theangler

Hey everyone,

So lately when I hit bumps (railroad tracks, bridge connectors, etc), I'm getting crazy wobbles in the steering wheel.

I hit a bad one a little bit ago and barely held it in the road. I pulled over, then back and all seemed well (aside from the usual slight wobble). I checked over the front end components, but can't really see anything. I'm getting a chirping going slow around corners. Two of my tires (31" hercules trail diggers) have broken belts (the back ones). Could that cause such a nasty wobble which I can barely hold in the road?

Please help!

RTorrez1

It sounds like the death wobble. If you do a search you will find a few good write up on what to look for.
BTW, If your tires are real bad. Yes, it can cause a DW. But, not from the rear.

cruiser54

Or, I'll provide Mr Walker's excellent write-up:



　
　
　
My understanding of "death wobble" is this. Somewhere in the vehicle, one or more components is worn beyond tolerances, and when oscillation initiates from a suspension "traumatic" event (hitting a bump or a pothole) or also when a vibration reaches a certain point and harmonic at a certain speed, it causes theother components to react. This is called the "multiplier effect", where one component affects one or more other components as the event travels through the front end of the vehicle.

Death wobble is not uncommon with the XJ. It is even more common with a lifted XJ. Finding the worn component or components is not always easy. It can sometimes be downright difficult. Sometimes it’s obvious. other times everything appears to be okay when you perform an inspection on a hoist, but getting the vehicle up in the air and going over everything with a fine tough comb is always a good first step. It is very helpful if you know exactly how to perform a comprehensive inspection of every single front end part, looking for abnormal wear and or play in that hardware. If you do not know how to do this type of inspection, pay an experienced professional to do it. Be sure to ask them if they are familiar with "death wobble", as not all technicians are versed in this…..

Check out the below link if you would like some extensive reading on "death wobble" causes and cures. From my research, Kevin (the author of this tutorial) is possibly the best in the business with tracking down root cause of death wobble. He does offer hardware for sale that can help resolve death wobble, but even if you don’t buy any parts from him, you can still get some excellent ideas on what to look at in resolving your death wobble.

http://www.kevinsoffroad.com/how-to-...-death-wobble/

Possible causes of death wobble are listed below. Isolating death wobble is a process of elimination and the root cause is not always obvious and it can often be caused by a combination of things! From my personal experience, I would first concentrate on the track bar and the control arms and associated bushings.
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-Front tires out of balance (try swapping fronts to rear and see if symptoms change)
-Tire pressure. Don’t laugh. It’s not a root cause but can exaggerate the problem. Experiment with lower tire pressure to see if it helps
-Improper lug nut torque on wheels
-Front alignment out of spec
-Loose track bar
-Worn track bar bushings
-Worn track bar (check for play!!)
-Bad control arms and associated bushings
-Worn/damaged steering stabilizer (not generally a cause in and by itself)
-Worn/damaged shocks
-Worn/damaged tie rod end
-Bad U Joint
-Bad ball joint
-Loose frame mount
-Steering box loose
-Bad front hub assembly
　
　

Tom Walker