Death wobble (don’t see anything loose)

[P_D]

I’m trying to diagnose my death wobble. It’s not a shimmy, it’s a no-kidding, tires chirping, rattle-the-fillings-out-of-your-teeth, violent shake that doesn’t settle until I come to a complete stop.

i have a 3" lift (springs, adjustable trackbar, t-case drop) and 33s. The wobble always seems to happen at 43-48mph in a easy curve to the left. No wobble when curving right.

I have read through pages and pages of death wobble threads on this forum and others and watched lots of YouTube videos and the consensus seems to be that if a Jeep has DW, something somewhere is loose or worn out. I have posted a video to YouTube of me doing the test I have seen several people do:

• I disconnected the steering stabilizer and had my son start the Jeep and move the steering wheel side to side. I looked, listened and felt all the connections in the steering system, and I’m not seeing anything obvious.
• I jacked up the axle and put jack stands under it, lifting the tires off the ground by a couple inches. I put a long pry bar under each tire and lifted and dropped to check for movement in the ball joints.
• I used a large screw driver to pry on the bushings of the control arms.

Can someone with some experience take a look at this video and see if I’m missing something? Is the movement in the control arms too much? Would that cause death wobble?

 

[Jerry Bransford]

The most common root cause of Death Wobble is an imperfectly balanced tire. It's what provides the power to produce that hellish wobble. Something not tight enough, like a track bar not mounted tightly enough, makes it easier to develop. I've had around three fully developed OMG DW over past 25 years of TJ ownership and every one of them had a bad or imperfectly balanced tire involved. 2 of the three also had a track bar that was tight but not tight enough, the 3rd was caused solely by a front tire that had lost its main balancing weight. That 3rd one was my first DW (and worst of all) on my then still nearly new 97 TJ. Still new enough nothing was worn out or loose. Just a bad tire balance.

And it doesn't matter if your tires were recently balanced. Few tire shops give their techs the time to do better than a "good enough" which never good enough for the type of front end the TJ has. Especially with bigger tires which are harder balance well. My local Discount Tire store had to balance my tires 3X in one day before they finally spent enough get them good enough.l to satisfy me.

Now I offer the tire tech an extra $20 tip if he gets them balanced perfect the first time. It helps, most recently 2 weeks ago. He nailed it the first time with 3 well used tires and just 1 new one

 

[D M]

Just something worth mentioning: Make sure your track bar is tightened especially at the axle side. Mine was loose and it was giving all sorts of hell. Also are your control arms torqued? Ive been adjusting angles lately and have found that the jeep will strongly misbehave on the street if its not. Now I never had death wobble, but everything loose definitely was causing issues.

Torque specs if you need them

Track bar @ axle: 55 ft/lbs
Front Lower control arm @ axle: 85 ft/lbs
Front upper control arm @ frame&axle : 55 ft/lbs

Front and rear Lower control arms are 130 ft/lbs @Frame and axle(except front axle)

 

[Sancho]

Check your tire pressures, ensuring they are they same.

As stated above... its probably a tire imbalance thing.

 

[CharlesHS]

Since you have provided a detailed video of testing the TREs, have checked the ball joints and control arm bushings indicating they are in good condition; have you checked the condition of the hub bearings ?
Lift the Jeep off the ground and grab the tire at 3 o'clock and 9 o'clock and test for any play; then spin the tire listening for rough sounds.
As JB and others have posted; make sure a reputable shop balances the tires properly....

 

[03coloradowrangler]

food for thought, are the rims hub centric or lug centric when balancing is required?

I had a slight improvement (enough to notice) in the reduction of out of balance shimmy after requesting the tire shop balance my oem rims/tires lug centric with the finger plates on the tire balancer rather than hub centric.

 

[P_D]

Few tire shops give their techs the time to do better than a "good enough" which never good enough for the type of front end the TJ has. Especially with bigger tires which are harder balance well. My local Discount Tire store had to balance my tires 3X in one day before they finally spent enough get them good enough.l to satisfy me.

Now I offer the tire tech an extra $20 tip if he gets them perfect the first time. It has helped, most recently 2 weeks ago. He nailed it the first time with 3 well used tires and 1 new one

Thanks Jerry. Almost everything I have read and watched has pish-poshed the idea that tires might be the culprit. The trackbar seems to be the most often accused suspect.

I have an appointment this week with the Discount Tire where I bought the wheels and tires a few years ago. I booked it during a typically slow time and I plan to explain to the tech that I need the wheels balanced perfectly and ask for clip weights on the outside and the inside.

Quick question. It may be obvious to others, but how will I know if the tires are balanced correctly? If the death wobble ceases, I’m good to go, but if I drive it and I still get the wobble, how do I know if it’s unbalanced wheels or some other component?

 

[FarFire70]

Just something worth mentioning: Make sure your track bar is tightened especially at the axle side. Mine was loose and it was giving all sorts of hell.

This was it for me when I put in my HP30. Hour commute both ways the following Monday had me under the front with the wife turning the wheel when I got home. It was VERY obvious I hadn't torqued the track bar down at the axle. Lots of movement.

 

[P_D]

Take a peek at the video I made. I’m not seeing any movement on either end of the trackbar, the TREs, the drag link or the pitman arm. Also not seeing any up-and-down movement in the ball joints. But I’m not an expert. There is some side to side movement in the bushings of all the control arms, but I don’t know if it’s a normal amount.

 

[Jerry Bransford]

As soon as it's ready to pick up ask the tech how it went and if he noticed any problems like a bad tire.

Assuming he said it went fine immediately take it out onto the highway and see how it does. If you get a speed sensitive vibration or shimmy he didn't nail it. They'll redo it if you tell them to.

 

[pc1p]

I must be lucky or something - In all the instances where I've seen, fixed or helped fix DW, I've never been able to track it down to tires. Hell, having see so many mismatched and unbalanced tires on shitbox XJs that have never had DW, I was shocked to see so many people reference it as being causal. At my best guess, I would have said contributor and possibly an initiator to DW, but never causal...

Take a peek at the video I made. I’m not seeing any movement on either end of the trackbar, the TREs, the drag link or the pitman arm. Also not seeing any up-and-down movement in the ball joints. But I’m not an expert. There is some side to side movement in the bushings of all the control arms, but I don’t know if it’s a normal amount.

Having an issue with DW myself - traced it to what I hope is the UCA bushing in the front axle, passenger-side control arm. Same speed you're having issues with. No vibrations or tire-related problems that I can feel (my dad was a mechanic for 20 years, so I like to think I'm fairly good at diagnosing tire issues from the driver's seat). You can read more about it here: https://wranglertjforum.com/threads/death-wobble-losing-my-mind.53620/page-3

 

[Jablinski]

I have an appointment this week with the Discount Tire where I bought the wheels and tires a few years ago. I booked it during a typically slow time and I plan to explain to the tech that I need the wheels balanced perfectly and ask for clip weights on the outside and the inside.

If you take your rig offroad, you're better off with sticky weights.
The hammer-on clips get ripped off the wheel very easily by rocks.
I clean and degrease the insides of my wheels before heading to the tire shop to ensure that the stick-ons stay stuck on

 

[AndyG]

You typically cant reveal the issue with a prybar- it takes way more force- a dry test is the best method, and the track bar at each end and front upper control arm bushings at the axle are 2 very good places to start-

it is fixable. Be persistent.

 

[AndyG]

I must be lucky or something - In all the instances where I've seen, fixed or helped fix DW, I've never been able to track it down to tires. Hell, having see so many mismatched and unbalanced tires on shitbox XJs that have never had DW, I was shocked to see so many people reference it as being causal. At my best guess, I would have said contributor and possibly an initiator to DW, but never causal...



Having an issue with DW myself - traced it to what I hope is the UCA bushing in the front axle, passenger-side control arm. Same speed you're having issues with. No vibrations or tire-related problems that I can feel (my dad was a mechanic for 20 years, so I like to think I'm fairly good at diagnosing tire issues from the driver's seat). You can read more about it here: https://wranglertjforum.com/threads/death-wobble-losing-my-mind.53620/page-3

I had an elongated right front stock uca bracket that let the bushing move- sure enough - death wobble eventually ensued, on a sweeping left hand turn- new mount, new johnny joint welded in- really made a difference - fixed the issue and drove even better.

 

[pagrey]

Balance starts it and the worn control arms allow it to get out of hand. You can't tell the condition of the factory control arm bushings by prying or looking at them. If they haven't been replaced they are your problem. The balance is the trigger but arms in good condition should be able to manage most of that. You've already examined everything else pretty closely. I'd do the arms next. Unfortunately the axle side uppers in the front are a total pain but what can you do? Balance is very easy to check, just rotate tires front to back. Two tires are almost never out of balance in the exact same way. If it changes the speed the shakes start you found your trigger but even perfectly balanced tires can go into DW over bumps if the arms are worn. Just my two cents, what I'd do on my personal rig and what I have done in the same situation.

 

[AndyG]

but even perfectly balanced tires can go into DW over bumps if the arms are worn

Dead right. Absolutely- you can have the auto oscillation from tires causing it and basically just taking over the steering - it can be worn components allowing it and tires or just a good bump setting it off, and it can be some of both.

a turn may push connections to one extreme and whatever is loose now has the entire amount of slop available to allow the movement- things tend to run at a more neutral point if no force is applied- this is speculation. But a bushing that moves 1/8” each way in a turn may then have 1/4” to travel. At the same time there have been instances where loose components did not exhibit it and tight ones did.

 

[P_D]

Okay lots of great advice. Let me see if I have this straight: My control arms and bushings have never been replaced, and there is no good way to check them reliably, so I almost certainly need to replace them. This is probably a stupid question, but do I replace the whole control arm, or can I get new bushings and press them in?

 

[pagrey]

can I get new bushings and press them in?

You can get new bushings, I've done it, use sockets and a ball joint press to put them in. If you go off road I don't recommend it. The new bushings can tear out. New arms aren't too expensive from places like rockauto.com. Do what the budget allows.

 

[Kid Mechanic]

… but do I replace the whole control arm, or can I get new bushings and press them in?

As stated above, it can be done. I couldn’t get the better grade of Moog in just the bushing. I went with new arms pre-loaded from Detroit Axle. They use the better K series Moog instead of the budget grade. Cost almost twice as much As individual.

 

[AndyG]

You can get new bushings, I've done it, use sockets and a ball joint press to put them in. If you go off road I don't recommend it. The new bushings can tear out. New arms aren't too expensive from places like rockauto.com. Do what the budget allows.

Posting like a boy dog right there.