Side to side driveline alignment

Hey guys,
I'm having driveline alignment issues from side to side from my tcase to the rear axle. I've got a 94 xj with iro 5.5 inch lift no tcase drop with a SYE and an 8.25 rear axle. I just changed the motor and transmission mounts and it's about 1-2 inches off from my rear axle yoke. The mounts are the shitty oem replacements. I just changed my u joints in the driveshaft and they're blown again only after a couple months. I've tried quite a bit to get them aligned but haven't had any luck. It's causing crazy vibrations even in 1st from a dead stop. Do you guys have any tips or tricks for it? Or can I get a link to another thread discussing how to fix this? Or is it a common problem that you just deal with by replacing the u joints sooner than normal?
I tried searching but didn't find much for a fix and I'm on my phone at work posting this so it's a PIA to use the search function anyways. Any info is appreciated.

It's possible to put the trans mount in backwards, take a look at this to see how the trans mount is offset:

travisk said:

Kastein, you were right. The transmission holes are in the same spot and the transmission mounts are paired with the different crossmembers so they line up the same. I took a picture.

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There's enough play in the bushings that you could have flipped the trans mount around when you installed it and still have gotten it back together. I'm not sure what else would cause things to be that far out of alignment.

I think I understand you somewhat. Beyond my DD.., I am not much into making many modifications such as what XJ owners on this side of the forum do, and thusly have way more comprehension, and/or desires to do so; for making their XJ's outstanding.

That said; You have indicated that your propeller shaft moves laterally off of mid-line. I had that same issue, and could be measured as being a couple of inches to the driver's side, and a couple of inches towards the passenger's side. With 220k, one week the shaft was fine, and then it was not, lol. Lucky I found the transmission mount problem before getting into a radical terrain situation, and trying to get out.

Since I have only a very minor lift, (just a bit up from the OEM factory set-up model.., 'Up Country' I think), I still had to double check my vertical angles with a mechanic's/carpenter's angle triangle, (type with a pointer), hence I had to use a T-Case drop brace for the specified vertical angle recommendations of keeping my propeller shaft lined-up properly between the transfer case, and rear pumpkin. In order to do that, I had to loosen my motor mounts before, and re-tighten them after T-Case drop brace installation. What you have done to set-up your XJ is a superior one compared to my lesser required 'lift-type installation', yet sometimes we overlook small things that 'bind-up' things, lol.

You say that you have replaced various mounts. Well the cause of my shaft moving sideways was due to a failed transmission mount. Nowhere could I find the proper replacement pad for my year set-up. In fact the OEM parts numbers would be on the outside labeling, but the part inside the box would be wrong. They were most likely made in china. The local three parts stores, and various internet stores had the same issue, i.e., different parts, or pictures to the correct numbers given.., and all but one store had to order making the down time really long.., sheesh!!!! In order to bypass the several wrong parts I had to order the complete assembly, (off of the net), which although costly, adding a few more down days.. solved the sideways movement of the shaft. The cost to get just a regular mount was around eighty bucks, and the complete assembly was just over a hundred, and a quarter bucks.., hmmm.

So, after all of the wordiness above the only tip I have is to check/and/or relieve your motor mounts, and see if you can get a better vector. or alignment. On the other hand I have read that some must change the welded mounts of the rear axle to solve your issue; in order to obtain your ride height, to get a proper shaft alignment, and to not eat up 'U'-Joints. But then.., lol, I am just lurking in this side of the forum as I find what you all do to the XJ just amazes me, and the motor mount adjustment tip I have offered may not fix your problem.., but it IS something I ran into when I wrenched-up for a minor lift.

Happy Trails...

I think I've got the mount on the right way. I've also got a 3 peice cross member on there. It's not the factory one anymore.

those darker lines on the right are where the bolts are. Photo was taken from the side with the tcase so the rear.

The whole assembly is more towards the drivers side. I put the mount on the same way the old one was on so maybe that one was on wrong to begin with. The mount that was on before was from the PO.

The more I think about it it might be on there backwards. I'll try flipping it around when I get home tomorrow and see if that fixes it.

The mount was on backwards. Thanks for the help GoSlowGetStuck!

C.Ableman said:

The mount was on backwards. Thanks for the help GoSlowGetStuck!

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No problem, glad you got it figured out!

An FYI, the 2000-2001 transmission mounts have a different offset and will cause alignment problems if accidentally installed in an older model.

Should not matter because misalignment in something spinning is unaffected by the direction in which it is misaligned. Many differentials are offset side to side and jeeps lifted without issue. There is something else wrong if you do indeed have the correct mount installed properly