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Death wobble help


Tjbythebay

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Apr 18, 2020
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Seattle Washington
Almost every time I hit 40 mph the car shakes very violently and I have to slow down to 30 mph to stop the wobble. I checked the suspension and everything looks snugged up and looks okay. What should I look for to get this figured out?
 

Lou

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Jun 16, 2016
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Long Beach
Wheels and tires would be #1 culprit. How old are they? Are they worn? Last time they were balanced?

for suspension components you need to perform a “dry steering test” and pay close attention to the trackbar bushings.
 

Chris

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Have the wheels and tires balanced and then check the torque specs of the track bar bolts as well.

Perform a dry steering test as well, as this will be telling.
 

JEEPCJTJ

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I might be wrong but I don't think real DW starts at any certain speed and will stop by going 10 MPH slower.

I do think your problem is tire/wheel related. Six months after fixing my DW with OEM wheels and new tires I ended up with some serious vibration that was so bad that I thought my DW was back until it stopped at about 10 MPH slower. After that happened a couple times I decided to speed up when it started and it disappeared about 10 MPH faster.

It turns out at least one, if not all, of my wheels were "rebalanced" by an unbelievable amount of mud packed into the back side of the spokes. An hour or so with the pressure washer and all was well.
 

Sancho

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1. Check your tire pressure.
2. Then rebalance if needed.
3. Also recheck trackbar bolt and steering linkages... do a dry steering test and also get jeep lifted on the frame to check track bar bolt.
 

John LaFramboise

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Jun 26, 2020
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Burlington, KY
I'm a firm believer in dynamic balancing. With static balancing your tires get out of balance if your tire spins just a little on the rim. Every time you pick up a little mud or rock, your wheels and tires become unbalanced. With dynamic balancing, the balance media constantly moves to where it is needed. There are two basic types of dynamic balancing, balance beads (several brand names) or a mechanical device that works on the same principle. Balance beads are much cheaper and it doesn't take very much. For example, my 33x12.50R15s need only 8 oz. per tire. Most brands come with a little bottle and tube you use to insert the beads through the valve stem with the tire deflated. I use a brand that sells a bag within a bag so you can just throw the bag into the tire if you have the bead broken down or are mounting a new tire. It costs about $12 per tire. Since off roading seems to change the balance of a tire quite often from chunking, knocking off weights or picking up mud, dynamic balancing is very popular with off road enthusiasts.
 
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Tjbythebay

Tjbythebay

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Apr 18, 2020
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Seattle Washington
What
Wheels and tires would be #1 culprit. How old are they? Are they worn? Last time they were balanced?

for suspension components you need to perform a “dry steering test” and pay close attention to the trackbar bushings.
what is a dry steering test?
 

Jerry Bransford

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what is a dry steering test?
With the tires on the ground and a helper doing quick repeated 10-2 steering wheel turns, you watch the steering system and look for unwanted slop/looseness where things are bolted together. Especially with the track bar.

The usual trigger for Death Wobble or shimmies that are not as violent is an imperfectly balanced front tire. Something being loose like the track bar can easily turn a mild shimmy into violent Death Wobble.
 

AndyG

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Death wobble at a certain speed - on a TJ , is almost always going to be a tire or tire/wheel issue.

Death Wobble caused by a bump, which is what we call PMD (passive death wobble) at TJ Academy, means something that is involved in the steering when you hit a bump is at play... That is often the track bar, as it centers the axle as it travels up and down.

An exception is where I've seen it on an F-250 at 80 mph, and it was a bad track bar bushing allowing it, and it took that speed to get the harmonic going.

Another weird exception I know of is an improperly balanced brake rotor was installed on a Jk

Non of the above are all fast and hard rules ... because most Vehicles this age just aren't in perfect shape... Except for mine & Jerry's...😆 ... You can have any combination of tire imbalance and worn components working in conjunction.
 
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AndyG

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if you will go to the homepage and go to the benefit section you will see where you can apply for death wobble insurance.,. The way it works is we get a bunch of people to send me $20 a month....and I purchase a bunch of upgraded steering components and put them on my Rubicon. Then I'm guaranteed never to have death wobble.

You can get a bump steer rider for $5 extra.
 
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Tjbythebay

Tjbythebay

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Joined
Apr 18, 2020
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9
Location
Seattle Washington
With the tires on the ground and a helper doing quick repeated 10-2 steering wheel turns, you watch the steering system and look for unwanted slop/looseness where things are bolted together. Especially with the track bar.

The usual trigger for Death Wobble or shimmies that are not as violent is an imperfectly balanced front tire. Something being loose like the track bar can easily turn a mild shimmy into violent Death Wobble.
I took my Jeep to get my tires balanced and they said they could not do it because I run spacers on my Jeep?! They also said I am getting this wobble because my bushings in my control arms are shot. Would my control arms cause this wobble?

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JEEPCJTJ

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I took my Jeep to get my tires balanced and they said they could not do it because I run spacers on my Jeep?! They also said I am getting this wobble because my bushings in my control arms are shot. Would my control arms cause this wobble?
The balance issue is because you need a better place to get your Jeep work done. I'd guess that the same thing applies to the control arm bushings. Someone will correct me if I'm wrong on that.

Answering a couple questions may help us help you.

How long have you had this TJ?
How long have you had the wheels and spacers and what size are both of them?
How long have you had this death wobble?
 
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Tjbythebay

Tjbythebay

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Joined
Apr 18, 2020
Messages
9
Location
Seattle Washington
The balance issue is because you need a better place to get your Jeep work done. I'd guess that the same thing applies to the control arm bushings. Someone will correct me if I'm wrong on that.

Answering a couple questions may help us help you.

How long have you had this TJ?
How long have you had the wheels and spacers and what size are both of them?
How long have you had this death wobble?
I bought the Jeep 3 months ago and it already had the wheel and tire setup on. Not sure how thick the spacers are but tires are 33 in.
 

Sxklaw

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Feb 16, 2019
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Nj
I had the same issue when I bought my 04. I got a lot of different answers from different tire places. I wanted to get new tires, springs, shocks and a 2.5“ lift as my first upgrade anyway. All I can say it doing that fixed the wobble for good, plus improved the ride overall like you would not believe.
 

Goatman

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Apr 23, 2019
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Upstate NY
First off I would make sure you have a stock steering setup. Stock pitman. Steering joints all tight. Trackbar bushings good. Try rotating the tires front to back. If it is a tire problem that should help. If it's still the same then it's more than just tires.
If you can post some pics of the front steering you have there are guys here with eagle vision that can notice the smallest problem.
 

Jerry Bransford

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I took my Jeep to get my tires balanced and they said they could not do it because I run spacers on my Jeep?! They also said I am getting this wobble because my bushings in my control arms are shot. Would my control arms cause this wobble?
It's possible bad bushings could make it easier for DW to develop. But bad bushings never actually cause DW, they just let it develop more easily when it is triggered by something else... like imperfectly balanced tires.

The spacer thing is when, to use a famous Blaine term, the shop's lawyer fucktards are too liability conscious to allow them to touch spacers. Find a shop that doesn't care or get rid of the wheels that cause you to need spacers. I had a local Discount Tire store refuse to work on my tires because I had a 1/8" wheel spacer up front, it wasn't even one of those big huge 1" spacers some like to install. Then they got a new manager and he had no problem with that my 1/8" spacer. Fortunately I was able to stop using that spacer.

I'd sure focus on tire balance. Every single time my TJ developed DW over the past 24 years it was from a bad tire balance.
 
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Goatman

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I agree with the balance issue as the root cause. But normally by the time the DW sets in there are some additional parts needing replacement too. Even just old rubber can cause a once balanced tire to become out of balance. Also being parked for a long while, although less common now than with bias ply tires, can cause a flat or hard spot that can cause problems too. I try to put new tires on every road vehicle I purchase. It's part of my initial complete fluid change and complete check over of the vehicle.