Death Wobble after lift

Rereading, when you have someone steer while you observe, is that person turning lock to lock or bouncing the wheel back and forth? I find things most obvious with the latter, and the engine off. I also had an assistant back up in reverse while I observed the front axle, as it was shifting when the brake was released. It makes any slack in the control arm bushings pretty obvious.

My pitman shaft was pretty obvious, but it was also leaking.

Those new rear leaves come with a main leaf and bushings?

I've had several of these with the non disconnect axle and prefer it over the alternative. Get shafts for an ABS model, note the extra material. Never had an issue related, it's not the axle. You might check the play in the compensating joint in the front shaft and pinion, but I feel that's unrelated and produces its own symptoms.

I've lifted a couple now to four and a half, both times with the original track bar and pitman arm. Actually, one has a ZJ pitman, but no drop bracket or adjustable track bar. Other than pulling the axle over just noticeably, they drive fine. It should be noted that at four and a half inches, the joint on the factory track bar doesn't hold up to off road use for long, and I wouldn't endorse it as a long term setup.

Perhaps you should check that stabilizer now that it's become more intermittent. It should be positive at any point in it's range of motion. If it pulls light for a quarter inch or so, it's done. There's a chance you resolved the majority of the cause, but driving it in the meantime may have killed the stabilizer. I've had those which drove fine without it, but might be set off by a certain series of bumps in the road. Might not have a problem for weeks, such that I'd forget I needed a stabilizer.

burntkat said:

Pretty sure I said the wheels and tires are new.
That said, I'm going to swap over the wife's ZJ wheels and tires. I had a similar problem with it last year that was solved by replacing everything.

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Figured it was a reach. I also have the attention span of a gnat.

Bent said:

Figured it was a reach. I also have the attention span of a gnat.

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Hey, absolutely no problem. I appreciate the input. I can totally relate about attention span....

Bought the KOR death wobble pdf hoping to gain some extra knowledge on the issue. Glad I didn't pay full price. While I did learn something new, it would have been money better spent elsewhere. Oh well.

Will have my son shift into 4lo and torque the drivetrain as I observe, tomorrow. Maybe that will show me something.

I'm considering putting a KOR HD bushing in the IRO trackbar, but I really don't think I buy the marketing BS that it would be a solution, anymore than I believe that rubber bushings are so superior to poly.

For what it's worth, I had mine in full time when I observed my bushing slack, but part time should be just the same. I have a good bit of slack in my 300k mile original bushings and it drives pretty well without a stabilizer.

Pay close attention to the bolt heads and nuts during your observation, body side and frame.

Had the boy shift into 4Lo and load up the suspension. No movement observed in the bushings or control arms. Even though I have a bushing kit, I'm going to leave that for last.

I did see about 1/4" of movement in the steering dampener. Removed it(8 month old Rough Country part) and inspected. No dead spots, but the bushing in the axle end appeared to be for a 1/2" bolt, leaving slack as it's 12MM or so. Replaced the hardware with GR8 1/2-13X2.5" hardware, and went ahead and put a new Moog dampener on as well. Granted, it's the cheapest dampewner Moog makes for this application.

I am considering biting the bullet and getting the OME $90 unit. Yes it is by some considerations "not a fix"- but if it makes the DW go away, then it's a fix...

I'm going to go ahead and buy new Moog balljoints as they are one of two things I've yet to address- balljoints and control arm bushings. Once those are done, EVERYTHING up front that rotates/slides/rolls will be new, from the steering box to the shat ujoints.

Still haven't done the driver side shaft joint (everyone in town that stocks a "Greasable" ujoint for the application, presently is only able to supply nongreasable- ie, their joints are defective- supposd to be greasable and aren't. I won't run a non-greasable joint), but it is nice and tight and honestly perfect.

I did feel a tad of slop in the brand new TREs. I am running the same joints on the wife's ZJ and they are fine, however. I won't replace them yet as they can't be the problem- I can feel but not measure/see any movement. Going forward, however, I will use Moog TREs only. I just won't buy them at the LAPS, no sense paying 4X the price.

I also saw a tiny bit of movement at the brand new IRO track bar system's frame bracket joint. IE: the bushing there moves just a tiny bit. I feel it shouldn't move at all, especially for the price. It's a good kit, but it escapes me why they kept the 7/16" bolt at the bracket end. I will be removing their bushing and going with a poly bush that will allow a 9/16" bolt, and will drill out their frame bracket to suit. Basically the same thing I did at the axle end of the trackbar, in order to run the Clayton HD Bolt and bushing kit. Then I'll put some real torque on it and nail that sucker in place. Oh, I'm also upgrading the joint at the bar from the bushing to a Currie Johnny Joint.

burntkat said:

Also, I balanced the wheels on all my vehicles myself. I know the balance is dno.

Also, running Centramatic balancers, so they are actively balanced during use. Balance is absolutely not the issue

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If you have balanced the wheels with mounted tires then it should be OK to eliminate the Centramatic balancers from the fault finding process by not fitting them to the Jeep. Put them back on when you have found the root cause of the problem.

My wife's Wrangler had a tire carrier oscillation that I refused to believe was caused by an out of balance tire. After months of her complaining I finally considered that perhaps airing up at a gas station that had oily compressed air may have caused the balancing beads inside the tire to clump. I had all five tires demounted and the balancing beads had stuck hard in fixed spots inside the tire. I vacuumed out the tires and balanced them with conventional rim weights and the problem was resolved.

MJR might remember the same thing happening on his Jeep before we set off for the Rubicon many years ago. It's easy to believe something is working as expected, much better to prove it is by elimination.

Long since done. They work perfectly on the ZJ, they aren't the issue. I took them off and can hear the shot moving inside.

burntkat said:

I also saw a tiny bit of movement at the brand new IRO track bar system's frame bracket joint. IE: the bushing there moves just a tiny bit. I feel it shouldn't move at all.

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It came from the factory with a bushing which deflected a little, I don't think that's it. I also don't think an expensive stabilizer is any better than a cheap one in terms of initial performance. Have you tried driving without it? See if it gets exponentially worse or stays about the same.

I just crammed pipe spacers in mine and some cheap bump stops from amazon for a four inch lift. Bolted the same shocks back in, and it drives fine on the street. This should not be an expensive adventure.

I did much the same with the initial lift on my 90. I agree

I pulled the IRO bar out and installed an old RE bar I upgraded with a Johnny joint. This is not to speak ill of IRO, I just happen to have the spare bar laying about, and a JJ that fit it. Installed and all the motion in that system is gone.

But now it is apparent that every one of the parts house brand, brand new tie rod ends has a little bit of play. I'm ripping them out and returning them, will install Moog brand parts as well as the V8 ZJ driver side tie rod setup.
I still have Moog ball joints to install, just haven't gotten to it yet. It's freaking cold here (30 degrees) which some of you play in, but I'm a southerner and not wired for this crap!

Will check ride with the new track bar setup tomorrow, and report findings.

Check ride went very well. The majority of the DW seems to be gone. There is still some, and I know that will soon be too much if I let it go, so the hunt continues.

Toward that end, I'm replacing all the parts house brand (Master pro) tie rod ends with Moog parts. Also doing the V8ZJ tie rod upgrade while I'm at it. I got all the parts off of Amazon for $220. Considering that one of the same parts alone (long side tie rod end) is $120 alone locally, that's a significant savings.

Parts are expected by the 18th (Thursday). Weather looks to be good this weekend, and the JJ for the IRO trackbar should arrive tomorrow. I already have the V8ZJ tie rod upgrade for the wife's 94 ZJ in hand, so anticipate a lot of front end work on both trucks this weekend. Ironically, her ZJ has *massive *play in the tie rod ends and yet is silky smooth up past 80mph, with a 3 inch lift and factory trackbar. I just replaced the TREs on her ZJ last year with parts house bits, too. They have gone to shit in a year, and the ones I just put on the 97 XJ already have noticeable play. Lifetime warranty will be claimed - and cash refund only, please and thank you. I'm only going to use Moog front end parts from here on. Lesson learned.

Just an update: Dodged rain and cold a few weeks ago and replaced all the MAsterpro TREs with Moog, as well as the V8 ZJ tie rod upgrade. Did a very cursory alignment.

The truck tracks true now with only a rare instance of light DW. I haven't been able to nail the alignment due to weather and my son's work schedule. Hope to be able to this weekend , and put in the front receiver hitch. Hopefully, the DW issues are completely resolved thereafter.