Need Advice on Deathwobble

[SuicidalPenguin]

I've heard everysay that the trackbar is usually the leading cause of deathwobble. What makes the trackbar cause it? Is it just loose bolts/bad bushings, or is it the pull on the axle after lifting?

 

I'm asking this because i didn't have deathwobble, but when i put 2" coil spacers in and drove it the day after I had it (yes, i did get it aligned). I've since been under there, and the bushing looks fine, the bolts are nice and tight. I just don't think the trackbar's the culprite. What can change in 2" that can cause it? Is it possible that the driveshafts angle's are too steep causing it to vibrate into a deathwobble?

 

FYI, my shocks and steering stabilizer look pretty beat up.. if that makes a difference.

[CWLONGSHOT]

This is SUCH a beaten topic!!! I mean SO MUCH has been written on the subject one would think everyone knows what it is and how to fix it.

 

It can be MANY things or it could be a number of marginal things. I mean it could be a thoroughly trashed bushing, or a ball joint that only a bit loose combined with TRE's that probably should be replaced soon... Catch my drift?

 

Track bar, out of balance tars, ball joints, CASTER, TOE IN, worn TRE's HUB unit bearings, control arm bushings, steering box...or any combo of those + some more I have missed...Death Wobble is something you will never forget. its REALLY bad shake your teeth from your head so badly you need to sit by the road side for a time before driving again. If it wasn't that bad its just some wobbles and likely just minor worn parts..

 

If all you did was lift 2" and DID have a alignment and toe in was adjusted, I would say the CASTER is your problem. As you lift you loose Caster. IE the front wheels move rearward with in its arch of movement.

 

 

FYI, Usually 2" is not enough to cause this.....Are you SURE that 2" spacers is all you changed?

 

CW

[SuicidalPenguin]

thanks CW. I realized it's a topic that has been beaten to death, although all the writeups or threads i've seen it always emphasizes so much on the trackbar that i don't find alot of it useful.

 

I drove the hour and a half highway trip to my dad's, no problems. Put in the rollcage and stuff then the 2" coils, and on the hour and a half trip home, i almost ended up in the ditch because of the deathwobble.

[Bounty Hunter]

A trackbar isn't the cause, but merely what allows DW to happen once the tires enter a wobble that would otherwise be prevented by good parts.

 

You can't tell anything by looking at the track bar ends. You need to have somebody bounce the steering wheel back and forth off of full lock while you watch both end of the track bar. This generally shows play in the upper TRE end of the trackbar.

 

Otherwise, check for cracked control arm bushings as well.

 

Forget about the driveshafts, any driveline vibe is totally seperate from and can not induce death wobble.

[CWLONGSHOT]

BH is absolutely correct. I like to remove the Track bar for inspection, too many times people have said OH I CHECKED IT, ITS FINE. Only to have me or another mech find the TRE or the bushing is shot.

 

Just last week, my neighbor down the road stopped in front of my house. he said, I always see Jeeps here, do you know anything about what is happening to the front of my truck???? He had just spent about 300 bucks for two new tars, and allighnment and a complete front end inspection. He was told everything is fine.....only problem, he still has DW.

 

I had him come back later that day and we removed the TB to find the axle end bushing was TOAST and the TRE was getting loose. I threw on a spare I had and he went off to the parts store for his own.

 

My BRO-IN-LAW bought a 87 MJ one ton about two months ago. GUESS WHAT...the PO sold it because it was not safe to drive!!! DW to the EXTREAM!!! the steering box was loose and easily tightened up with the adj screw. the TRE on the TD was never tighteded!! Uou could litteraly push the TD up about 1/4". What a BUGGER that was to remove, All it did ws spin!!! Now it drives like new!!! about 60 bucks spent and couple hours time.

 

Because of what you have done. I would look close at the TRE on the frame end of the TD as well as the CASTER, if you do not have an adj LCA's you could add a couple shims to your frame end LCA brackets. It will not take much as 2" is usually not enough to put you over the edge, but who really knows...

 

Good luck,

CW

[Eagle]

I've heard everysay that the trackbar is usually the leading cause of deathwobble. What makes the trackbar cause it? Is it just loose bolts/bad bushings, or is it the pull on the axle after lifting?

You heard wrong.

 

This is proof positive that you can't believe everything you hear (read) on the Internet.

 

Death wobble is a complex phenomenon involving a harmonic imbalance that transfers from one front wheel to the other at a mutually-reinforcing frequency of oscillation. There is no way on God's green earth that a loose or worn track bar can "cause" death wobble. I drove my '88 XJ for probably 10,000 miles with a severely worn track bar and extreme wander in the steering (yeah, I know ... but back then 10,000 miles was only 4 months and life conspired to not allow time to replace it) and never encountered even a hint of death wobble. I just needed to start turning the steering wheel awhile before I got to the curve.

 

Death wobble is "caused" by a number of interrelated factors. In fact (or, more accurately, IMHO), the most prevalent contributing factor is tire balance, not track bar wear. However, worn components such as tie rod ends and ball joints, as well as hub/bearing units, can also play a role. The second most common contributing factor is tossing in a lift that reduces the front end caster angle.

 

The worst instance of death wobble I ever experienced (and the ONLY one, until earlier this year) was in a totally stock, brand new 1999 Grand Cherokee WJ that had never been taken off road or abused. The DW kicked in on a state highway in New Hampshire. There was no warning whatsoever. I was 200 miles into the trip. The vehicle had never exhibited DW before, and it never did it again after.

 

Bottom line: there is no simple cure if you have DW, but I will state with 100% certainty that a track bar cannot "cause" it.

 

I agree with Longshot -- have your caster checked. The 2" lift reduced the caster angle. Those shims in the frame pockets for the LCAs adjust caster. Add enough shims to get the caster back where it was and I think your DW will disappear.

[Stumpy]

i have an odd question about DW. woulda/coulda a broken motor mount cause DW?

[Eagle]

i have an odd question about DW. woulda/coulda a broken motor mount cause DW?

No.