So when I get one the road with my 1989 4x4 4.0 jeep comanche it drives great. UNTIL I get to about 40 mph then it starts to shake, once it hits 48 MPH it stops shaking. I checked my tires to make sure they where tighten all the way and all. they are nothing is wrong with the studs. I asked my Girlfriend to drive in front of me to see what happen when i start to shake. She said my whole front axle moves back and forth quickly then when i get to 48 it sits still. What are main things i should check for this problem? pictures help alot! thanks! And also this happen after I went mudding I noticed it right after that. Also when i turn every once in a while i hear a clunk type noise in the front like axle area. please help guys! my daily driver! thanks!

 

I'm not sure how you go about checking this out, but that sounds exactly the same as when my buddy had a differential going out ( I remember the symptoms well because I was the unfortunate soul driving it when it finally went!).

 

what is the differential?

 

wait nvm i know what it is. i just opened up the carrier and had to redo the gaskets but the diffrential works fine when in 4x4 so i dont think it is that

 

trackbar. axle side mount check to see if its ovaled out.

 

Yep. Check the track bar and the bracket.

 

thank you for picture and what are the brackets?

 

See the track bar? The bracket is the piece between the track bar and the driver's side frame rail.

 

The dreaded death wobble.

Could be almost anything, but I had three different issues all contributing to my death wobble and it got a little better each time I fixed something.

I didn't get death wobble until i installed the 3" lift (with 3" backspaced rims). Installed an adjustable track bar so i knew that wasn't the problem...

...until i learned that it apparently wasn't tight enough, and one end was popping, so I tightened her down and it helped. But not enough.

So then I eventually noticed my driver's side wheel hub was humming a bit. On the hoist, it felt pretty tight, so I didn't think it was loose... but I replaced it anyway, and the death wobble went away almost completely.

Still shook a bit but never got out of control, but when I got my new tires, it was 100% cured and has not come back since.

My old tires were so unevenly worn (previous owner never rotated them and I was rotating them monthly to try and break them back in) that they would fight for traction and jerk back and forth. No problems anymore!

 

One of the best, if not the best, write-up on death wobble.


　

　

　

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