready to bolt in, at $1,500 is not that much when you consider how much it costs to swap gears (parts, labor, etc..) Stock: 3.34 x 4.10 x 4.00 = 54.77 vs 31.08 w/2.72 low range 3.34 x 3.54 x 4.00 = 47.29 vs 32.16 " " 3.34 x 3.07 x 4.00 = 41.01 vs 27.89 " " I can't remember what the stock tranny 1st gear was but the above numbers will give some idea of what the 4:1 kit will do for you. - Todd ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Brake Line Extensions >I see ads for brake line extension kits but I'm >wondering if there's a cheaper alternative? >I mean, couldn't I just buy OEM replacement >brake lines designed for a vehicle with longer >brake lines than my own? Aren't the fittings >some kind of standard size? Is it feasible >to buy generic hose and fittings and assemble them myself? IMHO Dont waste your money on braided stainless extended lines or anything similar. Simply relocate the stock brake line at the frame brackets either lower or further back on the frame to get them closer to the calipers. (I don't know where they are exactly on YJ's) Once the brackets are moved, run a short section of steel line from the old end coming thru the frame to the new location of the stock rubber hose to the caliper. A flaring set (double flare) may be req'd or use *Flare* unions, *not* compression fittings. This setup works great for me. I do carry a spare rubber line but have given it away more times than I've ever needed it (never). I have seen people get stuck with broken stainless lines that are often custom and expensive. Some have odd ends that cannot be easily swapped for stock lines. In the rear, move the brass tee to the top of the diff and remake two steel lines to each wheel cylinder. RICK BOIROS ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Shackle Reversal This reply is for Robert in Hawaii, and anyone else who was discussing flipping the shackles to the rear of the front springs on a Wrangler. Robert, your Compuserve address is invalid from my end - so I couldn't respond directly as it threw it back to me. Everyone keep in mind that these are my *personal* opinions on this subject and in no way should be considered 'official' just because I work at Jeep. Anyway, here's what I originally attempted to send to Robert: Unofficially, I would say that yes, the ride should improve with the shackles in back, but the things to keep in mind and consider before proceding are: 1) Since the frame is lower at the rear spring eye, you will be forced to lift the vehicle a fair amount - you may be happy with this side effect, as it will allow you to have a lift and retain the more desireable/efficient flat profile 2) The drop brackets you will need to mount the fixed end in front will put a *lot* of stress on the very frontmost part of the frame rails - laterally in particular. You will need to add a lot of structure and crossbracing to keep the stiffness of the chassis high enough to maintain the handling you have now *this is one area I've seen lacking in any 'kits' that are out there - they just don't do the engineering calcs to check for frame integrity! 3) You will be using your front prop. slip yoke more - this *shouldn't* be a big problem, unless you're running tons of lift and the prop is at a big angle to the ground - just realize you may wear it out and need a whole new drive shaft! 4) If you run big lift springs with lots of arc to them, realize that your tires now move up and *back* when you hit a bump/compress the suspension - which means your big meats will have more chance of hitting the fenders in the footwell area. Other than that, one more thing: If your Wrangler is still under warrantee - it's not anymore! -Jim Frens ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Removing the Steering Stabilizer > Sorry for this question, but I am having one > heck of a time with my steering stabalizer(sp?) > on my 91 wrangler. > I can NOT get the stock one off. I take the > cotter pin out, take the bolt off the top > and it won't budge. > On the back side, between the shock and the > drag link, there is a hex bolt, but I can't > get it to turn without flexing the hell out > of the link. So I'm not sure if the bolt > is thredded in or pressed in. > Does anyone know or have any experience > with this? > I even used a puller on it, but it only > punched a divet in the middle of the bolt. > > Scott N. He He He,,,,Sorry. I went thru this about a week after I got my 94 Wrangler. They LOCKTIGHT that frigging bolt in. I happen to have access to a 3/4 drive socket set. I also applied heat with a propane torch till I could barely touch the tie rod with bare hands. I ended up using a 4' cheater on a breaker bar to get it loose. - Dave Taylor Ya I know, it's kinda hard to get off. The link does flex but the nut eventually gives. Try spraying it with penetrating fluid. Once this is out you most likely will have to hammer the old stabalizer out. I hit mine at the point were it was attached to the link (sort of like a bolt sticking out of the underside of the link.) - Johnny Jeep Scott, I saw the suggestion about taking the entire link off with the stabilizer, and that may work. The bolt is a tapered pin that usually requires a puller. I tried a small 2 jaw puller on my '90 Wrangler and had no luck. I got a larger 3 jaw puller for mine, but haven't tried it because the cold weather pushed it down the priority list. If you don't have a replacement tapered bolt, then you could try to just remove the nut facing to the rear. I saw that you said that it was a head of a hex bolt, but I'm looking at a replacement Rancho bolt. Soaking it in rust loosener and angling the wrench so you pull parallel to the bar may help. If it comes loose, you just slip off the old stabilizer and put on a new one - that is if it's a nut rather than a bolt head. This might also be a good time to use a good poly bushing instead of the rubber bushing that might be on the replacement stabilizer. I've heard this tightens up the steering. - Mark Williams It'll be a lot easier to remove the whole assembly: Remove the nut at each spring mount. Remove the bolts holding the stabilizer bar to the frame. Flex the bar enough to remove each link from the spring mounts. Take it to a vise or a press, THEN you can remove that upper bolt. It is press-fit in. - Andy ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Airbox Intake Re-routing >Low point for water on the Wrangler is the air >intake, just below the right head light. If > you want to go deeper, disconnect the hose to the filter and put a dust mast over it. Tie it up pointing back. I removed the air intake which goes from the front of the air box to just below the driver's-side headlight. I then bought a short length of ABS pipe (I _think_ it was 2" dia) and 2 right-angle joints. The joint fits PERFECTLY into the hole in the front of the air box; no gluing was required. SIDE VIEW /--|-----| | j_|__p__| j = 90 degree joint === p = pipe front |p| +--------------+ of ===_| | jeep | j | air box | \--| | | | +--------------+ Parts cost was under $10 at any ol' hardware store. From this point, you could go even further and attach a snorkel to the pipe for the really deep stuff. (Thanks to Dave & Pam Hansen for this tip.) ...lars ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Automatic Transmission Adjustments BTW, to increase the rpm your Wrangler Automatic shifts at, there is an easy adjustment on the kick-down linkage under the hood. Just depress the half- moon metal holder and pull the linkage as far out as you want. The linkage will pull itself back in if pulled out too far. Anyway, it makes a hell of a difference when accelerating full-throttle, like I said, my Renegade used to chirp the tires going into second with the old 29" Goodyears. John Crowe ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Body Lifts Body lifts are the cheapest way of making room for larger tires. Advantages are: 1. Inexpensive. 2. Lower center of gravity than a suspension lift. 3. Provides room for greater articulation when larger tires are mounted and the axle is up against the bump stop. (This is why some Jeeps have modest 1" or 2" body lifts even though the suspension lift has provided plenty of room.) Disadvantages: 1. Doesn't increase the ground clearance. 2. Large body lifts (greater than 2 inches) may require that the body tub be re-inforced or else the metal around the body mounts may become fatiqued. 3. In most cases, the radiator shroud or radiator must be lowered, even for modest 1" lifts. Larger lifts may require other changes to transmission/transfer case linkages, wiring, and the fuel filler. Some opinions on the topic: Just a note on inexpensive but effective body lifts. In helping a fellow Brush Buster in a ground-up restoration, we used boat trailer rollers. They are 2 1/2" in diameter and already have a 1/2" hole on the center. We cut them to size with a chop saw. We saw prices from 7$ to around 12$ each. They were about a foot long and very hard. They are cool because they are larger than standard body mounts and have more area to support the weight of the body. Al (too much to do before rubicon) Temple 69 CJ-5 69 WAGONEER 93 TANDEM 14' TRAILER (HI MIKE J.) BRUSH BUSTERS ALOHA OREGON re: Hockey Puck Lifts A single Hockey Puck should be fine, it is when people start stacking them that trouble occurs. Stay away from the marine stuff, its too soft. Might want to replace stock body mounts with Urathane, this will add another 1/8" as it doesn't compress as much as the rubber ones do. Christopher Siano re: Hockey Puck Lifts I don't know about long-term hockey pucks, but I've had mine on for about 1 year with no signs of adverse wear or cracking. I've also heard that the nylon or other type of hard plastic work well too. If you have access to some for free...what the heck! The commercial body lifts are made from something like extra-hard-poly-nylon-vinyl- type-stuff anyway, so the nylon boat rollers are probably not too far off from the right thing In short, Give It A Try! By the time you have had something on there long enough for it to give out or fail, you will probably be ready to change it anyway!! Chris Eicher A guy on the offroad list who lives up in Oregon uses the boat rollers. He cuts them to the desired thickness with either a bandsaw or a sawzall. They already have the holes drilled in the center. If a roller is 18" long and your saw leaves a 1/8"(3mm) kerf then you should be able to get 16 "pucks" from an 18" roller. If the roller costs you less than $16U.S. and hockey pucks cost at least a dollar, then it's cheaper to use the rollers. Either cut the rollers or drill the hockey pucks, you still have labor involved. Here in northern Calif, it would probably be easier for me to find boat rollers than it would be to find hockey pucks. mike. You reach a point with a suspension lift when you've gone high enough. The attraction (to me) to do a 1 inch body lift is that you are lifting the body only - you dont put the engine up higher or anything else that is bolted to the frame - this (in my sick logic) means that your are getting the additional tire clearance with the *least* amount of center of gravity lift that you can do (without cutting the fenders). Graham Knight And now, here's how to do a cheap-o 1" body lift on your Wrangler/YJ by using hockey pucks: To do the puck lift, you'll need to buy 11 hockey pucks, preferably made in Canada rather than some economically distraught eastern European country. These pucks will be placed above the existing body mount bushings at the following locations: TOP VIEW +------------------------+ <-- front bumper +------------------------+ ||bbbbbxbbbbbb|| ||--radiator--|| || || || || x = body mount || || b = indicates the || || front brake line ||x x|| (approximate) || || || || || || ||x x|| || || || || || || ||x x|| || || || || || x x || ||+----------+|| ||| ||| ||| gas tank ||| ||+----------+|| +--x--------x--+ +--------------+ <-- rear frame end-cap You'll need to buy some Grade 8 bolts as well: Original Size New Size 6 x 4-1/2"x1/2" 6 x 4-3/4"x1/2" 5 x 3-1/2"x7/16" 5 x 3-5/8"x7/16" (Thanks to Stephen A. Church and "Beans" for these measurements.) The procedure is as follows: 1. Loosen all bolts and remove the ones from one side and the one in front of the radiator. 2. With the removed bolts, use them to figure out what size Grade 8 bolts you should buy (hint: they should be 1" longer). (BTW, the stock bolts are Grade 5 so you may elect to use that grade...I just have a fetish for Grade 8's.) 2a. While you're at it, remove the bolts from the thin metal bracket which runs horizontally in front of the grill, between the frame rails. This bracket is used to route the brake line from one side of the vehicle to the other. It will have to be raised or otherwise modified. 3. Drive to the closest source of quality bolts (they're probably closed, though). 4. If they're open, buy the bolts you need, including the longer ones for the brake line bracket, too. 5. Drill holes in all of the pucks. Try to keep them centered. 6. Use one or two jacks to raise one side of the body. 7. Insert the pucks above the rubber body mounts, against the bottom of the body. 8. Insert and thread the new bolts into the holes. Leave them loose. 8a. Remove those bolts because you forgot to dab them with Loctite Blue. Repeat step 8. 9. Do steps 6-8a on the other side of the body. 10. Tighten them to the point where the pucks deform. It's possible to crush them so don't go crazy with the wrench. (Some people recommend tightening until the rubber bushings bulge out; YMMV) 11. Depending on your vehicle some of the pucks may have required trimming to fit snug against the body. With the leftovers, you may have a couple of pieces large enough to use as spacers for the front brake line bracket. Lift them 1" higher with these spacers and bolt down with the new bolts. 12. By this time, you might have noticed that your fan is rubbing against the fan shroud. Doh! To rectify this problem you can drill new mounting holes to either lower the shroud or lower the radiator. In any event, it's much easier to work with the radiator removed from the vehicle. I didn't do this but had the advantage of using a right-angle drill. 13. You're done! ...lars ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Full Roll Cage > Has anyone done a full cage for Wranglers (YJ's) >that have the windshield side braces? Kits in >catalogs are for CJ's, never seen kits for YJ's. >Basically, putting windshield down on these YJ's >is a pain, and a full cage is nice for mounting >electronic gear. If done right, they add safety. Check the home page for Esprit de Four 4x4 club based out of san Jose. The URL is http://www.weber.taligent.com:8088/esprit/ There are several photos of a full cage custom built for one of the members YJ. The cage does not retain the windshield support, but there is no reason you cant add them onto a cage. I am in the process of building a front cage for my YJ and have discovered that the cages built for late model CJ's will work in the YJ's as well. You can use either the cage designed for a padded dash, which will allow esay access to the bolts to lay down the windshield, or you can get the cage made for a non-padded dash (I got this one) and change the windshield release bolts from Torx head to standard bolts. - Ed Cox ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Installing Rear Disc Brakes Group, I'm still alive here in Oregon, Just busy.... I wanted to share this with anyone considering this modification. Company: Stainless steel brakes corp. Kit: Wrangler rear disk brake conversion. 4 hour install no drilling or welding. Cost: $500.00 smackers Vehicle: 1993 Jeep wrangler, I-6, Hardtop, Dana 35-c axle When opening the box I was very impressed with all the components, Quality stuff. The instructions looked great and they even came with a beautiful blueprint. However, I did find ALOT of problems when installing. Some of you may think I am to critical, but for 500 bucks and and a kit that says 4 hour bolt on with no drilling or welding I don't feel bad about bringing up the issue's I found. These issues were simple for me to deal with because of the tools I have and the resources I have around me. Some of you may or may not have these resources which could turn this into a real problem. I started by pulling the axles whose diameter impressed me. I found the first error in there claiming the pinion retaining bolt was a 5/16 when it really was a 1/4 twelve point. Do you have a 1/4 twelve point wrench?? I did but could not find it, so there's one trip to the store....I had removed all the original drum brakes and was now in process of bolting up the disk hardware. Next bummer was that on the caliper mounting bracket one of the bolt holes was just a hair off from lining up properly. 10 strokes with a rat tail file and it went on fine. After that I found that they gave me coarse threaded nylock nuts for fine threaded bolts. Thats another trip to the store.... I went to put the new rotor on the end of the axle and the centering bore in the rotor was way to small. I drove to a fairly local machine shop and had them remove .010 thousandths out of the center bore. Not enough, I grab the stock drum and the rotors and bring them back to the machinist who can now remove the correct amount from the center bore of the rotor using the stock drum as a template as my micrometers are to small to measure something that big. The rotors now slide on fine but now rubs on the caliper mounting bracket casting that supports the dust shield. A little clearance grinding with my die grinder and everything clears OK. Everything else went pretty good until I find that the emergency brake cable bore on the caliper is to small for retaining the E-brake cable. _IF_ the E-brake did fit, the cable still would be to long for proper actuation. I have not finished this part of the install and the solution will be to install a sleeve or bushing to retain the cable housing which installs in the caliper E-brake bore and gives the proper distance for the E-brake cable to fit in the caliper actuating lever. Get that? The only thing I feel is mandatory for this kit (that is not) is the hard mounts with retaining clips for the rubber brake lines where they meet the steel brake lines on the axle tube. I have fabricated these and will weld them on when the Jeep comes back over to play... My overall impression is that they need to get a Wrangler and install one of their kits and iron out some of these wrinkles. Once done and you stand back and look, the rear disks are beautiful! It is simply put, NOT a 4 hour bolt on kit....... I did call them and they were very nice, but they could do nothing for me as I had already taken care of all the issues I discovered. I personally can build a rear disk setup using all GM stuff for around 300.00 to 350.00 but it is far simpler sometimes to buy a complete kit. As always......YMMV. Al Temple ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Spare Tire Carriers The addition of a larger spare tire can weaken and damage the tail-gate. For this reason, after-market manufacturers have seen fit to produce _expensive_ but strong tire carriers which either mount to the Wrangler's body or attach to the bumper. Now, I've been offroading with a 31" spare on the back of my YJ for over a year now and have yet to notice any adverse effects. Even so, I _will_ be making a stronger tire carrier some time this year. But even if you decide to stick with the tail-gate-mounted tire carrier, be forewarned that unless you use a wheel with less offset than the factory wheels, you will have to lengthen the mounting studs. This can be accomplished by removing the carrier from the tailgate, heating the studs with a torch, and then hammering them out. Once you've got 'em out, you can replace them with some longer bolts and tack weld them in place. If you have a hard-top, you'll still have problems. The added height (diameter) of the spare tire will interfere will the rear lift gate whenever you try to open or close it. There are three solutions to this: Expensive Buy a new spare tire carrier. Time-consuming Build your own custom carrier or have one fabricated (in which case it goes back to the "Expensive" category). Cheap Buy an adapter which provides longer studs and offsets the tire a few more inches to the rear, thus providing just enough room to clear the lift gate. For those of you who are interested in building your own tire carrier or having one fabricated, here's some ideas which have been tossed around: Subject: Seeking critiques for my cunning tire rack plan There's been a recent thread about building a spare tire carrier which mounts on two or more hinges to the bumper/frame and pivots up and down instead of sideways. Well, I'd also like to mount a tire carrier which puts all the weight on the bumper/frame but don't like the vertical swing idea. How about something like this (application is for a Wrangler): Rear View _ | | -------------------------H| <-- vertical post / -----|-----|-----------H| / / | S | | | H = hinge / / | | | | L = latch / -------|-----|-----------H| S = spare tire mount / /-------------------------H| /L/ /| |\ <-- bracing ------------------------------------- | | ------------------------------------- --- Replies ------------------------------------------ I just got off the phone with a fellow who is going to build such a bumper for me. The company is called Off Road Spare and they build these square tube bumpers with swing-away tire carriers for many types of vehicles. I'm not capable of fabricating (I like that word also) such a bumper, and that's why I'm having it built for me. What I found out is that there will be an article on this design in the next issue of 4WD&SU, so you might want to hold off building this creation of yours until you read the article. You might get some good ideas as to what may/may not work, or just some fresh ideas from someone who builds these things for a living. From the pictures of the ORS bumper that I've seen, and from a similar bumper made by Rickard in Southern California that I've personally seen in action, your design appears to be a little too complicated - you seem to be over-building this thing, especially in the area where it mounts to the bumper and pivots. I don't believe you need the vertical post that blocks the passenger side tail light. Shel Belinkoff ====================================================== Larry, there's a MUCH simpler (well in terms of number of welds, amount of tubing and problems to worry about) way to make your tire carrier. Kayline makes one for 80 series LC's that's quite a funky design. Here's a poor attempt at an ascii rendering of it. ____ | o | <------ Tire mounts here (some kind |o o| of spacer should be welded on) | | | |__________________ | Say, 2x1" square tubing| |_______________________ | ___________________________|__| <---1" Round post | Big-ass tube (round is better for tanks) |\/| |________________________________________________|/\| I'm not quite sure how the rack attaches to the bumper but I've read they use Timken Roller Bearings so I imagine it'd look something like this |POST | /| |\ <--poor representation of filler metal =========== <-flange welded on post \_________/ <-roller bearing | | | | | | | | | | _|_____|_ brazed / \ <-roller bearing spacers... =========== <-thrust washer |__|___|__| <-big-ass nut |-----| |-----|<----threads cut on post ----- ____________________ |\ /| |_\ /_| <-Inner races | Tube at | (held in by | 90 to the | heat shrink- Bumper | bumper | ing or set |_ tube _| screws or | / \ | little _______|/__________\| on You could tap a zerk fitting onto the bumper then just pump the chamber (that the upright pipe bolts through-not the main one!full of grease, packing the bearings! Your tire carrier would always be SMOOTH (unlike you with some fire water in ya :) would never sag (unlike you with some... Mayber I better stop this here) BTW, another trick I heard about is mounting a spare spindle to the carrier, putting a complete hub on that and then attaching the tire to the studs on the hub! That way, if you ever toast a spindle/hub/wheel bearing, you've got a redi-made replacement assembly. Food for thought. On my Cruiser, I could even use wheel-bearings for the pivot point of the carrier! YEAH! Then I'd have EVEN MORE spares (Like I'm ever going to manage to toast any part of the axles anyways ;) Rob Mullen Larry - this looks a lot like what I'm planning for my CJ, except I'll run 2 vertical posts & attach the factory swing-away carrier & latch to them. >2. If the rear bumper receives a major impact, >the vertical post may get driven into the body. >Yeah, well - ever seen a rear-impact wrangler with >bumperettes? The tire totals the whole gate area. >My questions: > >1. Anyone have any opinions on this? Yep - here! >2. Does this seem structurally sound? Yes, except for one possibility: if you mount a big tire & gas can(s), you got a lot of weight up on top of this post. (I'm adding a Jamboree rack too - should total 250+ lbs loaded w/ tire & 2 cans). There are 2 issues with this, IMO: 1. The factory rear frame x-member this whole shebang bolts to is a joke. Maybe you want to replace it w/ a beefier one? (I'm using 3/16" C-channel) 2. Support issues are handled, but what about vibration? A washboard road with some pitching should be able to destroy even good welds with enough vibration. I plan to tie mine to the factory body mounts for vibration support only. To allow for frame-to-body movement, I plan to try 2 studs with a rubber thingy in the middle: ----- ====| |==== ----- (MSD & Jacobs sell small ones for vibration-mounting their ign stuff) >3. Would it continue to be structurally >sound if I also mounted > a spare gas can onto the swing-away >frame as well? See above. Jeff Layton > | | > ---------------- | <-- vertical post > / --|-----|------ | > / / | S | | | Weld entire assembly > / / | | | | L = latch > / ----|-----|------ | S = spare tire mount > / /------------------ | > /L/ | | <-add a flange here > ------------------------|-|--- > | | | | > ------------------------|-|--- --- This is a great idea, but you might be making it too complicated. My suggestion would be to make the vertical post out of thick wall tubing or even a solid round bar. mount a piece of tubing vertically through the bumper and let the whole mount pivot through that. Put a cotter pin in the bottom and a padlock on the latch end and it is very secure as well as simple. If you want to put a lot of weight on it , put another post on the other end and have the crossbars go all the way over. The main weakness of latching it on the bottom is that it will the weight is outside the "triangle" formed by the attachment points and it is going to bounce some. Ask anybody that put big tires on early 'cruiser tire carriers. Brian Millin ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Spring-Over Conversion - Experiences & Opinions M.I.T. of El Cajon (of xfer case conversion fame) does Wrangler springover conversions. I had this done recently, and am quite pleased with it. They use the stock springs with one added full-length leaf. The ride is not quite as good as stock, but close. Approx. 5.5" of lift results. The also redo the shock mounts to allow MUCH longer shocks for more droop. A dropped pitman and an offset tie rod (or is it drag link? -the thingie attached to the pitman) are included. The standard track bar mount on the D30 disconnect housing is cut off (I think for tie rod clearance) and a new mount is fabricated on the spring u-bolt plate, now on top of the axle. The rear track bar is removed. The sway bar link is shortened. Also, it looks like poly bushings were put in the spring ends. Jeff at M.I.T. recommends 33 or 35 x12.5 tires on 8" rims with 4" offset. 33s are pretty safe with the stock D30. I changed the rear to a D44. Until I pay off my credit card, I'm running 31" M/Ts, so I have plenty of fender clearance!!! I asked Jeff about axle wrap, and he said it has never been a problem. No kicker shocks or similar devices are used. Incidently, Jeff also does not believe in shackle reversal with a flat spring. I experience zero bump steer, even off road. (I'm running stock offset wheels, though) I don't know what the max articulation is, because I haven't lifted a wheel yet (I tried). I also had the xfer case conversion done, and a cv driveshaft installed. The xfer case was not lowered. I have experienced no driveline vibration. Cost is around $1500 installed, not including driveline work. As mentioned previously in this list, they are nice people down there. - Dion Davis And now for the contrary views: None of the Currie Wranglers / CJ's are sprung over. These are the gurus. Read the magazines. Most of the Cal. rigs are axle over. Is it really worth it?? I would only do a spring over if I was looking for 36"+ tires. - Rick Boiros I've spoken with someone who works at a local Jeeps-only shop. They've done a few spring-over conversions on customers' vehicles and their own. Their experience has suggested that a spring-over would be great for offroad-only vehicles. Unfortunately, they also found that the highway manners of the modified Jeeps was too squirrely. Some of the owners had the modifications reversed. - lars ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Torque Converters - Offroad Considerations Date: Thu, 10 Aug 95 10:47 PDT From: gpritcha@vanieee.wimsey.bc.ca (Gordon Pritchard) To: Offroad@ai.gtri.gatech.edu Subject: RE[2]: Lower Stall Speed? On Wed, 9 Aug 1995 Shel Belinkoff <belinkof@netcom.com> wrote: >I was about to call my tranny rebuilder to make an >appointment to have my Scout's Torqueflite done over, >but realized that I wanted one more bit of info >and some more opinions on the subject of the >stall speed. >It's my understanding that for offroad use a lower >stall speed is the way to go. How does a lower >stall speed affect performance on the street? >Is acceleration reduced? I'll share my mental picture of what the torque convertor is like, and specifically my thoughts on the offroading of same: I mentally picture two fans facing each other. One is driven by your engine (under power) the other pinwheels in the breeze of the first (input to your tranny). In my mind, stall speed is the maximum difference in speed you can get between these two fans. At this max. diff point, there will exists a torque multiplication caused by high airflow over the second fan. Blade pitch and amount of flow affect the amount of multiplication (among other things). Instead of air, substitute "tranny fluid" above, and then you'll have the picture. Things are different when you get up to speed, but that's another story... So, for uphill climbing, I figure you'd want max torque multiplication (much like everyone wants a low low range). For this, you'd want a high-stall torque convertor, popular among the muscle car crowd. However, for engine braking downhill, you'd want a low stall speed torque convertor, to maximize the fan coupling described above, and give you some braking. The only thing I know of to give you this is the older Switch-Pitch torque convertors. I have only heard of them for Chevy Turbo 400 trannies, but they may exist for others (in this design, a dash toggle switch changes the internal blade pitch, to give you both high torque conversion, or tight coupling for good fuel economy). If your gear ratios are what you like, I'd suggest a tight (ie low stall speed) convertor to give you tighter throttle response and enhanced engine braking. OTOH, if you are struggling up hills, and this is important to you, go for the higher stall speed. Be aware, though, of using a high-stall convertor continously at wide throttle openings - they can balloon/burst due to the extreme internal fluid pressures generated! FWIW, Gordon Pritchard, VE7AGW ------------------------------ I think this is a good view of how a torque converter works, Gordon! I might add a couple of comments. First off, you can get lower than stock torque converters. However, they are rare and usually these are called towing converters. I was thinking about going for one of these, but in the end, decided I didn't want a tow truck, I wanted an off-road truck. Most people agree that a few hundred RPM above stock is what I wanted. I asked a lot of people. The racing crowd loves those 1,000 RPM over stock. By the way, the definition of stock is completely unknown. Chevy couldn't tell me, B&M couldn't tell, the tranny rebuilder couldn't. Everyone had a different answer. For my TH-350, around 1300-1500 RPM was stock. The B&M Saturday Night Special Off-Road Version I got was about 1800 RPM. Second comment is you can spend from $60 to $300 for a converter. Few companies have RV or off-road converters, and those that did, it was a $300 special order item. I wasn't willing to spend that much, but did spring for mine mentioned above at about $150 (I don't recall exact price). Third, you need to match your converter to your engine. If you have a built engine that is built for a purpose, you need to get a converter to match. All the companies will ask you about your engine and the use of your vehicle when buying a converter. Finally, the bigger the converter the better. For example, I could get 9", 10", 11" or even 12" converters for my tranny. I opted for an 11" just because it had the features I wanted (stall, brazed internal fins, one piece construction, needle bearings, guarantee, etc.). These are things you will want to look for. Talk to some of the converter companies and ask why their top-of-the-line converters are better. I am happy with my set-up. The combination of converter, heavy duty tranny rebuild and rebuilt drive-lines showed definite improvement in my rigs off-road ability. Just another data point and opinion... - --- Rick D. Anderson (intsys!ricka@ormail.intel.com) Interactive Systems, Inc. 503-627-0149 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Automatic Transmission Fluid - What Kind to Use From the Chrysler FAQ Question: Can the so-called "universal" automatic transmission fluids be used in all Chrysler Corporation vehicles calling for ATF+? The labels of the universal brands do not mention Chrysler applications. Answer: There's a good reason why universal brands do not mention Chrysler applications. Chrysler now recommends that only ATF+ Type 7176 (PN 4467721) be used in all Chrysler automatic transmissions with locking torque converters. Substituting any other automatic transmission fluid can lead to drivability problems. Mopar ATF+ allows more slippage than other friction-modified fluides. Introduced on select 1989 models, the A-604 was the first transaxle to feature fully adaptive electronic control. As constant development of the technology continued, it spread to other Chrysler automatic transmissions including the 41TE and 42LE. As a result, shifting and engagement of the torque converter cluch (TCC) in virtually all Chrysler automatics is controlled by the transmission control module (TCM) based on a variety of inputs including throttle position, engine speed, input and output speed and others. The result of this adaptive straegy is that the TCM "learns" specific operating characteristics and conditions for an individual transaxle. To accomplish this, the lock-up torque converter must operate in three states instead of just two: unlocked, partially locked and fully locked. In partial lock, a regulated amount of slippage is allowed at the converter cluch. If the wrong automatic transmission fluid is used, the TCM can't effectively regulate the amount of slippage in a partial lock condition with the result being converter cluch shudder. Therefore, it is important to use only Mopar ATF+ in all Chrysler automatics to avoid driveability problems. -- Wayne Toy milnet: toy@dockmaster.ncsc.mil ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ How to Deal With Chrysler Corp. From the Chrysler FAQ * Be *polite* and *calm* but assertive at all times. Do not take no for an answer but do *not* act angry or threaten them. This will only make matters worse. Chrysler's customer service is often very good but the people seem to be very sensitive, for some reason. They also often don't know what they're talking about, so elaboration may help. If all else fails, thank the person, then immediately call back and speak to someone else. Always take down their name for your reference! * Know what you're talking about. Check the FAQ, TSBs, and recalls (using the free Alldata "titles- only" service and posts in the newsgroup) before you visit the dealer with a problem. Using the Alldata service may lead you to have new, lower standards for fair treatment. * Don't expect Chrysler to change something just because it's listed in a TSB (technical service bulletin). TSBs describe solutions to problems which may not apply to your car; they are *not* recalls, though Chrysler often fixes cars out of warranty if there is a known problem and TSB on it. * Even if you are in an adversarial relationship with a dealer or Chrysler, always act in a friendly, nonthreatening, non-angry, non-adversarial manner. You can get more flies with honey than with anger. Or something like that. * Don't take "no" for an answer from a dealer. Immediately call Chrysler at 800-992-1997 from a pay phone if you have to. They will call the dealer. Often, work the dealer would charge hundreds of dollars for will suddenly become free. Jobs the dealer wants to have your car for over a period of days will suddenly be done within the hour. Loaner cars will miraculously become available for free. * If your dealer keeps fixing the same thing over and over again, get another dealer. * If your dealer treats you badly, lies to you, refuses to do the work, etc., get another dealer. * Look for five-star dealers, but remember that five stars is not an assurance of high quality, and that great dealers may get less than five stars. Statistical sampling is not a high art at Chrysler Corp.; their survey form desparately needs work from people who actually understand how to survey customers. * If you have a continuing problem, speak to the people at your zone office (in your owner's manual). Be polite but assertive. They will probably send down a factory rep. Do not threaten them. If they still don't fix the car, politely begin to negotiate. * If that doesn't work, take the next step and contact Chrysler in Highland Park (800-992-1997). * If that fails, there are two steps you can take. 1. File an official lemon law complaint with your state. Do not assume that your negotiations with Chrysler should suddenly come to an end or become angry. This will get their attention, but chances are your problem is not serious enough to merit a legally imposed solution. 2. Go through the Customer Arbitration Board. * Most problems will end there. If not, look through your Yellow Pages to find a lawyer *specializing* in lemon law problems. Most lawyers don't know the first thing about lemon law! A good specialist lawyer will immediately know the people at the zone office and will first try to talk nice to them to solve the problem. If negotiation is not their first move, they are not the right lawyer. Normally, you can get a better deal through negotiation than through lawsuits. (This may not be true for all states, but it sure is in New Jersey). * Realize that your chances of getting cash are EXTREMELY slim. You will probably get a replacement Chrysler product. This is OK. You will not get all of your money back, either as credit towards a new car or as cash, no matter what you do. Chrysler's policy on lemons is to follow the state law, though they will negotiate. Most states impose a penalty on each mile of use before the first lemon-type complaint. This is normal. * Go through the latest TSBs again. *Whenever your dealer lies to you or is too incompetent, send a letter to Dealer Agreements or the Customer Center, Box 302, Centerline, MI 48015. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Ring and Pinions The gear ranges for carriers for the model 30 and 35 are: model 30 high - 2.7 to 3.55 low - 3.73 to 4.56 model 35 high - 2.7 to 3.31 low - 3.55 to 4.56 If you currently have 3.55 gears, you should only need a new front carrier. You can buy a new open carrier from 4 Wheel Hardware for about $70 US (probably about $500 Canadian :) ). The only extra labor should be to swap the spider gears from the old carrier to the new one, because it all has to be taken apart and setup for the new gears anyway. Don Graham ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Should I Install a Locker in the Front or the Back? For purely offroad use, I would always go for one in the rear first because: a) You generally need a locker the most when you're going uphill and when you go uphill, the weight transfer goes to the back. b) Wranglers don't have particularly strong front axles, especially when you throw in large tires and a lockers. Climbing over rocks with the front-end locked-up is more likely to break something than an equivalent setup/situation in the rear. Having said that, I'd be very wary about installing an automatic locker in the rear if you spend a significant portion of your winter season driving on hard-packed snow or ice. In that situation, I'd go for an ARB or a good Limited Slip in the rear. Another alternative is to use a Lockright in the rear which can be removed/installed in an hour without any special tools. Although you'll have to remove/install it twice a year, it's less than half the price of an ARB. You might find this interesting: I don't like limited slip diffs except in light trucks such as my former Suzuki Fox (Similar to Samurai but with a long body) it did wonders in the rear axle. But that is the only time I have seen them doing much good. Here in Iceland the preferred locker seems to be ARB. Every serious Off-roader has one (except me and other Toyota Double Cab owners. OK some of them have ARB in the front). At present I have no locker up front but I have a standard (here at least, not in the US) electronic 100% locker in the rear. It works similar to ARB except instead of air actuated it has a electric motor on the diff housing which does the work. As to Stevens Perkio note about snow and lockers: Yes lockers are a pain in snow UNLESS you can unlock them. I can't understand what people have against ARB lockers here on this list. To me they seems to be ideal, you can lock them when you nead them and unlock them when they are not needed. 2 years ago I did a test. I hooked a timer to 4 off roaders with ARB on both axles. On timer for each axle. All of the trucks were used as a everyday cars besides off roading. After over a year I took the readings. (1 year approx 8760 h) front axles locked Rear axle locked 1 38 h 35 m 68 h 5 m 2 5 h 48 m 830 h 5 m 3 4 h 32 m 633 h 38 m 4 2 h 43 m 521 h 36 m Unfortunately I don't have the time driven or distance driven in that time available right now (got it somewhere on backup...but where?). Car one was sold shortly after I installed the timer and the new ovner had little experience in off roading. (And he broke one front axle in those 38 hours he had the front diff locked. After going with him twice I noted that he had the habit that if he saw a steep hill which we where going over he locked both front and rear diffs and flored the gas petal... and usually he flew over the top. It was in one such landing that the truck landed on one front wheel and broke the axle) This is to strengten by belive that diff lock in the front axle is rarely needed. (but if you need it you sure need it :-) ). Unfortunately I didn't install a timer in my truck when I bought it. It would be interesting to have now the readings. So why drive all the year round with locked/semi locked diffs if you really need them for fraction of the time? In steps ARB (or Toyota standard electronic locker :-) ) Just IMHO. Gustav K Gustavsson ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Transmission Gear Ratios Two transmissions were used in '87 Wranglers with the following ratios: 3) Transmission: Peugeot BA 10/5 Axian AX5 --------------- --------- 1st = 3.39 3.83 2nd = 2.33 2.33 3rd = 1.44 1.44 4th = 1.00 1.00 5th = 0.79 0.79 Rev = ?? ?? Terry ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ What the Heck is a Banana-Rating [tm] ?? Having started this whole Shade Tree Howler Monkey [tm] reference, I feel obliged to reveal the rating system for a job's degree of difficulty in STHM terms: 1 banana = easy 2 bananas = moderately difficult 3 bananas = pushing the limits of a stock howler monkey; opposable thumbs only get you so far 4 bananas = requires the ability to communicate abstract ideas to other howler monkeys. 5 bananas = the job should only be attempted by a professional orangutan Hope this clarifies things. ...lars ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ What Tires Fit Under What Lift? Rule of thumb FOR OFFROADING ONLY: 31" 2" lift 32" 2" lift 33" 3" lift 35" 4" lift with a small body lift For street-only, you can get away with a bigger tire under a smaller lift because you won't be working the suspension in its boundary states (full extension/full compression). ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Adjusting the Steering Stops -- Tires Rub Against Springs > I'd like to adjust my turning radius so that I >prevent the 31" tires from rubbing the >springs. Does anyone have suggestions on how to go about Turn the wheels to one lock. Look at the other wheel, inside. You'll find a bolt which, when turned to the lock, contacts part of the axle assembly, stopping any further movement. This bolt has a nut welded on it to provide the factory turning radius. You can back this bolt out, put a washer (or 2 - test first) behind it, apply some locktite, and reinstall. This will give you a larger turning radius, but will save the edges of your tread from rubbing on the springs. Andrew M. Formella ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Axle Upgrade Options The Bolt in 44 swap that I know of does require a transfer case change. BUT the Dana 300 Jeep has the same bolt patterns as the NP231, 241! So you get rid of the stupid slip joint setup too that people are spending too much money converting. While your at it, swap in a good transmission and CJ7 stock length driveshafts to match. Now for the all important information.....Get out the tape measures. The SCOUT II Dana 44 has the same spring perch locations as the Wrangler Frame. Overall length will be slightly wider, but can be made up in properly offset wheels. Use the rearend from the same donor vehicle for the matching rear Dana 44. Spring perches will have to be ground off and welded closer in. There's probably more to this, but those are the basics. Any suggestions or FIRST HAND info is welcome before I start building Wranglers with GOOD axles and selling them. - Rick Boiros Later, Rick added: >From Larry Soo: What kind of things would be required for this swap? Of the top of my head, I can see that it'd need to be: - - narrowed >>> Not necessarily...get out the tape >>>measures. - - new spring pads >>>>SEE ABOVE - - new shock mounts >>> Yes, good chance to move from ground >>>level. - - either use an AMC rear axle as well or else change the front wheels to use the Chrysler Jeep wheel bolt pattern (what's involved in this procedure??) >>>This is a good one since jeep trucks were 6 lug. swap CJ or Scout knuckles,spindles, rotors and brakes for 5 on 5-1/2 b.c. up front. Use a Scout or '86 CJ wide 44 rear. ?????? open for discussion on matching fronts and rears. i originally suggested a matched set of scout 44's. ^^^^^ - - maybe a larger master brake cylinder >>>Doubt it, 77 and 78 CJ's came with these same large brake calipers. - - are any steering linkage changes required? >>> For uncut width, use stock linkage from donor vehicle. Possibly modify a drag link to mate to the Jeep. - Rick Boiros If you want to upgrade to beefier axles while retaining the 231 xfer case, try to get axles from a classic Bronco. The axles are approximately the same width as stock and the front diff is offset to the driver's side, just like the YJ's original Dana 30. Dana 44 front axles are good - when were they offered?. * 66-70 FORD used Dana 30 frontend, they are junk... 71-77 they used the Dana 44... Dana 44 is the way to go... Were front discs available and when? * Front disk brakes were added as nonpower assist in '75, and power assist in '76.... Preferred rear axle? (was there more than one type available from the fact.?) * FORD 9" axle was used from 66-77, but there were differences in strength depending on which capacity axle was ordered... The stronger rated axles (larger bearings and axle shafts) used 11" drums and beefier parts.... The standard GVWR axles used 10" drums with small diameter shafts and bearings... '74 model year rear axles had oddball axle and bearing combo's that are hard to replace... '76 and '77 models used triangulated housing axles that provided radical improvements in strength of the housings as well as the axle shafts and bearings... The heavyier '76 and '77 9"ers are just about bulletproof in these trucks... - SMD ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Front Shackle Hanger Problem Another weak Jeep spot (while I'm on the subject) is the front shackle hanger on the Wranglers. This hanger (unlike the CJ) is welded to the frame and can not be replaced. The stress point is the thin section of bracket between the bushing sleeve and the frame. At some points, this metal is only 1/4" thick! And to top off the trouble, the bushing sleeve isn't welded to the brackets at this point!!! I managed to shear off this mount on the driver's side and had a couple of friends reweld it for me. This same corner was hit in my accident, and the mount held, so their reinforcement work did the job. Basically, the hanger was reinforced by fitting a piece of 1/4" plate into the gap between the brackets holding the bushing sleve. The piece was welded to the bracket, frame and bushing sleve eliminating the open space. Careful grinding and filling made the fit tight and professional. Never again had a failure. In fact, the leaf spring broke in the accident, but the mount held perfectly. Chris Siano ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ GM Alternators in a Jeep I put a 110 Amp GM alternator in my CJ7 with no real modifications. I have an AMC V-8 with the york compressor on it so space is more limitted than the I6. The H.O. Alt. is only about 1/2" deeper and maybe 1/4 - 1/2" larger diameter. I also added a 10 GA wire from the charging terminal to the + side of battery with all other cables 00 GA. This set up works great even with a single battery and Warn 8274 winch. Now if I could weld with it..... Rick Boiros ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Jeep 4.0 EFI engine stalls at a stop (Jeep 4.0 stalling). From the Chrysler FAQ The problem is the flywheel sensor. This sensor tells the computer the RPM, duration, etc. It is located by following the wires from the along the firewall and along the bellhousing. These sensors get worn out from debris and it also might be just the wires going to it. I had the same problem and took it to a dealer and they couldn't figure it out either. (Ken Talley) ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Loctite vs. Anti-Seize Compound Just finished goofing off and reading the O-list digests. Saw your posting, and felt I could clarify Locktite versus antisieze: Locktite: Tradename for a whole host of adhesive products. Around automotive stuff, most common are Locktite 242 (blue) and 262 (red). They are both anaerobic adhesives (meaning they cure _only_ in the absence of air), intended to fill small gaps only, such as might exist between a nut and bolt when tight. They both are applied before joining the fasteners (Locktite make some that you put on _after_ joining and tightening nut and bolt). The red stuff is classed as permanent, requiring a torch to remove later - not recommended. The blue stuff is classed as "small hand tool" removeable, and is the most common. 3M and others (LePage?) make "Locktite Blue" clone products, which are much cheaper. Around electronics we use Locktite Purple (really lightweight, breaks free pretty easily, sometimes we'll use nailpolish instead - gives you an idea that it kinda only holds things in place lightly). We also use some Locktite screenprint epoxies to hold surface-mount electronic components on circuit boards during soldering. Locktite will inhibit corrosion within the joint pretty well, by simply occupying the tiny voids and excluding air (in my experience, anyway). Undoing a Locktited joint will yield a crumbly powder (normal) which must be wire-brushed before reassembly (or new Locktite will be compromised). In summary: Locktite Blue is a retention scheme, with slight corrosion resisting side effect. Antiseize: Basically greases with metallic content. I forget all the various metals which the different manufacturers use, but copper is one, and I've got some silvery stuff on the go at home. Because this is a grease, it _will_ affect torquing of bolts - wet (or "lubed") torque is significantly lighter than dry torque for the same fastening power. I have a chart somewhere which call out equivalents when lubed with engine oil. It's really easy to overtorque a wet bolt, causing thread sripping or bolt elongation and failure. Antiseizes work on two levels: By excluding air from the bolt-nut interface, and the metallic compound used can reduce likelihood of electropotential corrosion (caused by dissimilar metals in contact, along with moisture, and ions present in moisture). Primary protection is really by air exclusion, though. Antiseizes should be used with some additional mechanical retention scheme such as lockwashers, Nylock locking nuts, safety wire, etc. If you use stainless fasteners, antiseize is virtually a necessity: stainless has the characteristic of "galling". You could picture this as occurring when you tighten the nut-bolt, and the adjoining surfaces begin to intermingle, almost like a slow melting together, or cold-pressure-welding. For sanity and future removal, you must use anti-seize with stainless. In summary: Antiseize makes life easier later, but requires additional locking hardware initially. My Choice for Your Application: With regular steel (or Grade 8): use Locktite Blue. With stainless, use antiseize, internal-tooth lockwashers. Hope this is helpful, -Gord ---------- more info --------------------- Karl: I actually dragged out some Loctite data sheets, to separate my fading memory and anecdotal recommendations from the hard information. Product -> 222 242 262 271 277 290 Rel. Strength Low Med High High High Med-High Shear Str. 800psi 2000psi 800psi Colour Purple Blue Red Red Red Green Viscosity 1000 1000 1500 500 6500 12 Full Cure 6 h 6 h 6 h 2 h 6 h 2 h I think only 242, 262, and 290 (Blue, Red, and Green) are applicable to this group. The 290 green stuff is meant to be post-applied to joined fasteners (it's the "ooops, I forgot to put Loctite on first" stuff!). The Loctite graphs of strength versus temperature show an interesting story: 242 loses about 10% strength by 100F, 50% by 200F. 262 gains some strength over the same region, losing 15% by 300F. 290 is only down about 10% by 400F. Solvent/Environmental resistances (percentages of full strength): Product --> 242 262 290 Air (180F), Reference 100% 100% 100% Motor Oil 100% 100% 86% Water 27% 100% 74% Glycol/Water 30% 98% 74% Transmission Fluid 100% 100% 90% Gasoline 95% 86% 90% ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ MIT Installation Dgray@semiflex.com requested info on the MIT kit. I did the switch over July 4th weekend last year. I prepared the XJ ('87 Cherokee) on Fri night. I already have a lift on the Jeep and did not require to lift it higher. I washed out underneath the truck first. It sucks when dirt falls into your eyes. Probably should wear some safety goggles. I drained out the ATF fluid, removed the rear driveshaft, and loosened the bolts. I could not break the nut off the front output shaft of the transfer case. The next morning, I tried to remove the front output shaft nut but could no break it. It takes if I remember right 120 ft-lbs. For this step I suggest that you shift it into 4wd low and lock your rear wheels and then try to break it. I was able to maneuver the new shaft with chain attached and place the chain over the front output chain teeth successfully after 15-20 minutes of playing with it when reinstalling it. When I removed the rear bearing retainer, I checked for problems. I did find that the filter to the pump was contaminated from the overusage of the silicon sealer from the factory (assumption that this was never opened). I maneuvered the output shaft and chain out from the transfer case. This came so easy that I thought the chain was stretched. I called several Jeep dealerships and spoke with the tech in the garage on the length. I was in specs. I cleaned out the rear of the transfer case from all debri by using long needle nose pliers, ATF in a stream bottle, and paper towels. When its mass assembled, it gets dirty inside. I then proceeded to remove the snap ring without ring pliers. Using several sizes of flat screwdrivers it finally came. It was distorted a little but some vise grips took care of that. I reinstalled the sprockets onto the new shaft and fit was not a problem. Make sure that you inspect how the sprocket set is on the original. I attached the snap ring back in with some difficulty and placed the shaft and chain into the transfer case. It took some maneuvering but I got the chain over the front output sprocket and secured the new shaft in the transfer case. I attached the rear bearing housing and applied orange silicon (high temp) to seal the aluminum housing. Make sure that both surfaces are CLEAN and DRY. I had to peal a lot of old silicon off the bearing housing. I checked to make sure the bearing were clean also. I ran them under a small stream of old filtered ATF to clean them up. No markings except from where they ran-very little play in the balls. Assembled the rest as instructed and torqued everything. Maybe it took 3-4 hrs to do. I did this on my back in a townhouse community. My truck was not in front of my house and the back and forth trips for tools took lots of time. Plus it was really hot that day - July 4th weekend you know in northern Virginia. Then I measured the distance as instructed and took this to the driveshaft shop. I dropped off the old rear driveshaft, gave him the measurements and the hardware provided by MIT. I returned 1.5 hours later and got a two piece driveshaft. He did mention that the original shaft was bent. I installed it with no problems. Did a test run and no problems. Since the install, I had no problems with the vibration or shaft. I did have a slight leak in the bearing retainer area. I suppose that I didn't put enough silicon sealer there. I just dried out the leak with towels and blow dryed it with the ARB pump. Then scweazed (sp?) some silicon into the leaking area. No more problems. The kit itself is $500 and modified driveshaft $200 and my own labor. If you have the right tools, you could probably have it ready via noon Thursday starting Wednesday evening and save yourself the extra $$ and have the OBS (Owner Built Satisfaction). STRONG SUGGESTION, I would not predict the length of the rear driveshaft without an exact measurement. This could damage the new rear driveshaft in compression or extension. Measure it for safety. Michael J. Moran A couple of nights ago, Gord Pritchard and myself installed an MIT kit into my '91 YJ (bought from Todd O'Connor around 6 months ago...took me long enough, eh Todd?). Prior reports indicated that it required approximately 4 hours at a leisurely pace and it was a 1.5 banana job. Well, it took us longer than 4 hours but the banana rating was right on. The key to making this job easy is to have the right tools. One of the first surprises I encountered was that many of the bolts involved in this job were _metric_. Pretty strange for a transfer case which is made in the US. Secondly, it required a few socket sizes which I didn't have but, fortunately, Gord did. Oddball sizes included a 1 1/8th and a 30mm. I had read the installation instructions three or four times before starting the job so I felt familiar with what was needed and even saw a couple of ways to make the job go faster (more on this later). The first thing to do is make sure you have the required materials: ATF Dextron II and some RTV. Next, shift the xfer case into 2-Hi and remove the front driveshaft and yoke. I didn't think this was necessary because I didn't see anything in the instructions which would require it's removal SO I LEFT IT ATTACHED. We then attempted to drain the case but, since I didn't have my Jeep manual, we weren't sure which bolt was the drain plug. Common sense prevailed and we chose the lowermost bolt on the rear face of the case. We struck oil...or rather, ATF. The next thing to come off was the rear driveshaft. Having done that, we then removed the drive cable and sensor for the speedometer. After that, the instructions called for the sliding yoke tail housing to be removed. Again, I thought this was redundant because it would be removed with the rear bearing retainer anyways. Besides, I removed the bolts for the tail but couldn't break it loose. So I unbolted the bearing retainer (which is also the mounting point for the speedo cable) and pried it loose. Unfortunately, I couldn't pull the retainer completely free from the xfer case because inside the tail housing was a snap ring which was preventing the retainer from sliding off. Aargh. Okay, so maybe the instructions were right. I put a few bolts back into the retainer to hold it tight while I proceeded to whack the tail housing with a block of wood and my metric hammer. I eventually loosened it with a strategically placed pickle fork. It attempted to take me out by jumping off the output shaft and aiming for my head but I blocked it with my cat-like reflexes. Having conquered this obstacle, we were then free to remove the bearing retainer. Wow, we were almost half-way done. The bolts for the rear half of the xfer case removed and, after some dirt was s craped off, we found the two pry notches where we could insert flat-blade screwdrivers and easily pop the case. The wonders of the xfer case awaited. Looking inside, however, was anticlimactic. Basically there were two big gears, a chain, and a couple of shifting forks. Ok, so we simply had to slide the main output shaft, chain, and front-drive output shaft backwards in order to slip the chain off the two shafts. Huh? The front output shaft had to be moved backwards?? Uh-oh. That's right...that's exactly why the front driveshaft and yoke had to be removed. So I reluctantly slid to the other side of the case and disconnected the driveshaft. With the skid plate mounted under the xfer case, a LONG, STRONG ratchet wrench extension would be required to remove the nut securing the yoke. Naturally, we didn't have one so I went ape-sh*t on the rear output shaft, jiggling it furiously while I ever so slowly worked the chain off the front output shaft. After nearly pinching my fingers between the gear and chain, the chain was in my hands! The rear (main) output shaft was then removed. We removed the snap ring which retained a larger gear and synchronizer and moved those components onto the shaft supplied by MIT. Oh, this would be a good time to talk about the snap rings. I bought a snap ring plier with interchangable tips in preparation for this job. As expected, it wasn't what I needed. Mine was designed for rings with the little holes or notches in the ends. The ones used in the xfer case were simply angled at the ends. -- -- ---+ +--- \ / <- like this o| |o <- not this --- --- ---+ +--- We were able to use a combination of my inappropriate snap ring pliers and Gord's nicely honed flat blade screwdrivers to remove the rings but that's no reason for you to do it this way. Get the right pliers. Despite Gord's disapproval of my slovenly ways, I lightly wiped off the parts before starting the installation. Gord would have preferred that I use a parts washer but since I didn't have one, I used my sister's old "Miss Piggy" [tm] beach towel. Oh yeah, we also scraped the old RTV off the mating surfaces before re-assembly (I'm not THAT slovenly). Slipping the chain back onto the front output shaft was just as annoying as removing it but it eventually happened. The case half went on without a hitch as was torqued to 30 ft-lbs. The rear bearing retainer was trickier because it required careful alignment of the oil pump. Each time I almost had the retainer on, the pump's teeth would slip off the shaft's splines. We finally got it on by one of us holding the pump in place with a thin scredriver while the other pushed the retainer on. The bolts were torqued to 18 ft-lbs. Finally, we put some RTV on the splines of the larger,MIT yoke, greased its seal, and torqued it to 130 ft-lbs. The speedo cable was re-attached and I filled the xfer case to the bottom of the fill hole with ATF Dextron II. At this time I'd like to point out that I did something right by buying a screw-on flexible tube for my 4L container of ATF. With this tube, I could easily fill the case by simply raising the container and squeezing. In total, it took us just over five hours to install the kit. Oh, and I owe Gord a case of beer (the preferred currency among STHMs). ...lars ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Removing dash speakers Does anyone on the list have experience removing the in-dash 4x6 speakers on the Wrangler? (grin) I just replaced the speakers in my '91 this week. You're right; the person that wrote that manual never ever tried the procedure. There's just not enough room. On the passenger side (the first one I worked on), simply removing the three bolts that hold the end of the dash to the tub, and the windshield retaining plate allowed the dash to be pulled forward enough to get the extra inch of clearance required. Not so on the driver's side. I had to take the whole dash loose. Note I did *not* have to remove it; just had to loosen it. The procedure I used was: 0. (forgot to mention this step) Do go ahead and remove the parking brake. 1. Do the work required to fold the windshield down (different if you have a hardtop or a softtop). 2. Remove the torx head bolts that secure the dash. There are six or so along the top and the three at each end. 3. Remove the phillips screws that secure the dash pad to the dash. Note here that I'm only talking about the ones that were concealed by the windshield. If you leave these in, a couple will hang up and keep the dash from moving. 3.5 (forgot another step!) There was an electric component mounted with velcro on a aluminum plate right next to the brake release. I removed the plate. This may have been put in as part of the air conditioner install; you might not have one. 4. Now you should be able to lift upward and tug backward and move the dash into the passenger compartment by about an inch or two. It'll still be a tight squeeze, especially on the driver's side where a large wiring harness is in your way. But with only a small amount of cussing, I was able to get to both speakers and replace them. This really isn't all that tough. It's just a bit tedious. The most aggravating part was that there's a chunk of the body sheet metal that's only a couple inches away from the back of the speakers even after you do the dash loosening. The speaker magnets want to grab on to it just as you think you've got them on the mounting screws. Mike Whitten ------------------------- It isn't easy but you can get your arm up to the speakers by kneeling on the ground by the rig with doors off and reaching up under the dash. EXPECT some bleeding there are lots of sharp edges up there. I built a small wrench out of a 1/4 inch socket set. I welded a small "t" on a 3" 1/4 drive extension. I installed Sony plate speakers in the stock positions. And I did not have to remove the E-Brake. Dave Taylor ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Ring & Pinion Gear Upgrade I just recently did a lift and new ring and pinion on my 92 Wrangler. I have seen a few questions about how hard it is to install ring and pinion for the first time, so I thought I would write it up. This wasn't exactly my first time, within the last month, a friend of mine broke teeth off his 44 pinion, so he was my guinee pig. Before getting into the r&p, I want to comment on the lift and my lock right. I installed 2.5" lift, Skyjacker Softride springs and Rancho RS5000 shocks. It rides very good, in my opinion, at least as good as stock. Also, I have a lock right in the rear and have been very curious as to how it was holding up. It has about 25k miles on it, and I was glad to see very little wear. Within the last 3 or 4 months, I have been buying parts and tools I need to do the job. Some of the tools needed aren't that hard to make, so I saved some cash and made them myself. Below is a list of all the stuff I needed for doing the ring and pinion: ring and pinion front & rear (used w/5k miles)$150 pinion/carrier shims, seals, 35 carrier $175 factory service manual $ 65 4 5/8" bearing seperator $ 50 hydraulic press (made) $ 40 case spreader (made) $ 20 bar to hold yoke for tightening pinion nut (made)$ 10 tube to press on pinion bearing (made) - plug for end of carrier (made) - puller to use with bearing separator (made) $ 10 calipers for measuring shims borrowed dial indicator borrowed work in/lbs torque wrench borrowed 250 ft/lbs torque wrench rented I went from 3.07 to 3.55 gears, so I needed a new rear carrier for my lock right. I didn't change any of the pinion/carrier bearings because the jeep only has 55K miles, but I did put in all new seals. Putting in all new bearings front and rear would probably be > $250. The factory service manual has very good detailed instructions for setting up the ring and pinion. I had a general idea of how it was done, so the manual made sense, and answered all my questions. Most of the stuff I made wasn't too hard, but I do have an arc welder, and access to the machine shop at work. I needed to use a lathe to make the tube to press on the pinion bearings, and to make the plug for the end of the carrier. The plug goes into the end of the carrier, so the puller has something to push on. The press isn't absolutly needed, but it makes pressing bearings very easy. The case spreader also isn't absolutly needed, but makes it easier to get the carrier in and out. The bearing puller is needed to pull the carrier and pinion bearings. The manual used a special bearing puller, where I used a standard bearing seperator and fabricated puller. The only problem with using a bearing seperator is that you can screw up the shims under the bearing if you aren't careful. The yoke holder is something you cannot do without. With the housing sitting on the bench, you need something to hold the yoke while tighten- ing the pinion nut. I started with the 35C rearend. I did not need the case spreader to get the carrier out. I used 2 large screw drivers to pry it, and it popped right out. The 35C is easier to setup because the carrier shims are on the outside of the carrier bearings, so you don't have to pull the bearings to change the shims. When putting in the new pinion, I didn't have to change the pinion height shims because the offset on both pinions was 0. As outlined in the manual, if you are changing pinions, you don't necessarily have to measure the pinion height. There is a number scribed into the end of the pinion which is the offset from the perfect pinion height. So to get the pinion height correct, just take the difference between the old pinion and new pinion and adjust the shims. The 35C has a crush washer for pinion bearing preload. To get the preload correct, you tighten the pinion nut until it takes about 15 inch/lbs to rotate the pinion(if using new bearings, it is a little higher). After the pinion was in, I needed to determine the carrier shims. The procedure is to install the carrier with bearings installed (no ring gear), and shims for a starting point on each side. The manual says to start with .080 thick shims on each side, but the shim set I bought only went down to about .140, so I used the 2 thinest ones. Now the dial indicator is used to measure the total play side to side to determine how much to add to each shim. I did this, adjusted the shims(also adding .004 to each side for preload), then installed the ring gear. Then I measured the backlash with the dial indicator and it was .004. The spec is .005 to .010, so I adjusted shims and got it to .006. The last step is to check the gear pattern, I used prussian blue marking compound. The pattern shows if the backlash and pinion height is correct. It isn't real easy to get a good readable pattern, but I was satisfied with mine. Now for the front 30. I have an ARB in the front, and was hoping it wouldn't cause me any problems. To remove the carrier, I had to use the case spreader. I tryed prying it out, but it was pretty tight. I spread the case .010, and it came right out. I then removed the pinion and pulled the bearing. Now it was time to replace the seals. There is 1 seal in the tube next to the carrier, and 1 on the outboard side of the axle disconnect. Both seals were easy to remove with a long metal rod. I used a large socket to tap in the seal next to the carrier. The axle disconnect seal was a pain because of its location, and that a special tool is required. I finally got it by grinding a piece of metal the same OD as the seal, and taping it in with a long metal rod. The new pinion had a different offset than the old pinion, so I had to adjust the shims accordingly. On the 35C, the pinion shims were under the inner pinion bearing, but on the 30, they are under the inner bearing race, so I knocked out the race, and adjusted the shims. The 30 uses shims for pinion preload, and I decided to try and use the same shims. I installed the pinion, bearings and shims, and tightened the pinion nut to about 200 ft/lbs. To see if the preload was correct, I measured the torque(in/lbs) to turn the pinion, and it was OK. The next step was to install the carrier and adjust shims. Because I was using the same carrier and bearings, I decided to install the new ring gear and see how close the backlash was. This way, I wouldn't have to pull the bearings on the carrier. The backlash was right on at .007. The standard procedure is to install the carrier without any shims under the bearings and no ring gear, then measure the total movement side to side using the dial indicator. There are master bearings you can buy that don't require pressing on to make the measuring easier. Then you would install the ring gear and measure the play between the ring and pinion, to determine the ring gear side shims. The other side shims is the total play minus the ring gear side play plus .015 for preload. When I was all done, I checked the gear pattern, and it looked fine. So, setting up ring and pinion is doable if you haven't done it before, but having the right tools and completely understanding the process is very important. The complete job, which included the r&p, suspension and a few other things, took me about 3 days. Don Graham ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Ring & Pinion Gear Installation Tips Does anyone else hve tips, tricks and home made tool tricks for doing a ring & pinion installation? Kevin Alcox writes: A 4 poind or better "dead blow" hammer really makes things go together better when you don't use a housing spreader. Also, using a brass drift and/or punch will prevent damage to any sensitive surfaces. John Nutter writes: The last time I replaced a pinion seal I made the tool out of an piece of angle iron. I just drilled 2 holes in it to match where one of the U bolts goes. It worked fine. John H. Stewart writes: Having accomplished this job, a few points were learned: 1) DANA/SPICER has a pamphlet detailing differential tear-down, rebuild and setup. VERY helpful. 2) Replace ALL of the bearings and races while it is dis-assembled. 3) Use NEW carrier bearing shim packs. 4) Repalce ALL oil seals while it is dis-assembled. (The pinion seal will be destroyed when removed; however, there are axle seals that should be replaced. The Dana 30 has two in the differential. The Dana 44 has two at the ends of the axle tubes.) 5) Measure ALL shim packs as you remove them. 6) When you remove the bearings from the carrier, try to save them, OR get an extra set. Setting the shim pack is easier if you have a spare bearing set to use. You will need to ream out the inside in order to allow an easy slip-on/removal of the bearings from the carrier in order to adjust the shim pack. With shim measurements, take into account the thickness of the bearings. 7) The pinion is marked with a number (+1, +2, -2 or something else). Look at the one your are removing, it will have a similar number. The difference between those numbers is the adjustment in shims you will need to do. That is where the DANA/Spicer pamphlet is helpful; it has a table explaining the equation factors. 8) MARK the carrier bearing hold-down clamps before removing them. They must be replaced exactly. 9) Find a machine shop to press off old bearings and press on the new bearings. As far as "special tools", just having a micro, dial guage, slide hammer, bearing removal/insertion, and the "normal" assortment of other hand tools, nothing special is required. The carrier may need a little physical effort to remove using leverage and a pry bar, so a case spreader is not required. You may need a clamp to position the dial guage for measurement. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Roll Cage Mounting A couple of years ago when I was trying to figure out what to do about my roll cage, I considered attaching it to the frame. I asked on some list or news group and every response I got said that this was a *bad* idea. Apparently, the feeling was that you don't want the body directly attached to the frame which this would, in effect, do. Does anyone have any thoughts on this? I'm getting a new floor and could make cleats for a direct frame attachment. BTW, I am also planning on mounting my seats to the cage. Any downside? Richard ------------------------------ How about attaching the rollcage to the frame using body mounting rubber? As long as you have a body mount between the frame and the rollbar "foot" then the body can still be able to flex independently from the frame and the rollbar will be bolted to something better than just the sheetmetal body. This is how I did my rollbar in my Scrambler. It works really good. Let me know what you think. Jerry Miller ------------------------------ IMO probably the best way to mount the cage to the frame while maintaining the body isolated is similar to the desert racers "modular triangulated" approach where sections are connected via polyurethane bushings in tubular mounts. "Ears" are welded to the hoops and the down bars or kickers have short pieces of tubing welded at 90 degrees, making a long skinny "t", the cross piece has (usually) a poly bushing inserted and the assembly bolts in place between the ears. The beauty of this system is that individual sections can be removed (down bars in a pickup if you need bed space) with relative ease, plus the body remains free floating from the rigid frame/cage. Too much fabrication? Autofab has the parts complete with bushings, just weld appropriate parts together, insert bushings and bolt together. Terry Rust ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Transmission Bushing - It's Supposed to be Loose! If you spend some time looking for a source of noise/clunking/vibration under your YJ, you may discover a pair of loose bushings attached to the transmission where it mounts to the skid plate/cross member. Looking from the front of the Jeep, these two bushings sit to the right of the rectangular rubber block which is actually the transmission mount. This block should NOT be loose. The two bushings provide a cushion for a kind of an outrigger which limits the torque-twist which may occur in the tranny. These two bushings will have some play above and below the "outrigger". They are NOT supposed to be tight. I don't want to explain how I know this. <g> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ What is Involved in Lifting My Wrangler? Complete lift kits usually come with the following: - Four spring packs (note: Add-a-leaf kits use the existing spring packs and insert a single, heavy leaf into each pack. While cheaper than four new packs, add-a-leaf kits are generally very stiff-riding). - Longer shock absorbers. - Longer u-bolts (for mounting the axle to the leaf springs). - Extension brackets for the front and rear track bars (also known as panhard rods). - Brake line extensions or re-mounting brackets to provide extra length. - For lifts of 3" or more, a drop-down pitman arm. - For lifts of 3" or more, longer sway-bar links. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Vacuum Hose Tips I find that every 4 or 5 years it helps a lot to replace all of the vacuum lines. Get a bunch of vacuum line and systematically replace *all* of it. This might be obvious but it wasn't to me: do one line at a time. Find one end, trace the hose to the other end, remove it and cut a new one the same length as the old one. Then replace it. That way you won't be scrambling for a vacuum line diagram because you took off all the vacuum lines. Finally, get a bunch of nylon cable ties. Cinch the cable ties over every hose connection. This will make your motor idle a lot smoother because you won't have any vacuum leaks. I've done this on every vehicle I've owned and it made a noticable difference. I had an econobox that would not idle smoothly. I replaced all the vacuum lines and it still ran rough. Then I cabled tied the vacuum connections and it purred like a kitten. I've done it ever since... Bruce D. Oborn P.S. If it's burning oil, replace the PCV valve. If the valve fails you can suck oil into the air cleaner. If it still burns oil with a new PCV valve it's time for a compression test. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Windshield Leaks & Replacing the Glass Edward wrote... >I hope someone can help me. My problem is there is a leak on the >driver side of my jeep. Right now I have my hard top on. I have >already replaced the rubber cowl this did not help. I hope someone >can help. Edward, It would help if you were more specific about where it leaks. My YJ leaks from behind the windshield brackets, and runs right down over the speakers. Any way, if it's the same problem I had, you're in for a real treat. On the YJs, the windshield doesn't seal around the edges, it actually seals behind the glass, the rubber strip on the outside of the frame is pretty much for cosmetics. Problem is, this setup lets water sit behind the strip. When I pulled this strip I found 4-5 holes and much rust. I ended up pulling the glass, sanding, rust treating, priming, painting, and reinstalling the glass. If you end up doing this, here are some hints that I wish someone had given me... 1. Get a 'windshield mounting package' from the dealer- #83100051 (~$15) among other things, it contains small spacer/standoffs that locate the glass while the adhesive is curing 2. Use the urethane adhesive in the tube, I found this much easier to work with than the preformed bead you get at parts stores (it's about $12 for a 14oz tube for your caulking gun) 3. Be sure to clean the glass with acetone or something like it (note, all prices are $US) I just hope that when it rusts out again (I give it 2-3 years) there'll be a fiberglass replacement for the windshield frame. If I'm mistaken and someone makes one now (for the YJs), please let me know! Rich White '89 YJ 4.2L ------- >My '88 wrangler has a leaky windshield that is getting worse >as more rain falls here in "sunny" California. The water >enters the cockpit from the bolts holding the plates that >hold the windshield to the dash. My question is: is the water >entering via the gasket on the windshield glass (the glass was >replaced about 4 years ago) or is it entering via the windshield >frame-to-body gasket? Any ideas? Thanks! What a coincidence, I was going to make a report on my 1988 Wrangler with a leaky windshield today. Mine was leaking buckets before I sealed the frame-to-body gasket with clear silicon goop. I put it under the gasket all along the windshield. Then pressed the gasket to distribute the glue and push the excess glue & air out. This morning it was raining cats & dogs here and there was no puddle waiting for me on the floor. So far, so good. Some say that the water can also come in from the rubber seal around the windshield. Use the Permatex flowable silicon seal for that. If mine leaks anymore, I'll do that. It might be worth your while to do both at once. Good Luck . . . Dave ---------------------------------- Assuming you mean the CJ/YJ type of Jeeps, check the rubber seal between the windshield frame and the body of the Jeep. I think every Jeep eventually leaks through here. The cheap and quick fix is to put the window down, lay a nice big, thick goopy bead of silicone or other similar sealant along the seal and put the window back up. Of course, when you lay it down again you'll have to repeat the sealing process. Also, check the rubber gasket around the glass. Water often comes in there too. Again, a thin bead of silicone around the edge of the glass (on the outside) will stop that. Chris Holmes ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Air Conditioner Troubleshooting From the Chrysler FAQ From: bohdan@ihgp.ih.att.com (Bohdan L Bodnar) ====================================================== This article briefly describes the control system of computer controlled air conditioning systems which are typical of Chrysler vehicles which do not have automatic temperature control. This system is also similar to that of other manufacturers' products. The following components are used: 1). An electromagnetic a/c clutch. 2). The fan relay (the relay is a double-pole-single- throw type; 1/2 is used for fan control whereas the other 1/2 is used in the relay logic circuit used to control the a/c clutch). 3). The wide-open throttle (WOT) cutout relay. 4). The pressure cycling switch. 5). The switches used to select air conditioning: defrost and a/c. 6). The fan switch. The circuit shown below is representative: ------> to switched battery _| _) a/c clutch and surge suppressor _) ) | --- 1/2 fan relay --- | -/- WOT cutout relay /-- | |-----------> to ecm | -/- pressure cycling switch /-- | --------- | | a/c switch / / defrost switch | | --------- | | / fan switch (closed if fan is on) | ----- --- chassis ground - The point marked "to ecm" is drawn to a positive value via a pull up resistor on the computer's board. The pressure cycling switch is used to prevent ice formation on the evaporator's core (this would obstruct air flow and cause system overheating). The WOT cutout relay is a normally closed one; it is energized (opened) by the ecm if the ecm detects a WOT condition -- this reduces engine load during high power demand. The fan relay is energized by the computer when cooling is required, a/c is required, and, under appropriate conditions, for radiator demisting (to reduce steaming when the vehicle's engine is on, but the vehicle is not moving). The clutch is an electromagnetically controlled "brake" which is attracted to the compressor when current is supplied; the friction material ensures that, if the clutch is working properly, the compressor will fully engage. The surge suppressor on Chrysler products is often a pair of zener diodes mounted back-to-back in the (polarized) connector going to the clutch. Operation of the system is as follows (assume that the car is not near WOT): 1). If the fan is on, adequate pressure is present in the system (pressure cycling switch is closed), and either a/c or defrost is selected, the point "to ecm" is drawn close to ground. The computer interprets this as an air conditioning demand. 2). A timer (typically, 300 ms to 400 ms) is set. 3). If engine rpm is below a threshold (typically, around 900 rpm), the rpm is raised to the threshold. 4). Once timer expires, the fan relay is energized. The compressor is now on. The compressor will continue to be on unless WOT is reached or the pressure cycling switch opens. The process then repeats. The following readings were taken using an OTC 500 meter and OTC current measuring clamp; they are off of a 1986 Le Baron: - Clutch resistance: 5 ohms, as measured at the clutch connector. - Operating current: 2.4 amps (per Chrysler service manual: current in excess of 5 amps indicates a shorted clutch). The current will vary with system voltage. - voltage drop to battery's negative post from clutch: < 500 mv. A common failure is the fan switch's resistance increasing. Indeed, these switches are known to melt from overheating. On 1980s products, this switch is a replaceable item (about $18 -- dealer only) -- the entire pushbutton assembly does not require replacing. Here are some problems I ran across in my Le Baron: 1). BAD FAN SWITCH The switch didn't overheat, but caused an insufficient current to be delivered to the clutch. This caused the clutch friction material to overheat, which caused the clutch to float on a layer of gas. The symptoms were (1) gradual reduction in cold air delivery and (2) smoking refrigerant oil (leaking from a 9 years old compressor front seal). 2). BAD PRESSURE CYCLING SWITCH AND CONNECTIONS The pressure switch had bad intermittent connections; also the terminals in the external connector were corroded. The symptom was the a/c cycling on and off about three times per second (recall that the computer's timer is set to something between 300 and 400 ms). Copious use of television tuner cleaner and polishing the blade terminals on the switch would temporarily eliminate the problem. The fix consisted of replacing the switch (aftermarket bought from a parts jobber -- about $30), replacing the terminals in the connector (available in any hardware store), and spraying the connectors' boot with silicone lubricant (for a weatherproof seal). The original terminals were merely crimped; I crimped and then soldered the connections. TROUBLESHOOTING SUGGESTIONS You will require the factory manuals (or equivalent information) and a high impedance multimeter. If a digital meter is used, it *must* have a bar graph display since the digital display with the dual-slope integrating analog to digital converter will react too slowly to changes in the circuit. A min/max function is also useful to have. The voltage drop from the clutch to the battery's negative terminal MUST be low when full operating current is seen -- about 700 mv MAXIMUM is ok. In my case, after all repairs were made, the voltage was between 400 and 500 mv. For one test, I disconnected the clutch and replaced it with an unpowered test light -- this allowed me to check voltage drops with the a/c always on (pressure cycling switch would never open). Although full current was never approached (the light draws only about 300 ma), I did find bad connections. Measuring individual voltage drops is the ONLY reasonable approach. Once problems are found, resistance measurements can be used to home in on target components. For example, I found bad electrical contacts by isolating the problem to the pressure cycling switch, then turning off the engine, disconnecting the WOT cutout relay connector, and measuring resistance from the battery's negative post to the WOT connector. Moving the terminals on pressure cycling switch's connector showed a huge decrease in resistance. Television tuner cleaner didn't reduce the resistance too much, so the terminals were replaced. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Backfiring Hmmm ... check your ignition timing yet? Funny you would mention the EGR. I've heard conflicting stories about the effectiveness of it as a pollution control device. Moses Ludell's Jeep book says that the EGR actually lowers the temperature inside the combustion chamber, and as such makes the engine burn cleaner ... but Jack Clifford from Clifford Performance say's "it's a crutch for poorly designed aspiration (carb/intake) system" and a properly designed/tuned system will burn cleaner without it. (Since Clifford sells manifolds, headers, cams & fuel systems, I could have predicted that! <g>) One thing is certain, if the EGR carboned up, it *will* allow excess exhaust gasses back into the system. Usually removing the vacuum line won't have much effect, since the vacuum operates a bellows (diaphragm?) that opens up a pin shaped valve. If it does have an effect, then maybe the bellows is leaking ... causing a vacuum leak. To test, beg/borrow/steal a vacuum tester and hook it up to the EGR. Pump it up to about 5, and see if it leaks out. If not, the bellows is OK. The next thing to do is check out the pin, and it's seat, to ensure that it seals off the line properly. Clean it out ... anyways! Now, something that a lot of us overlook is back pressure in the exhaust system. It shouldn't be more than 7 lbs, I think. If so, either the exhaust system or the catalytic is clogged. Remember that an improperly running engine can very easily cause a catalytic melt-down. If you have to replace a cat, that's the symptom. You've got to make sure you find the cause! It usually is one or a combination of the misc things we've talked about on this list! Check it out, cause it'll cost you another catalytic if you don't. John Madill ------------------------------ If you can get rid of your rough idle and problems at higher RPM's with the EGR disconnected, then you have a bad EGR. Since EGR is a SMOG device and its function is to lower the combustion temperature, it should not cause any serious problems other than higher emissions. If you live in CA you will not pass the SMOG test with EGR disconnected since it is one of the first thing that is checked. Siamak Navid ------------------------------ Air from the smog pump will cause a backfire on decelleration. Make sure the bypass valve is working. It is in the hose that runs from the smog pump to the AIR manifold (it has a vacuum line on it.) The vacuum source is manifold, not ported. Apply 22" vacuum to the fitting and make sure it will hold vacuum. With the vacuum applied, the valve should close (preventing the smog pump from pumping air into the manifold). Lenny ================================ I can tell whenever I have a exhaust manifold leak because I start backfiring like an old model-t. I replace the manifold gasket and it stops. Which brings up another question. Anyone out there know how to seal headers up well? I have a 225 v6 and always seem to have leaks, even with new gaskets. Warped headers maybe? Bruce D. Osborn ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Diagnosing Electronic Ignition Systems From the Chrysler FAQ Let's go to the fundamentals before troubleshooting. On EVERY EFI engine, the computer expects to see pickup pulses (from crankshaft position sensor if DIS system or distributor if not) if it is to activate the fuel pump beyond the fuel system priming stage and to provide spark. Chrysler is not different. Here's what I'd do: 1). Pull fault codes and see what's causing the problems. You may not have any codes stored... 2). Disconnect battery for about 30 seconds and then crank the engine. 3). Pull codes; is code 12 (working from memory here...) present? This code is an " informational" code which states that the engine was not cranked since the battery was last disconnected. No distributor pickup pulses, no cranking evident to the processor ==> code 12. 4). Alternative procedure to see whether distributor pickup signals are present: listen for fuel injector cycling while cranking. Lack of pickup signals will result in no injector activity. 5). Suppose your diagnosis suggests that the ECM is not seeing pickup signals. In *my* case, I'd stick an oscilloscope across the pickup and see whether I have a pulse which is not riding on a DC pedestal; i.e., it is switching cleanly between *power* ground and the voltage which is supplied to the Hall Effect pickup in the distributor. If it's riding on a pedestal, I'd locate the poor ground connection and fix it.L 6). If a signal is not present, then I'd look at the pickup supply (my recollection is that is 8 volts...could be 5) WITH the pickup disconnected, I'd do a resistance test between the signal ground and power ground. If pickup power and ground are ok, then either the pickup has failed (most likely) or there's a bad electrical connection in the pickup's connector (less likely). Bohdan Bodnar ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Diagnosing Problems With Computer-Controlled Carburetors From the Chrysler FAQ From: bohdan@uscbu.ih.att.com (Bohdan L Bodnar) This is a description of the procedure I've used to diagnose air/fuel mixture problems in computer controlled carbureted engines; the outlined procedure can also be used to set the idle air/fuel mixture without resorting to infrared exhaust gas analysis. The procedure is based on the General Motors " System Performance Test" which was developed for diagnosing problems in GM's carbureted engines. This procedure will not work with carburetors which use a stepping motor to control the a/f mixture (e.g., Ford's variable venturi carburetors). THEORY The a/f mixture is controlled by a MIXTURE CONTROL SOLENOID (MC solenoid). This is a valve which operates at a fixed frequency (typically, 10 Hz) and whose duty cycle (valve's ON time divided by period) is varied. That is, the valve is pulse width modulated. When the valve is turned on, the incoming a/f mixture is fully leaned; when off, fully enrichened. The former is called a "lean command" whereas the latter is called a "rich command." By varying the duty cycle of the MC solenoid, the AVERAGE a/f mixture can be varied. In GM products, this valve directly varies the incoming fuel and air flow. In Fords, only the incoming air is directly varied. In Chryslers, only the incoming fuel flow is directly varied. The valve has a two wires electrical connector. On wire is connected to switched battery voltage whereas the other is connected to a power transistor in the computer and is a source of switched ground. During closed-loop operation the following will occur (assume the oxygen sensor is sensing a lean condition -- its voltage will be low): 1). The computer gradually decreases the MC solenoid's duty cycle. 2). The exhaust eventually becomes rich enough that the oxygen sensor's output will swing high (about 1 volt). 3). The computer gradually increases the MC solenoid's duty cycle. 4). The exhaust eventually becomes lean enough that the oxygen sensor's output will swing low (about 0 volt). The cycle now repeats. A device for monitoring the solenoid's duty cycle (such as a dwell meter) will show a constantly varying duty cycle. The frequency of the oscillations will depend on the how fast the computer varies the duty cycle and the engine's RPM. An AVERAGE duty cycle of 50% corresponds to, on the average, NO average a/f correction. Stated differently, everything is operating correctly. An average duty cycle of LESS THAN 50% corresponds to, on the average, a rich command (the computer is compensating for a lean condition). An average duty cycle GREATER THAN 50% corresponds to, on the average, a lean command. DIAGNOSIS AND SETTING IDLE A/F MIXTURE Monitoring the MC solenoid's average duty requires (for most people) the use of high impedance dwell meter. A low impedance dwell meter may be used unless it affects engine operation; my recommendation is to not use a low impedance dwell meter (that is, stay away from self-powered dwell meters). Following the GM procedure, set the dwell meter to the six cylinders scale REGARDLESS of the number of cylinders in the engine. At this setting, 30 degrees will correspond to a 50% duty cycle, 60 to a 100% duty cycle, and 0 to a 0% duty cycle. Run the engine until closed loop operation is present; this will be indicated by a varying dwell (see footnote 1 for deviations from this procedure). Once the engine is hot, not the average dwell -- the reading should vary equally above 30 degrees and equally below 30 degrees. The following is a brief trouble listing: 1). DWELL NOT VARYING: system is operating in open loop. 2). DWELL STUCK AT 10 DEGREES OR LOWER: full rich command is present; the computer is compensating for WHAT APPEARS TO BE a massive fuel flow reduction (check for dirt in carburetor, air injection system stuck in upstream position, vacuum leaks, improper a/f mixture setting...). 3). DWELL STUCK AT 50 DEGREES OR HIGHER: full lean command is present (check for float stuck low, valve seat damage, oxygen sensor's sense lead shorted to battery voltage, etc.) 4). DWELL OSCILLATING, BUT AVERAGE READING IS BELOW 30 DEGREES: average rich command is present (check for vacuum leaks, dirt in carburetor's jets, improperly set a/f mixture...) 5). DWELL OSCILLATING, BUT AVERAGE READING IS ABOVE 30 DEGREES: average lean command is present. Check for incorrectly set a/f mixture, float stuck low, valve seat damage, clogged air filter, etc...). Based on the above descriptions, it should be fairly clear on how to set the idle a/f mixture: merely set the mixture so that the average dwell is 30 degrees. Now, suppose the system's dwell is not varying, but the sensors are working properly, the upper radiator hose is hot... Several cars with small engines have the oxygen sensor mounted fairly far away from the engines. Indeed, during idle conditions, the sensor may cool off to the point that it will not operate (I had this experience in a 1986 Mustang with 2.3 liters engine and EEC-IV system). My recommendation is that all electrical accessories be turned off (so as to provide a minimal load on the engine) and use the idle stop screw on the carburetor to gradually increase the idle rpm until the sensor begins oscillating. Ensuring a negligible load on the engine guarantees that the carburetor will be operating mostly on its idle circuit. Now, set the a/f mixture so that the average dwell is 30 degrees. On the Mustang, this was done at about 1500 rpm. Note that the a/f mixture setting procedure assumes that NO fuel delivery problems (vacuum leaks, clogged carburetor, etc.) are present. FOOTNOTES [1] In some engines (e.g., GM cars with the "min-T" system -- Chevette) the a/f mixture is varied REGARDLESS of whether the engine is in closed loop operation or not. Consider setting the a/f mixture or diagnosing at a slightly increased rpm. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Diagnostic Codes From the Chrysler FAQ Start with the ignition off. Within five seconds, switch the key on, off, on, off, on. (On is not start!) The "check engine" light will flash. Count the flashes Each code is a two digit code, so a (for example) 23 would be FLASH FLASH <pause> FLASH FLASH FLASH <loong pause> It will never flash more than 9 times, watch for pauses! 55 is end of codes, 33 is normal if you dont have air conditioning. Please note that some codes are NOT included below, this is not a complete listing, but it IS very close to complete. 88 Start of test (This only appears on DRBII, it's not blinked out) 11 No ignition reference signal detected during cranking (bad hall effect) OR timing belt skipped one or more teeth; or intermittent loss of either camshaft or crankshaft position sensor 12 Memory Standby power lost (battery cable disconnected) 13* No change in MAP from start to run 14* MAP sensor circuit open or shorted; voltage too low 15 No speed/distance sensor signal 16* Loss of battery voltage detected with engine running 17 Engine stays cold too long (bad thermostat) 21 Oxygen sensor signal out of range, possibly shorted 22* Coolant sensor signal out of range (or disconnected to set timing) 23 Intake air temperature signal out of range 24* Throttle position circuit out of range 25 Automatic Idle Speed (AIS) motor driver circuit shorted or target idle not reached, vacuum leak found 26 Peak injector circuit voltage has not been reached 27 Logic module fuel circuit internal problem OR 27 TBI injector does not respond properly to control signal 31 Evaporator Purge solenoid circuit open or shorted OR Evaparator solenoid circuit 32 EGR system failure OR Power loss lamp open or shorted 33 Air conditioning clutch relay circuit open or shorted 34 Speed control vacuum or vent solenoid circuits open or shorted 35 Cooling fan relay circuit open or shorted 36 Wastegate control circuit open or shorted 37 Shift indicator light failure, 5-speed (blown bulb) OR Park/neutral switch failure OR 37 Torque converter unlock circuit open or shorted, A-413 4-speed auto 41* Alternator field control circuit open or shorted 42 Automatic shutdown relay circuit open or shorted 42 Fuel pump relay control circuit 42 Fuel level unit - no change over miles OR 42 Z1 voltage missing when autoshutdown circuit energized (whatever that means) 43 Peak primary coil current not achieved with max dwell time OR 43 Cylinder misfire 43 Problem in power module to logic module interface 44 No FJ2 voltage present at logic board OR 44 Logic module self-diagnostics indicate problem OR 44 Battery temperature out of range (see Note #1!) 45 Turbo boost limit exceeded (engine was shut down by logic module) 46* Battery voltage too high during charging or charging system voltage too low 47 Battery voltage too low and alternator output too low 51 Oxygen sensor stuck at lean position OR 51 Internal logic module fault ('84 turbo only) 52 Oxygen sensor stuck at rich position OR 52 Internal logic module fault ('84 turbo only) 53 Logic module internal problem 54 No sync pickup signal during engine rotation (turbo only) OR 54 Internal logic module fault ('84 turbo only) 55 End of codes 61 "Baro" sensor open or shorted 62 EMR mileage cannot be stored in EEPROM 62 PCM failure SRI mile not stored 63 Controller cannot write to EEPROM 64 Catalytic converter efficiency failure 65 Power steering switch failure * Activates Power Limited/Check Engine light. These codes cover multiple years and engines (2.2l, 2.5l, 3.0l). NOTE #1. The power module has an air-cooled resistor which is used to sense the incoming air temperature. This information is fed to the logic module and is used to control the duty cycle of the field current in the alternator. This code applies ONLY to alternators whose voltage is computer regulated. The battery voltage is sensed by the logic module -- there is an internal takeoff from the wire feeding the NVRAM keep-alive power circuit which is fed to a voltage comparator. So...if you lose the feed to keep RAM information stored when the engine's off, you also lose battery voltage sensing. -- Bohdan Bodnar ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Engine Quits Intermittently > I'm having a problem with my Wrangler. I have the 258-6 cyl. > There is an intermittent problem where the voltage to my coil > just stops. I can be driving down the road at 55 mph and the > engine just quits. No sputtering or anything, it just quits. My 89 went through the same thing. You will probably also notice that your tach goes to zero. This is all symptomatic of the ignition module failing. It's only about a $25 part at a parts store, so its an easy/cheap fix. One thing to watch for, often the parts stores will have the correct module, but the connectors won't match. The actual ignition module is the same as is used in Fords. It just has different connectors. If you can't find one with Jeep connectors, just make an adaptor harness using the wires off of the old unit. I had three modules fail in five years. After the sorry F*ing! computer carb, this is the weakest part of the engine. (Wait until your clutch slave goes! It's mounted inside the bellhousing, so you have to drop the transmission to replace it...) - Steve Holzworth ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Fuel Gauge Sending Unit Not Working It seems about a month ago there was a thread on how the gas tank repair had messed up the sending unit. My roommate had this problem when he took his wa'89 YJ in for the recall work. His gauge would read fine for the first half of the tank and then stop moving. He took it back to the dealership and the said they replaced the sending unit, but the problem was not solved. He pulled the tank this weekend and found that the float was hitting the little tub that the inlet screen sits in. If he put the float on the other side it would move down all the way (inside the tub), but it would not go up all the way since it hit the wire for the sending unit. Maybe there are some subtle differences in sending units over the years and some work with the new tank. He ended up just ripping out the tub (which probably wasn't the best solution since it probably keeps the big chunks out. The gauge works great now. Terry L. Howe ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ High Idle When Starting (4.0L) The idle air control valve requires cleaning periodically or else the engine revs very high on start up. The valve is located on the front of the throttle body (looking into the engine bay from the front) to the left of the throttle position sensor. There are just a couple of Philips screws holding it on. When it's off, I just wipe off the cone end and clean the hole it covers. When the revs are high on start up and it doesn't idle back down I usually find that there is a glob of oil/carbon or something preventing it from closing the air bypass hole. - Jamie Lawson ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Rough Idle / Stalling On my 89 YJ I6: I had a rough idle stall problem which I have finally fixed. I suspected the Pulse Air System to be the culprit. It turned out to be a simple Dirty Carb problem. Muddy water was splashing up through the underside of the Air Cleaner assembly, where the center holddown bolt is. I patched that up with silicone and a rubber washer. I still need to test this out with the garden hose. I replaced the carb with the factory rebuilt. Now to the point of this posting... The rebuild installation went without a hitch. But I was still a little paranoid of the Pulse Air system going bad and costing me another carb. So this is what I did... I got a pair of PCV breather filters (Purolater B13131) and a pair of 3/4" rubber end caps. I disconnected the two Pulse Air feeds from the Air Cleaner assembly. I plugged the Air Cleaner holes up with the endcaps. I placed the PCV filters on the ends of the Pulse Air feeds. (One feed, the down stream, goes to the catylitic conv, the other, the upstream goes ahead of the catylitic conv.) Walla (sp), No pulse air system is gonna gunk up my carb. Now if the Pulse Air valves break they wont be sending hot catylitic conv or exhaust fumes to my carb. I may put some type of breather cover over the PCV filters and affix the tubes to the fire wall to make them more water proof. Total cost $10. Donald Yerger >My friend has a 91 YJ Renegade witha 4.0 and a auto tans., His idle >seems to fluctuate when the Jeep is in park or when it is in nuetral.The >setup is still stock. Could it be caused by a leaky exhaust (which he >has) or possibly a fuel filter ar is this something that might go deeper >than this? If it has an oxygen sensor, and if the leak is before it, then this could be the problem. At idle, the leak could allow air into the exhaust system and fool the sensor into thinking there it too much oxygen in the exhaust, so it tells the FI system to change the mixture appropriately. Joe Sand > The engine starts easily. But in cold weather, after just a few > seconds, the engine fires unstable, closed to stopping. It also spits > black smoke out the exhaust pipe. After beeing warmed up, it seems to > work fine. I had the exact same problem when I bought my '89 YJ with the 258 6 cylinder engine three months ago. When I first started the engine when it was cold it wouldn't fast idle until it warmed up a bit. It was barely able to keep running at 500 rpm when cold. If I pressed on the accelerator the engine loped and misfired. The whole vehicle body shook. Black smoke came out of the tail pipe. Once it warmed up, everything ran perfectly. It was just a simple carb adjustment to fix it. I found this out after several failed attempts at getting a Jeep dealership to fix it. Specifically, the choke pull-back on the butterfly valve was set incorrectly. When you press on the accelerator before starting the engine up, the butterfly valve closes all the way, however, immediately after starting, it is supposed to open up (pull back) a tiny little bit. It wasn't opening up wide enough. Here's how you make the adjustment. I have a Carter BBD carburetor (model 8384, I believe) which has a small wire connecor on the choke which you bend to increase the pull-back. If you have a different carburetor, the measurement setting below might be different from mine. Check with a manual. First thing in the morning, when the engine is totally cold, take the air cleaner cover off, get a short piece of vacuum hose, remove the vacuum hose attached to the end of the choke, and put your vacuum hose in its place. Press on the accelerator to activate the choke and close the butterfly valve on top of the carburetor. Once the valve is closed, suck on the open end of *your* vacuum hose. Once you suck hard enough, you'll see the butterfly valve open just a little bit. You'll need some sort of gapping gage to measure the clearance between the the butterfly valve and the front of the carburetor wall (air horn). On my Jeep, the setting is .140 inches. Assuming you have the same carburetor, you may find that your setting is less than that. Bend the choke connector wire until you get enough clearance. Replace the carburetor vacuum hose and start the engine. It should be running smoothly. Peter Dusek >I'm new to the Jeep list and also new to owning a Jeep. I just bought a >used '89 Jeep YJ (Wrangler) with the 258cc 6cyl engine. It's having >problems, though, with cold idling. When you start it first thing in the >morning, the fast idle doesn't kick in till after a few minutes of >driving... and then it doesn't want to stop for quite a long time. I've >driven all the way to work (12 miles, 20 minutes) and it was still idling >at 1600rpm. Also, during the first few minutes of idling (before the fast >idle starts), the engine is loping along at 500-1000rpm so badly that the >whole body starts to shake. It also has a tendency, when driving it for >the first few minutes to die if you stop at stop sign and let the RPM's >drop. > >The local Jeep dealership spray cleaned the carb >and did some adjustments, but this did nothing. >Now they're suggesting a partial or full cab >rebuild. Should I go through with this or should >I just get anentirely new carburetor? I read >in the Jeep Owner's Bible that when it comes >time to rebuild the carburetor, you usually can >never get it back to like-new status, and >that it's usually better just to get a new one. >Is this a better idea? If so, should I get the >stock Jeep carburetor or something like the >Holley 2300 carburetor, which the Jeep Owner's >Bible suggests is a good replacement. The engine is stock, by the way. Pete, 258's are known for rough idling, especially when cold. If your fast idle isn't working when it is supposed to then the linkage settings are off. The best way to check whats going on is to take a look. As long as you don't have any electronic gizmoes on the carb, the fast idle operation is simple. Actually its operation is related to the auto choke. When you first pump the accelerator for a cold start-up you actually do three things: 1) Drop the choke plate from the wide open position (sticking up) 2) Pump a small spurt of fuel into the carb throat. 3) Set the fast idle cam on fastest idle. If you remove your air cleaner and turn the throttle plates by hand you can see all this happen (if its set right) Then, when you start the engine, heat goes through this little tube and makes the auto choke begin to open the choke plate. Building vacuum pressure also aids this I think. As the choke plate opens, it will allow the fast idle cam to rotate to a slower idle setting. However, the engine will not stop idling fast until you slightly depress the accelerator (or turn the throttle plates). Eventually, when the engine is all warmed up, the choke will open completely and allow the fast idle cam to drop out of the way letting the engine run normally. The best thing you can do is check out these linkages first. If the dealer won't give you any satisfaction take it to a small garage somewhere. Tell them your fast idle cam isn't working right and they can check for any linkage problems. But, before you spend any money, start the engine with the air cleaner removed so you can see if the choke is working or not. A new auto choke spring only costs about $3 and could be causing all this trouble. - David M. DeChristopher ------------------------------ You might try cleaning out the little heat tube that goes between the auto choke housing and the exhaust manifold. I soaked mine in carb-cleaner and a pile of carbon ran out. If this tube is clogged, your choke won't get any heat and won't open when the engine warms up. - Rick Viana ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Runs & Sputters After Turning Off When i shut off the engine it still stutters and runs a bit. It's an '88 wrangler 4,2 Ltr. carburated. THE ANSWERS: I've had this problem with a number of different vehicle (not my Jeep but it's a 94, so....) The cheapest things to try are (next time you fill up your gas tank) add a bottle of Gumout Carberator cleaner in with a new tank of good quality gas, make sure your air filter is reasonably clean and (if you haven't done so in the past 20,000 miles) replace your PCV Valve. Any of these very cheap things could solve the problem. at worst you've spent under $20 bucks, fixed most of the easy, obvious things and done no harm in the process. If it's only sputtering a little, this may well fix it. (The Gumout was a miracle for one of my cars. I had to do this every 10000 miles, but it was MUCH cheaper then replacing the carb.) Becki ------------------------------ Mine will only do that if I shut it off before it comes off the fast idle cam (extremely short trips). That's not a good thing to do anyway (lots of wear and tear, esp. on the exhaust) but sometimes you gotta move it out of the garage to get the ATV out... 8^) ! You may be running too high of an idle. That would do it also. Either case leaves a rich fuel mixture hanging around when you turn off the key. The engine will try to burn that like a diesel. Easiest way to ballpark the idle is to read your sticker under the hood, follow the setup directions, and look at the tach in the cab. Andy ------------------------------ Keep this in mind: this is caused by additional fuel/air being sucked in to the engine after spark is turned off, ignited by compression, or hot combustion chamber. I'd assume *nothing* is correct, and examine all aspects of the ingnition/fuel systems. If anything is set to other than factory settings (ie: tuned by "ear") it's usually hiding another problem. Check timing ... (does it "ping?") Improper setting could cause carbon build up in combustion chambers, which can ignite fuel after the ignition is turned off. Throttle plate set too wide at idle ... possibly in order to compensate for something else like a vacuum, timing, or intake manifold leaks. (See previous posts) -jm ------------------------------ If your engine can get some air through the carburetor after you shut it off then it would diesel as long as the carburetor can supply the fuel. Make sure your idle speed is not too high. High idle will definitely cause this problem. I had the same problem with my 85 Cherokee (2.8L-V6) and I was having problems with high idle and dieseling. I my case it was a worn throttle plate that would not close down the air passage at idle. Once I replaced it both problems disappeared. I don't know if you have anti-dieseling s olenoid on your carburetor. If you do, then it should cut off the fuel as soon as you turn off the ignition. Siamak Navid ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ FREQUENTLY ASKED QUESTIONS ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ What is an MIT kit? Essentially, an MIT shortens the over all length of the NP231 Transfer case (used by all YJs) by around 4 inches. This is important to anyone who installs a lift (except for body lifts) of 3" or more because it allows you to use a longer drvieshaft. A longer driveshaft helps avoid the steep driveshaft angles inherent in a tall lift. Of course this also necessitates that you get a new two-piece driveshaft made which fits your rig. An added benefit of the kit is that it allows you to remove the rear driveshaft without the tranfer case fluid leaking out (as would happen with a stock NP231 transfer case). This is an important feature in that it allows you to limp home in front-wheel drive if your rear drivetrain is damaged but still capable of coasting. Installation On the STHM Banana Rating [tm] scale, this would rate a 2.5 - 3.0 in difficulty. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ What is articulation? According to my handy-dandy dictionary, the closest definition, "a fixed or movable joint between bones," isn't very accurate and I suspect that offroaders have been mis-using the term. What they're referring to is the flexibility of a Jeep's suspension. Flexibility allows the wheels to move independently of each other, thus increasing their ability to follow the contours of the ground, where they can get traction. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ What modifications are required before I use my YJ offroad? The short answer is: none. But let me qualify this statement and then I'll go off on a tangent... If you're only going to be driving on gravel roads or snow-covered roads, the stock YJ is fine and needn't be modified one iota. However, if you're going to be taking your Jeep onto dirt roads and trails which are in poor condition, some modifications will be in order. I'll present them in order of importance IMNSHO: 1. Swaybar Disconnects YJs were designed, in part, to minimize the threat of roll-overs which were being experienced by boneheads who figured that a CJ could be driven like a sports car. It is these brilliant individuals to whom we can thank for the infamous swaybars mounted on all YJs. The swaybar is a steel rod which sits roughly ahead and above the front axle. It runs parallel to the axle and at its curved ends; it connects to the axle via two swaybar links. When you drive around a right hand corner, the Jeep leans to the left. This lean is characterized by the left side of the axle moving up, relative to the frame, and the right side of the axle moving down, relative to the frame. What the swaybar does is minimize the lean by preventing the axle lends from differing so much in their position relative to the frame. The left side of prevented from going too far up because it's connected to the right side, which is prevented from going too far down for the same reason. Both ends up or both ends down is not a problem because that's not characteristic of a lean. . The swaybar does its job and makes it safer to fast cornering but it severely hinders the YJ's offroad abilities. At the first patch of uneven ground or diagonal ditch crossing (which are very common here in BC), you will notice that your YJ ends up lifting at least one of its wheels in the air because the swaybar is forcing it to keep all its wheels level. While it may look cool, this makes it pretty difficult to tackle any trail which is too tough for the average AWD minivan. Since you didn't buy a YJ because you had dreams of running with minivans offroad, you'll want to modify the swaybar in such a way as to make it easy to disconnect it for offroad use. All the methods involve disconnecting the swaybar by either removing or partially disconnecting the link between the swarbar and the axle. The cheapest method is to remove the bottom nut and disconnect the bottom part of the links from the axle. Once disconnected, you can fold the links and swaybar out of the way by using bungee cords or zip ties. The downside to this method is that it's rough on the link's bushings and can be very difficult because of the tight fit. However, some guys swear by this method. The next expensive method is to buy a set of Slickrock diconnects which are, essentially, bolts which replace the bizarro OEM bolts at the top of the links. With these in place, you can remove the entire link whenever you want, because the top can be unbolted. Cost for these is around $50USD per pair. The most expensive and convenient method is a set of JKS disconnects which replace your current link with a two-piece unit which separates by simply removing a pin. Bottom Nut Slickrock JKS Ease-of-use WORST OK BEST Cost BEST OK WORST Price FREE $50USD $75USD 2. Bigger Tires Now tht you have done something to keep all four tires on the ground, you should make sure you've got aggressive tires which provide good traction. The most popular offroading tire seems to be the BFG M/Ts. I'd recommend a 31" tire to start with. Besides better traction, larger tires also provide more ground clearance under the entire vehicle. Be forewarned, however, that once you get into the realm of 33" and taller tires, you MUST get your differentials' ring and pinions changed to bring your overall gearing back into a manageable range. Also, tires in this range are more likely to cause damage to your drive train if you are heavy on the throttle or have lockers in your diffs. Once you've decided to get bigger tires, you'll have to find a way to make room for them under your fenders. The next section presents you with the most popular options. 3a. Body Lift A body lift isn't any more important than a suspension lift, but it is cheaper so I mention it first. A body lift essentially consists of adding spacers between the vehicle's body and the frame. The goal is to raise the body to provide more room under the fenders for the bigger tires (see #2). Here are the pros and cons: Pros - Cheap. - Doesn't raise the center of gravity as much as an equivalent suspension lift would. - Driveshaft angles aren't affected. - Stock springs are kept so the ride continues to be factory soft. Cons - Body lifts over 2" tall can put too much stress on the body's sheet metal, resulting in metal fatigue and torn metal. - They provide no direct increase in ground clearance. 3b. Suspension Lift This is the more expensive method of making room for bigger tires because suspension kits come with lots of parts. First off, there's the replacement springs or, in some kits, single add-a-leafs which are inserted into your existing spring packs. Then there's the longer shocks, brake line extensions or relocators, panhard bracket extensions, and if you've got a 3" or higher lift, a dropped pitman arm (for the steering). Oh, you'll also get some spacers which allow to you lower the transfer case an inch or so. This is required so that the angle of the driveshaft isn't too severe, otherwise your Jeep will suffer from excessive driveshaft vibration and u-joint failure. And finally, the kit should also have some brackets which either lower the bumpstops or prevent the axle from hitting them. This is required because the kit's makers assume you want a suspension lift to install bigger tires. If you install bigger tires, during full suspension compression, they _will_ hit the fenders because their radius is greater than the stock tires. Pros - Directly provides greater ground clearance for the undercarriage but not the axles. - Provides more suspension travel and articulation. This means it can do a better job of keeping all four tires on the ground, a Good Thing [tm]. - If you buy a stiffer set of springs, they should be strong enough to support the added weight of all the heavy-duty goodies you're going to be carrying on your Jeep (eg: a winch). Cons - Expensive...kits start at around $600USD. - Stiffer ride unless you buy "soft" springs but the retailers I've talked to say they sag sooner. On the other hand, I've heard some positive results from owners of "soft" springs so your mileage may vary. - The higher you go, the greater the angle of your driveshaft. This equals more wear and tear on the u-joints. 3c. The Spring-Over-Axle Conversion This is the least common but probably most desired method for making room for bigger tires. As of yet, there are no kits which allow you to avoid the fabrication process which requires that you weld new spring perches on top of your axle tubes. The lift which is a function of the axle tube diameter and spring pack thickness will be around 4" - 5". You will still require the same pieces as the Suspension Lift such as brake line extenders, etc. Pros - Lots of lift while maintaining the original soft, factory springs. Cons - Expensive...custom fabrication work costs money. - The higher you go, the greater the angle of your driveshaft. This equals more wear and tear on the u-joints. - Articulation remains the same because you're still using the stock springs which generally have less suspension travel than aftermarket springs. Of course, you _could_ perform a spring-over conversion on aftermarket springs, but then you'd have a very tall and probably impractical lift. - Some people have experienced axle wrap problems with this kind of modifiation. You might have to install a ladder bar or horizontally-mounted shocks to correct this problem. Again, this is custom work and will cost you either time or money. 3d. Shackle Lifts This is the least recommended (by me) method for gaining clearance for your tires. The lift is gained by using longer shackles instead of taller springs. Besides the shackles, you also need the same ancilliary equipment as the other suspension-modifying lifts such as longer shocks, etc. The biggest downside is that, for every inch of lift, the shackle has to be twice as long. For example, a 2" lift would require shackles which are 4" longer than stock. Now, if you install these shackles in order to utilize 31" tires which are, say, 3" taller than stock, this would give you 1.5" of lift due to the tires, but your front shackles would be 2.5" closer to the ground than stock (4" - 1.5" = 2.5"). What this means, in real world terms, is that you're going to end up smashing your front shackles into rocks because they're hanging down so low. Pros - Cheap; less than $100USD. - Easy to install. - Soft ride because you can use factory springs. Cons - The higher you go, the greater the angle of your driveshaft. This equals more wear and tear on the u-joints. - Very long front shackles will screw up the caster of the front axle. Would require shims to fix this. - Articulation remains the same because you're still using the stock springs which generally have less suspension travel than aftermarket springs. - Due to the greater leverage exerted on the shackles' bushings, they will wear quickly and handling will suffer. - Front shackles will be closer to the ground and drastically affect your approach angle. 4. Lockers or Limited Slip Differentials I've placed traction-aiding devices after suspension and tire modifications because a YJ with the above modifications is quite capable in the dirt and retains the majority of its original street manners. As soon as you install a locking differential in your vehicle's axle(s), its functional balance has crossed over from street-orientation to offroad-orientation. To a lesser extent, this also applies to limited slip differentials. How the differentials work: When cornering, the front wheels follow a wider arc than the rear wheels, and the outside wheels follow a wider arc than the inner wheels on the same axle. This discrepancy in the arcs means that when cornering, all the wheels travel at _different speeds_. Because of this, your Wrangler has two differentials which accomodate this requirement by allowing the wheels to turn at uneven rates. Front differential - allows the front outside wheel to turn faster than the front inside wheel. Rear differential - allows the rear outside wheel to turn faster than the rear inside wheel. This is all well and good on the pavement, because they allow all the wheels to turn smoothly around corners. One of the side effects of these "open" differentials is that they balance the torque between the two wheels (or the front and rear axles, in the case of a centre diff). In the case of a rear axle with one wheel on ice, that one wheel will have close to zero torque because it has nothing to work against (ie: traction). Consequently, the _other_ wheel will also have zero torque applied to it. You've probably noticed this before when you or someone else has been stuck and only one wheel on the axle was spinning while the other wheel was doing nothing. This problem can come up anywhere where one wheel is on a poor traction surface while the other isn't. What limited-slip and locking differentials attempt to do is to transfer torque to the wheel with the traction. It makes sense but it will also have some pavement-handling penalties, as we shall see later. Limited Slip Differentials Utilizing clutch packs and/or special gear sets, they operate as normal open differentials until one wheel starts to spin more than the other. Once this spin threshold is crossed, the LS shifts torque to the wheel which is spinning more slowly (or not at all). LS diffs are better for pavement driving because for the most part, they act like open differentials. Automatic Locking Differentials (Lockers) These units _do not_ act like open differentials at all because their default state is to lock both wheels together. Only when turning on surfaces with good traction (eg: pavement) will they allow the outside wheel to disengage and freewheel faster than the inside, driven wheel. Because their default state is fully locked-up, auto lockers are not recommended for YJs which will see moderate to extensive use on icy or snow-covered roads because they are _very_ prone to fish-tailing. Manual Locking Differentials (eg: ARBs) Operating pneumatically or electrically, these differentials can operate as open diffs until the driver presses a button which causes them to lock up. These units will _not_ allow the outside wheel to disengage around corners so they require the driver to be aware of where and when he should use them and where and when he should disengage them. Limited Slip Pros - Very tame highway manners. - Can be used on snow-covered and/or icy pavement. - If you buy a Jeep with a factory-equipped Trac-loc rear diff, you should get the 3.55 ring and pinion gears which are better than the 3.07s you'd get (applies to 4.0L, 5-speed models only). You could then toss the Trac-loc later on when you install a new rear diff. (Warning: check with your dealer to see if this is correct) Cons - Models which use clutch packs must have them changed every couple of years or so. - In most cases, the torque split isn't even so the wheel with traction may not get as much torque as it can handle. (eg: the spinning wheel may get %70 while the wheel with traction will only get %30). - Because the LS only transfers torque once one of the wheels loses traction, it means that the LS only starts to work _after_ you're experiencing a problem. In contrast, a locker always splits the torque so it could prevent you from getting into a traction-loss problem. Automatic Lockers Pros - Torque is split evenly between the wheels. Performance on offroad trails beats a limited slip hands down. - No clutch packs to wear out. Cons - Handling on icy roads can be hazardous to your health. You need to go slow and steady, perhaps more so than your average front wheel-drive car. - These units can be noisy when they disengage the outside wheel (especially the older Detroit Lockers). - Pavement handling can be skittish until you get used to the locker's characteristics. Your Jeep will not like being accelerated around corners and will let you know by way of pronounced understeer and oversteer, depending on your throttle position. Chirping of tires around tight corners will also happen unless you use a light throttle foot. - Tires will wear more quickly, although the degree of wear varies with the driver, the tires and the air pressure. Manual Lockers Pros - Torque is split evenly between the wheels. Performance on offroad trails beats a limited s lip hands down. - No clutch packs to wear out. - Very tame highway manners (just like stock!). - Can be used on snow-covered and/or icy pavement. Cons - VERY EXPENSIVE. - In the case of ARB Air Lockers (your only option for YJs): - The majority of problems are related to a poor installation so make sure you get it done by a reputable shop which is very experienced in these matters. - Air lines tend to melt or tear. Keep this in mind when routing the lines and always bring spares. - Relays aren't particularly reliable to replace with some heavy-duty units and bring spares. - Stock YJ axles have been know to snap when the front end is locked-up while traversing good traction surfaces like rock faces. (This may-or-may-not be a problem for you...the onus is on you, the driver, to use the front locker only when you absolutely must and when it's safe to do so (eg: on loose dirt). By the way, this talk about differentials and lockers brings up something that novice Jeepers may not know: Full-time four-wheel-drive vehicles have a center differential which allows the front wheels to turn faster than the rear wheels (same principle as an axle differential). They _need_ this differential because if they didn't have it, their drive train would experience tremendous stress every time they went around a corner. But, offroad, it's possible for them to get stuck if only ONE tire loses traction. Why? Because if the one wheel on one axle loses traction, and therefore torque, then the other wheel does as well. And if that entire axle loses torque, then the center diff will balance the torque to the front by giving it zero as well. It is for that reason that they need a locking center differential. In comparison, your YJ (and just about all the older 4x4s) has no center differential. When you go into four-wheel-drive, it locks the front and rear axles together with no allowance for torque sensing. So, if some smarmy full-time four-wheel-drive owner tells you that he has a "locking center differential," calmly inform him that he _needs_ it in order to bring his 4x4 system up to par with yours for offroad use <g>. And here's a very detailed comparison provided by Willem-Jan Markerink: Steve Marton and Morgan Canfield asked some opinions/background on traction adding devices Almost a year ago I clogged up this list with several 'hungry' questions about these things myself, so I feel a little obligated to share the knowledge filtered from all the answers I got then, and some other info I tracked down since. Some of it is probably in the FAQ, but not all. Note 1: although I can now distinct the different types quite clearly, together with their (claimed) pro's and con's: I don't have a clear view on all solutions for one specific axle/diff. This question is best addressed to (members on) this list. I've only some specific knowledge on TLC 60 and 80 solutions. Note 2: feel free to react, and please send corrections if neccessary. Compliments are also welcome, as are funny remarks. Maybe it is even good enough to be (included in) a FAQ. In general, there are five ways by which a traction adding device (TAD) can function. By: 1) Speed sensing (SSTAD) (teeth, viscous fluid, brakes & wheel sensors) 2) Torque sensing (TSTAD) 3) By friction (FTAD) 4) By manual operation (cable, air, solenoid/electromotor) (MTAD) 5) By welding axles together (spool) [All abbreviations hereby copywrighted if not stated otherwise and/or claimed by other persons] Not all TAD's are one or the other, some are mixed. I have tried to classify the various brands/implementiations and names (AFAIK): 1a) 'Teeth' SSTAD: Lock-Right, Sof(t?)-Locker, EZ-Locker, 1b) Viscous SSTAD: Visco-Lok and other viscous fluid units 1c) Electronical SSTAD: Range Rover 4.6 (rear axle only), new Mercedes AAV 2) TorSen, TrueTrac, Quaife (also partly #3), Powr-Trak, Eaton Gov-lock (sp?, type?) 3) Various OEM LSD's, Auburn (Pro) 4) Various OEM diff locks, ARB, C(ommand) Locker 5) Not sure if they are available beyond DIY. So, how do they work? 1a) Basically, on a straight track it functions like a spool. However, in corners, a wheel is allowed to run *faster* than the ring gear (outside wheel free), but never *slower* than the ring gear (inside wheel driven). When the inside wheel slips, the outside wheel would go slower than the ring gear, so the grip wheel is locked to the slip wheel. You can compare its function by a 'single-direction coupling', with the that a mechanical TAD will operate in both directions, its function whenever torque reverses (I assume). 1b) Two sets of multiple plates are connected to each other by a viscous fluid. They allow a certain amount of rpm difference without significant 'binding'. When slip occurs, the viscous fluid gets warmer and thicker, and it will finally lock up till its maximum setting. 1c) Whenever slip is sensed by wheel sensors (requires ABS), the brake on the other wheel is engaged. This simulates grip-torque, and with an (still) open diff this means the other wheel receives an equal amount of torque. 2) Torque sensing TAD's are IMO the most difficult ones, and likewise complicated to explain. I have a whole bunch of formulas from TorSen, in which its principle is described. Basically, it uses a set of gears inside the diff carrier, that act like a worm and roll, the worm can drive the roll, but the roll cannot drive the worm. Suppose you have a torque of 7000Nm available on the carrier of a TorSen diff. With only 1000Nm grip available on one wheel, the diff biases 6000Nm to the other wheel (1:6; for ease of reasoning assuming that this other wheel has enough grip to 'accept' this amount of torque without slip). With an open diff in the same sitation you would have only 2000Nm grip (1000Nm on each wheel), with a TorSen 7000Nm (1000Nm on one, 6000Nm on the other wheel). For a better understanding, I always try to imagine it as allowing speed differences between axles caused only by torque coming *from* the outside, not going to the outside. It is then multiplied and send to the other axle. The Quaife is basically a TrueTrac/Powr-Trac, but adds another element, friction, by which it also functions when one wheel is airborn. It functions like a lower limit of torque transfer. 3) The friction TAD has a sort of clutch inside the diff, by which both wheels are always connected to some extend. It will 'bind' the wheels together with just a specified, constant amount of torque (disregarding wear). Therefore there is always a certain amount of send to the least-grip wheel, even when this wheel is . 4) Manual TAD's lock by engaging a sleeve that connects both axles together, either by cable (Toyota OEM), air valve (ARB) or an solenoid (electromotor??) (C-locker). More precise: one of the axles is connected to the diff carrier, thereby connecting the other axle by gears as well. 5) It's just that, welding, disallowing the entire diff inside gear train to rotate. [Note: some people claim that this can also be done by welding repair on an axle, while grounding the drive shaft <grin>] Pro's/Con's 1a) Mechanical SSTAD's (teeth) lock 100% when slip occurs. Older types did this quite aggressively, thereby causing difficult slip handling in slippery corners. Sudden changes in torque (sudden engine braking and accelerating) were also nasty, especially in corners. In corners, they send torque to the inside wheel only, thereby increasing the possibility of slip. Later versions (Sof(t?)-Locker) are claimed to be much more friendly in handling. ABS is not possible (I guess, any experiences?). 1b) Viscous SSTAD's will lock till their maximum setting when slip occurs (maximum variable depending on design, like number of plates, size of plates and fluid characteristic). They still work when one wheel is ariborn, but they also allow some speed difference at all times. Current design is claimed to need several seconds to lock up completely. Future units (Visco-Lok, OEM unit in '98 for at least two US manufacturers) claim to lock up within fractions of a second. ABS is possible. 1c) Electronical SSTAD: brake pads and disks will wear faster. This version is therefore only seen on 4x4's that hardly see difficult stuff. Requires wheel sensors, and therefore ABS is obligatory. 2) Torque sensing TAD's 'bind' *before* slip occurs, not afterwards as all other automatic versions do. The grip difference can be up to 1:2.5-3 (TrueTrac) or 1:6 (TorSen) before one wheel finally starts to spin. They are claimed to have a narrow area of handling at the grip limit. Normally, you can rely on an inside wheel-spin only, still having the outside wheel for lateral grip. The chance that both wheels start to spin at the same time is larger. With one wheel airborn, slip-torque = 0, so even a muliplication by 3 or 6 will equal a grip-torque of 0. You are stuck. However, by applying the brakes you can simulate a slip-torque larger than 0, thereby sending a multiplied torque to the grip wheel, which in turn is larger than the brake torque on that side. You probably can free yourself. (AFAIK, this procedure is also stated in the Hummers manual, and mentioned several times in articles about other TorSen-equipped trucks) A Quaife diff adds a lower limit of torque transfer to the TrueTrac principle. But although this friction is multiplied by its gears and also works with one wheel airborn, you still can get stuck, like you could with a friction TAD, only later. It also wears out, but if it ever does completely, you would still have a TrueTrac. These types of diff's allows proper steering when mounted in the front axle. ABS is possible. 3) They are cheap, wear out and require special LSD oil (all??). They also have a limited amount of friction torque (anyone torque numbers on this one?). On the other hand, they also 'bind' at all times, even in near-0 grip situations on ice. These two factors equal a stuck-in-the-middle dillema: not enough friction, and they are useless; too much friction, and they will induce slip. However, they have predictable handling characteristics. And with one wheel airborn, it will still send some torque to the grip wheel. Not sure whether ABS will work properly (any experiences?); probably yes. 4) The only one that allows you full control. You can choose for the predictability, handling and steering of an open diff, and the ultimate lock of a spool. Front lock will result in a turning radius of infinity, unless one wheel is airborn. Aftermarket installation requires some extra wiring; either airlines (ARB) and an compressor, or electrical wires (C-Locker), the first with the most added complexity and chance of malfunctioning (Murphy). ABS is possible, but it should be turned off whenever one or both axles are locked. Some factory axle locks (Toyota 80 after '92) will only work after engaging 4low (= center diff lock), by which ABS is automatically shut off. MB Gelaendewagens have a separate ABS shut-off button, and an automatical shut-off whenever one of the three diff's is engaged. 5) The inventor of the open diff will probably turn in its coffin, but hey, it works! Tires will wear faster, cornering on sticky surfaces is problematic, risk of breaking axles. In the parking lot of the mall, everyone will think you are nuts and can't drive. However, many of these spools will never see normal roads. A spool in front will equal a turning radius of infinity, unless one wheel is airborn. ABS and spool are mutually exclusive. (anyone ever tried, or even had a truck new enough to have ABS?) ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ What the heck is a YJ? That's the Canadian model name for the Jeep Wrangler. Why the difference? Because GM was already using "Wrangler" as the model name for one of their full-size pickups. Hence, I will use "YJ" and "Wrangler" interchangably. Follow us on Twitter at www.twitter.com/OffRoadDotCom
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Posted Aug 02 2008 03:22PM
