YJ front & rear axle misaligned after2.5" susp lift

[ranmoo58]

Just put a 2.5" susp lift on my yj and installed 33" x 12.5 tires. After putting on the new tires I noticed that the rear axle is about 2-3" out of alignment, towards the passenger side and the leafs look like they are tilted slightly to the passenger side. The front leaf springs also look like they are tilted out of position, same as the rear, toward the passenger side. It seems to drive straight, but the rear axle isnt in line as it should be, causing vibration at different speeds and gears.

All of the alignment pins are properly seated and there isnt enough slack in the u-bolts over the axle to make up the difference in distance. The frame doesn't appear to be twisted or bent, but I had a really hard time lining everything up, but everything was loose fit, placed on the ground, then tightened. The rear (both sides) was done first, then the front.

The friend that helped do the lift has done several on Jeeps before this one, he said he has never had any problems and this was, by far, the toughest hes ever done.

Any suggestions would be greatly appreciated, hopefully before I start eatin' universals by the truck load.

 

[Bounty__Hunter]

The track bars (panhard bars) on the axles will cause the axle to be off - center after a lift if you don't use relocation brackets. The track bars are the bars parallel with and on top of the axle tubes, connecting the axle to the frame. Get rid of the rear, you don't need it. Many YJ owners get rid of the front also, me included.

The axle being off - center won't cause a driveline vibration as much as the wrong pinion angle will. You want the rear axle pinion to be parallel to the transfer case output, thus making both rear u joints operate at the same angle to cancel vibes.

2.5" lift isn't enough room for 33" on a YJ without more mods like fender trimming. The rear tires will hit the fenders bad when the axle articulates or you have rear passengers.

 

[carnuck]

If there is no trac bar, maybe a leaf set was installed backwards?

 

[ranmoo58]

I see why the track bars are a problem. I have two concerns, 1st. now that the lift is installed, I dont really see how I can remove them without taking everything back apart, if I jack it up and support the frame, it looks like theres a lot of pressure from the springs and the bolts are hard to get to and frozen in place like everything else. I thought about cutting the bolts off, but still concerned about where that bar is going to go when it pops loose. 2nd, without the track bars, wouldnt that drastically affect how it handles at highway speeds and cornering, or should the springs be stiff enough without swaying.

I double checked the pinion angle and the position of the shim wedges on the new springs for the rear. Springs are installed with the thick part of the shim point toward the front of the vehicle per the installation instructions that came with the kit.

I stopped by a frame/suspension shop today to see if they could offer any suggestions or if they would remove the bars (safely) for me. They suggested installing relocation brackets front and rear, quoted me 4 hrs of labor/material, came out to $275. They also mentioned that I would most likely have driveability issues by removing the track bars altogether. Not sure if this was their way of pushing the relocation bracket work or not.

This is my first Jeep, so I'm fairly new to the jeep culture, especially the support network out there, but the more I work on this thing the more I understand how much fun it can be. I should have mentioned that this YJ is my daily driver, mostly freeway and residential, never even considered anything off road (Hmmmm). The price was right when we picked it up and have been making repairs and improvements as cash flow permits.

Special thanks to anyone that provides feedback, very much appreciated. I will take the advice of fellow Jeepers any day, rather than from a shop guy thats working on commission.

 

[Bounty__Hunter]

You will not notice a difference in handling after removing the rear track bar. It's pretty pointless as the rear axle tracks well behind the solid spring hangers on the frame.

Many remove the front track bar with no ill effects. You would just have to try it and see. The front axle tracks behind the shackles so the shackles can allow some side to side movement of the front axle. The steering also inputs side forces on the axle. I haven't run either front or rear track bars for years, and I'm running about 7" of lift.

Cut the track bar bolts with the Jeep on the ground, weight on the suspension. If possible.

 

[ranmoo58]

Gives me an idea, I'm scheduled to have a shop install relocation brackets, I'll have them disconnect the bars and go for a ride. If it feels wonky, I'll have them install the brackets, if its OK, a 4 hour job turns into a 2 hour job and will only cost me half as much.

This should let the suspension square up with the rest of the frame, it'll be nice to get the drive line back where it should.

good input BH, thx

 

[Bounty__Hunter]

If you don't like how it drives, install the front track bar only and take it for another drive. Chances are you won't notice a difference with the rear track bar gone.

 

[jps4jeep]

Jeep YJ = No trac bars. You do not need them.

 

[ranmoo58]

Too late, bit the bullet and had relocation brackets installed front and back, before I got other comments about leaving them out.
I did drive it without either bar hooked up, was a little too floaty to me, So I had 'em finish it. Drives super straight and I know what it feels like with a functional suspension again. Gonna replace the tie-rods ends this weekend, then align. I had to move the skid plate over 1" to get the shaft where it should be, but no vibration at any speed/gear.

Finally.

THX to all, much appreciated.

 

[jfrabat]

Just for your information, eventually, the front relocation bracket is prone to coming loose, so check it after a few thousand miles. In my YJ, I left the rear track bar off, and got me a JKS telescoping track bar for the front. This one you can disconnect when you go wheeling to allow for more suspension travel. I don't think it is as stiff as the stocker, but to be honest, I have driven quite far on it and don't have any issues...

By the way, judging from the first picture, you jeep either has a ton (or more like 4 tons) of grip, or it generates a LOT of downforce!