Death wobble.

[eaglescout526]

Yes. Let’s beat the subject down some more….but I’m stumped on this one. 
 

Long story short, I had this issue crop up to where the steering wheel would stay clocked the direction I turned. This was with the new reman steering box. I swapped back to my professionally rebuilt steering gear(a seal failed, I replaced it)and it helped a little but oddly the issue remained despite the issue cropping up after the steering gear change. 
I went through and changed everything(even the 2wd beam!) to new minus control arms and bushings. They’re fine. 
I changed my coil springs back to my original light duty springs thinking the standard duty ones were too stiff, honestly probably a mistake im

about to learn from. 
I also had an alignment done, the guys said my tie rods weren’t tight enough. they could be right. I didn’t have a torque ratchet to check. Still haven’t. Need to go get my ratchet. 
 

Im gonna change back to my standard duty springs. 
 

But I’m asking for the think tank of CC to help brain storm why new parts would be giving my DW.  Would too tight of nuts on the tie rods cause this? My light duty springs?(after all, they were on when I didn’t have a front skid and AC parts, probably an additional 70lbs on the front)

For what it’s worth, it seems entirely suspension related. As soon as I go over say a manhole cover or some bump from a bridge, it triggers. And I’m doing 40-50mph and it doesn’t stop until about 20mph. 
 

Thoughts? 

[Pete M]

what were the specs on the alignment? 

[eaglescout526]

2 hours ago, Pete M said:

what were the specs on the alignment? 

That’s the one thing I forgot to ask the shop for. I remembered the next day that I should’ve asked them for the print out. I’d have no problem taking it back to them. 
But she steers pretty straight. But that doesn’t mean much. 

[Pete M]

I had a bit of not-returning-to-center with Breanne's truck and a professional alignment fixed it.  My driveway toe measurements got it close, but not close enough. 

 

have you changed the front tires at all?

 

[eaglescout526]

I’m considering examining the toe while down there. 
 

I did get new tires after the alignment. Can that have any affect? The old tires weren’t wearing unevenly. 

[AZJeff]

21 minutes ago, eaglescout526 said:

I’m considering examining the toe while down there. 
 

I did get new tires after the alignment. Can that have any affect? The old tires weren’t wearing unevenly. 

Tire balance (and tire quality) can have significant impact on DW.   You put on new (different) tires, you say.   What brand/size/type?  New or (slightly) used?

[eaglescout526]

1 hour ago, AZJeff said:

Tire balance (and tire quality) can have significant impact on DW.   You put on new (different) tires, you say.   What brand/size/type?  New or (slightly) used?

New, Corsa, highway terrain plus, 235/75/15. 

[ThatJeepGuy]

Is the track bar mounting hole on your front beam axle still 11mm round? Any slop in this mounting hole can easily go un-noticed and be the cause of your deathwobble. 

 

Is the steering box spacer (factory is aluminum) still intact and the bolts all tight? Broken spacer and/or lose bolts can cause this.

 

Are your track bar mounting bolts tight?

 

Is your unibody or the unibody seams around your steering box/track bar mount cracked or the rosette welds broken free Causing the unibody to flex?

[75sv1]

'I also had an alignment done, the guys said my tie rods weren’t tight enough. they could be right. I didn’t have a torque ratchet to check. Still haven’t. Need to go get my ratchet.'

Are they saying the taper fit is loose? 

That Jeep Guy brings up if the frame is cracked. That happened to me. Mine was the opposite of Pete M's. Mine was fine. I took it in for alignment. Then DW. That was one the one with a cracked frame. I had one with a 'slotted' trackbar bushing. It would change lanes, but no DW. I have driven with no trackbar attached. Yeah real fun. 

  On my '00 XJ, I didn't get one of the ball joints tightened correctly. or the contact with a curb really loosened it up. 

   Also, the sway bar can affect things.  I didn't have the rubber bushing in some ZJ sawybar links. The front end would float and veer right. I changed to stock XJs with ploy bushing. Drove good after that. 

   Also, what lift and are the upper and lower control arm bushings good? 

[A-man930]

In approximate order of likelihood:

1. Tie rod tapers being loose - hopefully they're not damaged now. 

2. Slotted-out track bar mounting

3. Tires. 

 

Remember this reality: the hardest part on a car to diagnose is the NEW one.   

[derf]

I've had death wobble a couple of times.  Every time it's been worn components.

 

First time it was ball joints.

Second time it was control arm bushings 

Third time it was steering linkages (both tie rod and drag link).

 

The track bar bracket hole opening up is also a common culprit.  Even something as simple as loose bolts can contribute.

 

Unit bearings can be a contributor too but that would have other symptoms.

 

Check all wear components (bushings, ball joints, tie rod/drag link ends).  Make sure they're not worn out.  Then check every single bolt.  Get a torque wrench on everything and double check.

[A-man930]

Use more than one method for checking for loose steering components:

- on Jack stands, left and right by hand

- vehicle weight on tires, dry park test. Put your hand on every component.

- check axial play with large channellocks.

 

At the end of the day, none of these checks will fully replicate the forces applied when you hit a bump at speed. Specifically, you need to get a visual on both sides of track bar mounting.

[A-man930]

22 minutes ago, derf said:

I've had death wobble a couple of times.  Every time it's been worn components.

 

 

I used to be in this camp until I finally had one episode that originated from tires. There was no perceivable out of balance condition, but they turned out to be the cause.  

I would hope that a road force balance check would identify this, unfortunately, I was never able to see this confirmed. I just changed the tires out because there was a good sale 

[derf]

11 minutes ago, A-man930 said:

 

I used to be in this camp until I finally had one episode that originated from tires. There was no perceivable out of balance condition, but they turned out to be the cause.  

I would hope that a road force balance check would identify this, unfortunately, I was never able to see this confirmed. I just changed the tires out because there was a good sale 

I've never seen it where tires were the only factor.  They can contribute, but without other parts being worn, you'd just get a shimmy instead of full on death wobble.

[A-man930]

8 minutes ago, derf said:

I've never seen it where tires were the only factor.  They can contribute, but without other parts being worn, you'd just get a shimmy instead of full on death wobble.

 

If the shimmy happens to match the resonant frequency of the front end, it can run away.  

It was a surprise to me too.  100%fixed with only a tire change. 

[eaglescout526]

6 hours ago, ThatJeepGuy said:

Is the track bar mounting hole on your front beam axle still 11mm round? Any slop in this mounting hole can easily go un-noticed and be the cause of your deathwobble. 

This one should still be fine. I’ll check it. 
 

6 hours ago, ThatJeepGuy said:

Is the steering box spacer (factory is aluminum) still intact and the bolts all tight? Broken spacer and/or lose bolts can cause this.

These are fine. Course I suppose now the spacer could be broke. And the frame is in great shape. I frequently inspect that for sanity sake. 
 

5 hours ago, 75sv1 said:

Also, what lift and are the upper and lower control arm bushings good? 

No lift. Stock ride height. Bushings we’re recently inspected and or replaced while chasing my steering wheel issue. 
 

 

Im leaning that I have wayyy to much castor for the light duty springs. I’m swapping my springs as I’ve been less than pleased with my light duty. I only swapped those due to slight stiffness in suspension but that’s a better trade off than the light duty and quick bottoming out. 

[75sv1]

What shocks? 

[derf]

2 hours ago, A-man930 said:

 

If the shimmy happens to match the resonant frequency of the front end, it can run away.  

It was a surprise to me too.  100%fixed with only a tire change. 

It's likely you had worn components that weren't bad enough to induce death wobble on their own.  With fresh bushings and joints, and all torqued to spec, there isn't enough slop in the system to allow the harmonic to run away with just bad tires.

 

Fix just one contributor when you have many and you can see results.  There are many pieces in the system and they all play a part.

 

When I did ball joints, my control arm bushings were wearing out.  But my death wobble stopped.  Until I put another 10,000 miles on the bushings and they got bad enough.  Then it was the tie rod and drag link that were next not terribly long after.

 

There isn't one magic bullet.  You have to shotgun the front end to really solve it permanently.

[derf]

I'll expand my list of everything that contributes to death wobble

 

1.  Ball joints

2. Control arm bushings

3. Track bar bushings

4. Track bar bracket

5. Tie rod and drag link joints.

6. Steering box 

7. Steering box spacer/mount

8. Bolts/nuts for everything above

9. Shocks/steering stabilizer (minor)

10. Tires (not without other factors)

11. Unit bearings (will have more symptoms than just death wobble).

 

Individually, each one can be minor and not cause death wobble.  Toss together a few minor things worn too much and you get death wobble.  Fix one and it goes away, until the others get worse.

 

It's a problem with a lot of causes that all work together in a gray area.

[eaglescout526]

31 minutes ago, 75sv1 said:

What shocks? 

Mopar JK rubicon shocks. They have been on for a while now.

[A-man930]

1 hour ago, derf said:

It's likely you had worn components that weren't bad enough to induce death wobble on their own.  With fresh bushings and joints, and all torqued to spec, there isn't enough slop in the system to allow the harmonic to run away with just bad tires.

 

Fix just one contributor when you have many and you can see results.  There are many pieces in the system and they all play a part.

 

When I did ball joints, my control arm bushings were wearing out.  But my death wobble stopped.  Until I put another 10,000 miles on the bushings and they got bad enough.  Then it was the tie rod and drag link that were next not terribly long after.

 

There isn't one magic bullet.  You have to shotgun the front end to really solve it permanently.

 

I've been down the path you're describing. Add in the reality that every death wobble "event" is extremely stressful on the entirety of the steering and front suspension system and it becomes an expensive chicken and egg situation.  

I want to agree with you on the tires, but my experience (on my wife's JKU) began with all steering TREs and went on to include overkill measures like a track bar relocation bracket, adjustable upper control arms and a drag link flip. Every other one of your listed components checked good multiple times. 

New tires fixed it. 

I'd wager that, in practice, there is enough slop in the design for tires alone to induce the phenomenon. 

 

/hijack

 

If I'm understanding the OP's current state correctly, he's chasing the wrong rabbit changing springs and caster angle when he really needs to first get a thorough shakedown and properly tighten the front end. 

[derf]

5 minutes ago, A-man930 said:

 

I've been down the path you're describing. Add in the reality that every death wobble "event" is extremely stressful on the entirety of the steering and front suspension system and it becomes an expensive chicken and egg situation.  

I want to agree with you on the tires, but my experience (on my wife's JKU) began with all steering TREs and went on to include overkill measures like a track bar relocation bracket, adjustable upper control arms and a drag link flip. Every other one of your listed components checked good multiple times. 

New tires fixed it. 

I'd wager that, in practice, there is enough slop in the design for tires alone to induce the phenomenon. 

 

/hijack

 

If I'm understanding the OP's current state correctly, he's chasing the wrong rabbit changing springs and caster angle when he really needs to first get a thorough shakedown and properly tighten the front end. 

My DW happened on my JK.  I think, for some reason, the JK suspension design is more susceptible to death wobble as I haven't ever had it in any of the clapped out XJs or MJs I've ever driven.  If anything should have had death wobble, it was those beasts.

[A-man930]

14 minutes ago, derf said:

My DW happened on my JK.  I think, for some reason, the JK suspension design is more susceptible to death wobble as I haven't ever had it in any of the clapped out XJs or MJs I've ever driven.  If anything should have had death wobble, it was those beasts.

 

Same. My MJ back in the day was less than perfect at many stages and it never gave me any trouble. Something about the JK makes it extra sensitive.  However, all of the principles apply. 

[89 MJ]

17 minutes ago, derf said:

My DW happened on my JK.  I think, for some reason, the JK suspension design is more susceptible to death wobble as I haven't ever had it in any of the clapped out XJs or MJs I've ever driven.  If anything should have had death wobble, it was those beasts.

 

3 minutes ago, A-man930 said:

 

Same. My MJ back in the day was less than perfect at many stages and it never gave me any trouble. Something about the JK makes it extra sensitive.  However, all of the principles apply. 

Agreed! My mother's JK had death wobble really bad for a little while, even though it was professionally aligned. My MJ with a tape measure alignment in the driveway has never had an issue.

 

The problem with the JK was caster. And being that everything is new in this MJ, I think I'd start my looking at what the caster is and what could've changed it, like the springs.

[A-man930]

2 minutes ago, 89 MJ said:

The problem with the JK was caster. And being that everything is new in this MJ, I think I'd start my looking at what the caster is and what could've changed it, like the springs.

 

What data do you have to support this claim? 

 

(Not trying to be snarky)