Step by Step - a detailed installation of theTomken Machine 4" TJ lift kit
by Don Alderrou

Table of Contents:

1. Introduction
2. Parts - Included in Kit, Packaging, Recommended
3. Tools - Required, Recommended
4. Installation - Rear, Front
5. Testing - Actual Lift, RTI Score, Handling, Driveability, Off-road performance
6. Conclusions

1) Introduction:

There are many TJ suspension lift manufacturers, but very few of them include both upper and lower control arms. On my Cherokee I had previously installed a Tomken 4" lift and was very satisfied with the workmanship and design of the kit. So, naturally, I contacted Tomken when doing the research for the TJ lift. Since it had been about two years since I did the XJ lift I found there have been many improvements in suspension technology during that time. Tomken has been integral in developing many of these innovations and is on the leading edge with their 4" TJ lift.

Two of these innovations are twisting/rotating control arms (Tomken calls them "Super-Articulating Control Arms") and three piece sway-bar disconnects. When the front anti-sway-bar is disconnected the amount of articulation is amazing. The rotating control arms reduce the stress on the frame/axle brackets and reduce a restriction that allows the axle to articulate even more. I have a friend with a similar lift which only has drop brackets for the stock lower control arms. Due to extreme flex on the trail, he eventually ripped the mounting bracket from the frame. After he re-welded the bracket he has upgraded to Tomken's control arms and has not had any problems since that time.

The first generation of quick-disconnects where two piece and used a single pin to attach the two pieces. Usually they are easy to disconnect and a major pain to re-connect. Also, the two pieces would scrape each-other and other parts when the axle articulated. Now, many manufacturers sell three piece disconnects where two pins hold in a center section. This solves the scraping problem, but it can still be difficult to re-connect. Tomken solves both problems with their new two piece "wingnut" design. There is a pin on the bottom to allow the removal of the entire link. The wingnut on the top provides an adjustment which makes it easy to re-connect. Tomken also provides a convenient storage bag to hold the two links and a retainer to keep the sway-bar out of the way.

2) Parts:

2.1) Parts Included in Kit

The following parts are included in the complete lift kit and may also be purchased separately:

2 Front coil springs.
2 Rear coil springs.
4 Super-Articulating lower control arms with new bushings.
2 Front upper control arms with new bushings.
2 Rear upper control arms with new bushings.
2 3" Front bump stops.
2 3" Rear bump stops.
Sway-bar disconnects with storage bag and retainer.
Rear trak-bar relocation bracket.
Parking brake relocation bracket.
Transfer case drop (1 5/8")

The Pro-Comp ES3000 shocks are not included with the TJ lift,
but they are available from Tomken:

2 Front shocks part # 324515.
2 Rear shocks part # 324509.

2.2) Packaging

The kit arrived promptly in 4 boxes. One box for the shocks. Two boxes for the springs and control arms. One box for the brackets, sway-bar disconnects, bump stops, and transfer case drop. The two boxes with the springs and control arms were not packaged very well. The parts had shifted during shipping and some of the paint was chipped. Some of this could have been caused by rough handling because of the UPS strike, but the parts would have been better protected with a foam wrapping or bubble-wrap instead of newspaper. Also, the paint that Tomken uses could be improved upon (They have since switched paint systems - ed.). I had my parts powder-coated before installation.

2.3) Additional Recommended Parts

New front brake hose: This is probably not really needed. Since I'm a little paranoid about the front brake hose, I knew this would make the TJ bullet-proof, and it does not cost much, it seems like a good thing to do. The YJ (87-95 Wrangler) brake hose are three inches longer than the XJ/TJ/ZJ hoses while keeping the same mounting points. I picked them up from the dealer. They were in stock and cost about $24 each. Tomken's kit says to re-locate the upper connection by drilling a new mounting hole and bending the ridged line. This may get an extra two inches in length. One of the other kits has"one inch re-locating brackets" that fit into the stock mounting hole, but you still have to bend the rigid line. Both of these place the upper connection of the brake hose lower on the frame rail where it is more susceptible to damage. Also, don't forget to buy new washers for the caliper connection of the brake hose. A total of four washers are needed, two for each side. For the Cherokee write up on the brake hoses, See:
http://www.off-road.com/jeep/cherokee/brkline.htm

Comparison of brakelines	Before bend	After bend
Dealer part numbers: 52008778, 52006473, j3237672. Part store numbers: XJ/ZJ/TJ = sp8656/sp8657 YJ = sp8659/sp8660

3) Tools

4) Installation

The instructions from Tomken came as two stapled sets of 8 1/2" by 11" sheets on standard paper. One set has the diagrams and is seven pages long. The other set has the step-by-step instructions which reference the diagrams and is four pages long. There is a note at the top of the instruction page "Please read all the instructions and diagrams before you begin".

Before I started, I unpacked all the parts and read through all the instructions. I'm glad I did this because there were some questions which were not covered in the instructions. Tomken is not open on the weekend and if I started and had questions half way through, I would not have had the answers and not been able to finish. It took the entire weekend for me (and a helper - thanks Rick) to complete the install. It will not take as long if you have air tools and are not taking pictures and notes.

The instructions don't say which end to do first. The order has the front listed first, but I decided to do the rear first. I don't think it matters and it is a little easier to drive if the back is higher than the front. Once the rear was done I drove the TJ to turn it around.

This is my step-by-step guide to installing the lift:

4.1) Rear

The rear Preparation steps are:

1. Chock/block the front tires from rolling.
2. Jack up rear and place jack stands in front of the control arm mounts. I placed the jack under the axle so the jack stands were about 20" high.
3. Lower until frame touches jack stands.
4. Remove the tires. 3/4" lug wrench.
5. Since I already removed the rear stabilizer (sway-bar,) I did not need to remove the lower link bolts.
6. Disconnect the rear drive shaft from the yoke at the axle. 8mm socket. Use some string to secure it out of the way. I tied it to the exhaust pipe. This will prevent accidentally pulling the slip-yoke apart when moving the axle around to install the new springs. I did this once long ago.
7. Remove the track bar. 18mm socket, 15mm socket, T55 torx.Note the position of the bend at the frame mount.
8. Remove the shocks. 18mm socket, 15mm socket, 1/2" socket.
9. Remove the parking brake cables (left and right) from the bracket. 13mm wrench. The adjuster (equalizer nut) must be backed-off almost to the end to install the relocation bracket. Once it was far enough to remove the cable, I removed the equalizer and put it in the bench vice to finish backing the nut out. It is much easier than using pliers/vice-grip and laying on your back. To remove the cable ends from the bracket, I used a small hose clamp to compress the fingers which hold the end of the cable to the bracket.
10. Remove the parking brake cable brackets and wiring bracket from the upper control arms. 1/2" socket. Note the location of the bracket on the upper control arms.
11. Loosen the bolts for the upper and lower control arms. If you remove the upper arms it is hard to remove the lower control arm bolts at the axle.
12. This is a good time to put both jacks under the axle. I placed one on each shock mount so there was enough room to remove (and install) the lower control arm bolts. Also make sure to support the axle at the pinion so it does not rotate.
13. Lower the axle and remove the coil springs.
14. Remove the upper and lower control arms. Be careful when taking out the passenger side upper control arm bolt from the frame mount. The muffler heat shield is sharp. I bent it up towards the body after my first cut knuckle.

The rear Install steps are:

1. Install the bushings and steel sleeves in package 2007-x into the upper control arms. Use the supplied white grease to lube the bushings. Be sure to ration the white grease. There is not much supplied. I used the steel sleeve to "roll-out" all of the white grease from the packet. Since the lower arms have zerk fittings and can be re-greased, do the upper arms first. If you don't put on enough white grease, the bushings will get noisy. A bench vice makes the bushing/sleeve install much easier.
2. Install the bushings and sleeves in package 2008-x into the lower control arms.
3. I drilled the 3/8" hole for the bump stop extension in the lower spring pad. Use the smaller diameter bump stop for the rear and the larger for the front. Remember to measure twice and drill once. Mark the middle of the pad and use a punch/hole-starter to keep the alignment when starting. De-burr the new hole with a round file. It will make installing the nut and lock washer easier. Check the hole with the bump stop to make sure it inserts easily.
4. Install the track-bar relocation bracket. The bottom axle hole needs to be drilled out for the 7/16" bolt. I used a 7/16" drill bit and reamed it out a little to get the bolt to fit. I could not get a wrench on the lower nut, so I used a slotted screwdriver pressed against the bracket to hold it in place while turning the new bolt provided. Only do this after all the bolts are in place and started.The original bolt is for the track bar. The new bolt and spacer go into the original hole to hold the relocate bracket in place The spacer was too long (probably from the powder coating I had done) so I had to cut off about 1/4". Be careful not to cut off too much, the spacer should fit snug in the original bracket. Tomken provides two good diagrams showing how the bracket connects to the original.
5. Install the axle side of the track bar only. Leave the frame side loose. Remember to check the position to make sure the orientation is correct.
6. Install the upper control arms. I did this first to help control the axle when installing the springs. Note that the rear upper control arms are different. The drivers side has the parking brake bracket in the middle. The passenger side has it offset. The bracket should be on the lower inside edge of the arm. The passenger side is closer to the axle to keep the parking brake cable away from the exhaust. Do not torque the control arm bolts at this time.
7. Install the springs. I rested the bump stop inside the spring while installing the spring. This way I did not have to use a spring compressor to get the spring over the bump stop. Now put the bump stop in the pre-drilled hole and use fingers to hold the bump stop while tightening the nut. Installing the nut is a little tricky. I wedged the nut into an open end wrench with a piece of paper to get it started.
8. Install the lower control arms. Install the frame bolts first. Now the fun part. Use the jacks to align the lower control arm axle bolts. Once close, put a big screwdriver through both the bracket and control arm sleeve for the fine alignment.
9. Install the frame side track bar bolt.
10. Torque the upper control arm bolts to 55 ft-lbs. Torque the lower control arm bolts to 130 ft-lbs. Torque the track bar bolts to 74 ft-lbs.
11. Install the parking brake cable drop bracket and install the cables and equalizer. Remember to adjust the parking brake. Tomken provides two good diagrams showing how the bracket connects to the original.
12. Install the parking brake cables and wiring bracket to the new upper control arms.
13. Install the rear sway bar. (I did not do this).
14. Re-connect the drive shaft. Torque the strap bolts to 14 ft-lbs.
15. Install shocks. The Explorer rear shocks came with a crosspin which was too short. I used the bench vice to press out the crosspin from the original rear shocks. The lower mount point for the original shocks had a sleeve. The Explorer came with a sleeve, but it was too long. I used the hacksaw to trim the sleeve to the proper length.
16. Check brake cables and hoses at full drop.
17. Install tires. Torque wheel nuts to about 90 ft-lbs.
18. Remove jack stands and lower the Jeep.

The initial amount of rear lift was about 5.5" and the rear drive line angle was incredible. After ramping the TJ and driving around with some weight in the back, the amount of lift leveled out to 4" (5" including the extra inch for the 33" tires.)

Installing the transfer case drop spacers:

Support the transfer case skid plate (crossmember) with two jacks and remove the 6 bolts connecting it to the frame. Install the six 1 and 5/8" tall spacers between the frame and crossmember with the flat side of the spacer against the frame. Install the bolts with the lockwasher first and then the cone-shaped washer with the flat side of the cone-shaped washer next to the lockwasher.

4.2) Front

The front Preparation steps are:

1. Chock/block the rear tires from rolling.
2. Jack up front and place jack stands behind the control arm mounts. I placed the jack under the axle so the jack stands were about 20" high.
3. Lower until frame touches jack stands.
4. Remove the tires/wheels.
5. Removed the front stabilizer (sway-bar) links; This is much easier said than done. Use 18mm and T55 torx to remove the bottom bolt of the link. The top is a 15mm socket, but the pin is a press fit. I did not have a pickle fork and even if I did, I think it would still be tough. Once both sides were disconnected at the bottom I rotated the sway-bar forward and put an open-end wrench between the link and sway-bar instead of the pickle fork. With one helper holding the other side of the sway-bar against the bumper and me prying on the wrench, a second helper was hitting the link with a big hammer. After many hits on the side (yes, hit the link at 90 degrees to the direction you want it to go) and the top it came loose. It might have been easier to remove the entire sway-bar with the links and use the bench vice, but my custom bumper/winch mount stopped those plans.
6. Disconnect the front drive shaft from the yoke at the axle. 8mm socket. Use some string to secure it out of the way.
7. Remove the passenger side track bar bolt. T50 torx. Mine was mis-threaded and very hard to remove. I had to go to the dealer to buy a new bolt and retainer. Part numbers from the XJ are 34202640 and 34202463. They didn't have the TJ ones, but they had the XJ. They looked the same to me.
8. Remove the shocks. 5/8" top, 1/2" bottom.
9. Remove the brake line attaching screws located inside the front fender wells. T40 torx. This will allow the axle to move around more when installing the new springs.
10. This is a good time to put the two jacks under the axle.
11. Reference the positioning of the adjusting cam for the lower control arm bolts. I put some nail polish on the markings.
12. Loosen the upper and lower control arm bolts. The upper control are bolts have a retaining clip that would not catch. I used a vice-grip to hold it while removing the nut.
    
13. Lower front axle until springs are uncompressed and remove the spring retaining clamps. 13mm. Be careful to not stretch the brake lines too much when lowering the axle. My TJ did not have a spring retaining clamp on the passenger side, so I bought the retainer and the screw from the dealer. Part numbers 6502468 and 52005917. I would recommend doing this. When the TJ was on the ramp the front spring started unseating at the top.
14. Remove the springs.
15. Remove the upper control arms. 15mm socket.
16. Remove the front bolts from the lower control arms. 13/16" Be sure to remove the nut and hold the bolt head so you do not damage the alignment eccentric. The bolt is slotted and the eccentric washer fits in that slot so it moves with the bolt head.
17. Remove the rear bolts from the lower control arms and remove the entire arm.

The Front Install steps are:

1. Install the bushings and steel sleeves in package 2007-x into the upper control arms.
2. Install the bushings and sleeves in package 2008-x into the lower control arms.
3. I drilled the 3/8" hole for the bump stop extension in the bottom front spring pad. There is already an impression in the center of the pad to help start the holes. Check the hole with the bump stop to make sure it inserts easily.
4. Install the springs. I rested the bump stop inside the spring while installing the spring. This way I did not have to use a spring compressor to get the spring over the bump stop. Now put the bump stop in the pre-drilled hole and use fingers to hold the bump stop while tightening the nut. Installing the nut is easier than the rear. I used a socket and extension.
5. Install the new upper control arms. Do the rear bolts first and then move the axle around to align the front bolts. Do not tighten the bolts yet, just get them snug.
6. Install the new lower control arms. Do the rear bolts first and them move the axle around to align the front. The third jack really helps here because the axle may need to be rotated by jacking on the track-bar mount or under the pinion. Make sure to position the alignment eccentric in the same orientation it was when removed.
7. Lift the axle with the jacks to compress the springs. Make sure the springs are seated on the bottom properly and in their pockets. Lift the Jeep about 1/2" above the jack stands to put the entire weight on the springs. Attach the spring retainers.
8. Torque the upper control arm bolts to 55 ft-lbs. Torque the lower control arm bolts to 130 ft-lbs.
9. Install new shocks.
10. Install the new sway-bar disconnects. Do the lower bolt first, then rotate the sway-bar down onto the top and tighten the wingnuts.
11. Re-connect the drive shaft. Torque the strap bolts to 14 ft-lbs.
12. Re-connect the brake line bracket to the frame.
13. Install the wheels and lower the Jeep.
14. Now, with the weight of the Jeep on the tires, look at the side-to-side position of the axle. Keeping the side-to-side equal and using the diagram provided by Tomken, drill a new hole for the track bar on the axle mount. The instructions/diagram call for a new hole 3/4" towards the drivers side. My TJ only needed an extra 5/8" for the hole. If I went over more, the front axle would not have been centered. Any less, then there was not enough room and the new hole would run into the old. Also, you want to use the power steering to move the axle side-to-side and even drive the TJ around the block very slowly to help the springs settle and the axle to find the neutral position. Once the bolt is installed in the new hole, torque the trak bar bolt to 74 ft-lbs.

The alignment will be quite a bit off. I adjusted the toe and steering wheel position myself to get it close. Then after about two weeks of driving when everything settled, I re-torqued all the bolts and had it aligned professionally.

5) Testing

5.1) Height change

Initially the rear was over 5" higher and the front was only 3.75" higher with the same wheels/tires. This seemed strange at first because it is promoted as a 4" lift. After driving around some (about 2 weeks) the rear settled about one inch. This brought the front up since I measured from the bumpers and the change in the rear effected the front measurement. With the new 33" tires the change in both the front and rear is about 5" (4" from the lift and one inch from the tires.) I think this is pretty good since I have the 4.0L 6cyl engine and a 80+ lbs winch on the front.

5.2) RTI Score

The lift performed well on Accessories Plus RTI Ramp (20 degree). The Accessories Plus techs measured the score as 1060 without changing the tire pressure. (99" up with a 93.5" measured wheelbase. The owners manual also lists the stock wheelbase at 93.4", so the lift did not cause any changes).

Before the lift with the front sway-bar connected and the rear sway-bar removed, the TJ scored 690. (65" up with a 93.5" measured wheelbase).

Several people came out to look at it on the ramp and they seemed impressed by the lift. Both corners were on the bump stops and the other corners looked like the shocks were at full extension. If I got longer shocks it would probably do even better. The front corner that was on the bump stop still had two inches of shock travel left, so longer front shocks should be ok. The front spring started to come off of the top spring perch at full extension. The bump stop and retainer would not let it come completely out. One of the techs mentioned that some of the other TJ lift springs can be removed at full extension because their bump stop extensions are designed differently.

5.3) Handling, Driveability, Off-Road performance

On road it drives about the same as before. There were no problems with the shifting or engaging 4wd. I was worried about this because of the large transfer case drop - 1 5/8 inch compared to the standard one inch drop. With the sway-bar connected it has about the same amount of body-roll as before - not very much. The TJ is still a pleasure to drive.

There is no noticeable bump-steer after installing this lift. Many manufacturers suggest the use of a drop pitman arm on lifts of this height, but in this case it does not seem to be necessary. As long as the steering drag link (connects the pitman arm to the tie-rod or to the steering knuckle) is parallel with the panhard rod (track bar) no bump steer will occur. The new hole that is drilleed to relocate the trackbar end takes care of this issue and Tomken does not recommend a dropped pitman arm.

With the sway-bar disconnected the lifted TJ is now a true off-road machine. The amount of articulation is amazing and with the added 5" of ground clearance, there is not much that will stop it.

As with any lift/increase in tire size the gearing is an issue. Before the lift, the 31" tires and the 3.55:1 axle gears were a good match. Now after the lift with the 33" tires, the 3.55:1 gears are just OK. I'll probably have the gears changed to 4.10:1. to get back to the stock crawl ratio.

The new shocks are valved quite a bit stiffer than the stock shocks. They feel a bit too stiff for my tastes when driving on-road but are about right for off-road. I will probably take the part numbers and look-up the extended/collapsed lengths and then get some adjustable shocks which match. This is not a high priority now as the shocks provided by Tomken work reasonably well and while they are not as plush as I would like are not causing any problems.

6) Conclusions

The Tomken TJ lift was straightforward to install. The instructions and diagrams are clear and easy to follow. The kit provided the stated amount (4") of lift, and easily scored above the perfect 1000 RTI on a 20 degree ramp. The only place where I feel Tomken could improve is in the painting of their parts.

Overall, I am very satisfied with the Tomken TJ lift and recommend it to all who are looking for a competent off-road & on-road suspension.

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