Death wobble.

[eaglescout526]

7 minutes ago, A-man930 said:

Does the bolt look worn out?

 

No, has some pitting but not worn down or out. Nothing that compromises the strength of the bolt. 

 

I dont know, that joint feels kinda trashed and like it wouldnt help keep its position. I can always make a side by side clip of the two. 

 

Ill go have someone wiggle the wheel.

[eaglescout526]

Nothin with the steering wheel wiggle. The only sound I heard was the steering gear being rocked back and forth. I felt and watched each joint, nothin out of place. Felt the ball joints and observed, nothing. 

[Pete M]

rotate your tires front to back.  do one side, then test, then the other side.  hopefully you don't find 2 bad tires like I did on a friend of mine's car.    thought I had it licked when I found a legit bad tire (popped cord) up front, but the vibration persisted after I rotated it to the back.  turns out she ran up a curb and ruined both on that side.  

 

 

[eaglescout526]

10 minutes ago, Pete M said:

rotate your tires front to back.  do one side, then test, then the other side.  hopefully you don't find 2 bad tires like I did on a friend of mine's car.    thought I had it licked when I found a legit bad tire (popped cord) up front, but the vibration persisted after I rotated it to the back.  turns out she ran up a curb and ruined both on that side.  

 

 

This will be my next step if a better track bar doesn’t fix this. 
 

Also to add, I found my steering gear under torque spec. 

[ghetdjc320]

9 hours ago, eaglescout526 said:

Nothin with the steering wheel wiggle. The only sound I heard was the steering gear being rocked back and forth. I felt and watched each joint, nothin out of place. Felt the ball joints and observed, nothing. 

Do this with the engine running. You need the power steering to be running to get this accurate. And look carefully at the TB frame mount location on the inner frame rail. 

[eaglescout526]

3 hours ago, ghetdjc320 said:

Do this with the engine running. You need the power steering to be running to get this accurate. And look carefully at the TB frame mount location on the inner frame rail. 

While I do not have a manual steering gear, something I thought of when I read this was what if one had a manual gear? Running the engine wouldn’t yield much to them and wouldn’t such result in the same results if I was moving the steering wheel without the engine running with a power steering set up? Im

just not seeing how running the power steering or not running it will net me more accurate results. Plus a running engine won’t allow me to really hear anything like a popping that I could be feeling in the steering column. 
 

What am I looking for at the frame bracket? I’ve made sure the hardware is torqued to spec and looked for the hole to be wallowed out. Frame is in great shape, no cracks or rust of any kind. Jeep wasn’t really beaten on prior to me. 

[Eagle_SX4]

I just read through this whole thread again and I didn't see it mentioned what your death wobble symptoms were. Such as the steering steering wheel shaking back the whole truck shacking or the maybe like the problem I had, the entire bed would shake. What is actually happening when you experience the death wobble.

[eaglescout526]

Steering wheel will shake but I can keep it under control. Front end vibrates/shakes violently. Won’t stop until I come down to 20mph and under. 

[AZJeff]

If the track bar bolt hole on the axle is "slightly" worn out, you can go a SAE (Imperial) threaded bolt to replace the metric factory one.  The SAE type will be slightly larger in diameter and fill up the hole better.

 

If the axle bracket is seriously oversized, welding on thick washers is the way to restore the hole to the proper size.

 

The factory track bar setup at the chassis end is problematic because of the ball stud type of pivot.  I would switch the bracket AND the track bar to a more conventional style with rubber bushings on both ends, and built-in adjustability

 

[derf]

5 hours ago, eaglescout526 said:

While I do not have a manual steering gear, something I thought of when I read this was what if one had a manual gear? Running the engine wouldn’t yield much to them and wouldn’t such result in the same results if I was moving the steering wheel without the engine running with a power steering set up? I'm

just not seeing how running the power steering or not running it will net me more accurate results. Plus a running engine won’t allow me to really hear anything like a popping that I could be feeling in the steering column. 
 

What am I looking for at the frame bracket? I’ve made sure the hardware is torqued to spec and looked for the hole to be wallowed out. Frame is in great shape, no cracks or rust of any kind. Jeep wasn’t really beaten on prior to me. 

With the engine running, there's more pressure when you turn the wheel and you're more likely to see parts moving that shouldn't.

 

Look for steering box movement relative to the frame.  Look for deflection of the steering shaft at the pitman arm.  Look for deflection in the joints at the axle end of the drag link and tie rods.  Look for the track bar to move relative to the axle and frame.  That includes the bolt/tie rod end moving in the bracket.  Look for the track bar brackets themselves (both ends) to shift.  Look for the tires to rock side to side (camber should not change at all).

 

If any of that happens, it contributes to death wobble.  

[Eagle_SX4]

17 minutes ago, derf said:

Look for the tires to rock side to side

I agree with this. Seems like you have checked most if not all of your steering components. Next should be to check the wheels, ball joints and hub bearings. Any of those could easily cause death wobble if the are worn out enough. Even loose lug nuts could cause death wobble.

[ghetdjc320]

6 minutes ago, derf said:

With the engine running, there's more pressure when you turn the wheel and you're more likely to see parts moving that shouldn't.

 

Look for steering box movement relative to the frame.  Look for deflection of the steering shaft at the pitman arm.  Look for deflection in the joints at the axle end of the drag link and tie rods.  Look for the track bar to move relative to the axle and frame.  That includes the bolt/tie rod end moving in the bracket.  Look for the track bar brackets themselves (both ends) to shift.  Look for the tires to rock side to side (camber should not change at all).

 

If any of that happens, it contributes to death wobble.  

 

And as for the whole “what if I had manual steering scenario”, a manual steering box would have a different gear reduction which would provide the same amount of steering force whether the truck is running for not though the helper may need a bit more muscle to yield similar effects when the truck isn’t moving. You’re looking for the slightest play in components. While driving, the forces exerted on the steering and suspension components are much stronger, so you’re trying to emulate that as best you can while parked. With power steering and engine running, rocking the steering wheel back and forth in short order or turning it lock to lock may reveal the issue. 
 

In my scenario, I noticed the frame side track bar bracket moving slightly “independently” of the frame. It wasn’t huge but that’s where the problem was and no amount of torquing bolts would stop it as the bracket itself is what failed as it is multiple sheets of metal folded and spot welded together in typical AMC/Mopar fashion. In my TJR it was a tie rod end, on my TJS it was the axle side track bar hole. It doesn’t take much. 

[eaglescout526]

 

20 minutes ago, derf said:

Look for steering box movement relative to the frame. 

I can definitely rule this out. I had my bolts loose and I mean loose to where the box moved on my XJ and noticed the steering wandering/slightly unresponsive. I should’ve had death wobble several times over in that case given nothing other than control arm bushings had been replaced on it. 
 

4 minutes ago, Eagle_SX4 said:

ball joints

Brand new spicer joints

 

 

I’ll put the mopar bar back in and see what happens. I’ve never seen anything move that shouldn’t be moving and vice versa when I’ve inspected the front end before. I was doing inspections on the front for my clocking issue and even though I found the track bar bracket to have moved, not once with the engine on did I see the bracket move cause only the turning force/momentum would force the track bar bracket to shift. 

[derf]

35 minutes ago, eaglescout526 said:

 

I can definitely rule this out. I had my bolts loose and I mean loose to where the box moved on my XJ and noticed the steering wandering/slightly unresponsive. I should’ve had death wobble several times over in that case given nothing other than control arm bushings had been replaced on it. 
 

Brand new spicer joints

 

 

I’ll put the mopar bar back in and see what happens. I’ve never seen anything move that shouldn’t be moving and vice versa when I’ve inspected the front end before. I was doing inspections on the front for my clocking issue and even though I found the track bar bracket to have moved, not once with the engine on did I see the bracket move cause only the turning force/momentum would force the track bar bracket to shift. 

Double check that the body of the ball joint isn't loose.  Change them out often enough and the hole gets enlarged.  That can cause issues.

[ghetdjc320]

6 hours ago, eaglescout526 said:

I’ll put the mopar bar back in and see what happens. I’ve never seen anything move that shouldn’t be moving and vice versa when I’ve inspected the front end before. I was doing inspections on the front for my clocking issue and even though I found the track bar bracket to have moved, not once with the engine on did I see the bracket move cause only the turning force/momentum would force the track bar bracket to shift. 

The track bar bracket shouldn’t shift. Try to rock the steering back and forth with power steering on concrete. It also helps to place fingers across both the fixed and possible mobile joints. For instance, for tie rod ends, fingers across the body and joint while using the method above may reveal some movement that is not always obvious to the eyes. 

[watchamakalit]

5 hours ago, ghetdjc320 said:

The track bar bracket shouldn’t shift. Try to rock the steering back and forth with power steering on concrete. It also helps to place fingers across both the fixed and possible mobile joints. For instance, for tie rod ends, fingers across the body and joint while using the method above may reveal some movement that is not always obvious to the eyes. 

Good point on that. Your sense of feel will find it faster than eyes and ears alone many times. 

[Pete M]

gotta use all the senses.   except maybe taste.  probably best to skip that one.

[eaglescout526]

Ok so track bar was swapped, steering was inspected and there was no change. 
 

How ever….

 

What are the chances of the toe in and toe out being too much and causing such? (Guess what I should say here is that the front tire alignment was about 53” and the rear of the tires was about 54 1/2” out)Cause I found them out of whack and dialed them in. So far trying to trigger it hasn’t happened at either 40 or 45. Nor 50 on a clean road.
 

I’m still skeptical of the tire balance like you said Pete. 

[Pete M]

I've had bad toe and bad tires cause it.  or more accurately, correcting one of those things made it go away. 

 

it can be an incredibly frustrating thing to fix because it's likely never a single thing causing it, but at the end of the day, one of the things you address will bring it back under the threshold and go away. 

[eaglescout526]

Yeahhhh this has been a frustrating journey. Most of which I could’ve had corrected in the very beginning when I did the beam swap. But I’ve learned a lot. Also learned impact isn’t good enough for ball joints…anywho! I’m not confident in the new track bar and my clocking issue returned with the mopar bar. So I’ll probably get a new one at some point. 
 

Probably will get the tires looked at too. Just as a precaution. 
 

But I went a didn’t a sanity check drive. 45MPH on the rough road where it would trigger. Nothing. 
60MPH on a road with sewer covers, nothing. I think it’s fixed. Alignment was an issue and didn’t pop up until the previous rookie mistakes were corrected.