93 ZJ has the death wobble...

berg

Member
I am mostly a cruiser guy but my 80 year old dad has a 93 ZJ grand Cherokee V8 that gets the death wobble when it hits any pavement change . You have to be going over 60 to get it...... thought I'd ask here.

I put it on a 2 post auto lift and found no ball joint problems and the steering tre's look good.
I need a source to order sway bar rubber parts and a new steering stabilizer.
( who would you suggest in Utah or SLC county.. ( he lives in provo)
I don't want to buy from brent brown Jeep dealer... $$$
any suggestions on how to check the control arm bushings.. they look ok and I gave them a little pry bar action but found nothing obvious.
Tires are new and matching and balanced...

any opinions appreciated..

Berg
 
Last edited:

gijohn40

too poor to wheel... :(
Location
Layton, Utah
Teraflex is the place to get parts... and if you can look at the trac bar maybe the bolts are loose or the bushings are almost gone... that is what my zj had problems with... next thing would be get a good aliment and make sure the caster is correct...

For more on this do a search cause this kind of post comes up about once a month...
 

phatfoto

Giver of bad advice
Location
Tooele
Even though you should search, I pulled this info off the CherokeeForum.com, ORIGINALLY posted by FrankZ of that forum. Seems it would apply to XJ/ZJ/TJ/WJ Enjoy...

Seems every time someone has a case of death wobble they instinctively feel the need to throw bucks of money at their rig. While a non-issue for some, many folks simply don't have the means to do that.

What's the right direction? Find the root cause of the problem.

New tires? No, not until the problem is resolved. I would move the good tires to the front while troubleshooting.

Start with the basics. With the engine off, have some one move the steering wheel back and forth quickly while you look at, listen to, and feel every moving part of the steering system. Here's a checklist for ya:
Track Bar (TB)
TB frame side bracket and mounting hardware
TB frame side TRE
TB side axle bushing and bolt.
TB axle side bolt hole (wallowed out?)
TB adjusting collar

Drag link (DL)
Dl TRE and castle nut at pitman arm
Tapered hole in pitman arm wallowed out from loose DL TRE?
DL TRE at steering knuckle

Tie Rod (TR) bent
TR TRE's at the DL and at the steering knuckle
TR adjusting collar

Ball Joints (BJ) & Unit Bearing Hub (UBH)
Jack up one tire just high enough to get a long pry bar/cheater bar under it.
While jacking the the heel up watch for obvious and gross changes in the camber of the wheel/tire. This will indicate a bad BJ or UBH.
Have your assistant move the pry bar up and own quickly while you place your fingers on the BJ boots. Watch and feel for any pop or clicking noise.
Grab the tire at 3 and 9 o'clock and try to lift it straight up. movement indicates a bad BJ.
try lifting the tire from the bottom. Movement indicates a bad BJ or UBH.

Toe-in/out
Using a tape measure, check the toe. The easiest way to do this is by measuring the distance between the inner sidewalls at 3 and 9 o'clock. make sure to measure at the same points on the rear side as you do on the front side. Toe-in should be 1/8 to 1/16".

Caster can be measured with a cheap angle finder from lowes, Home Depot, etc. The factory spec is as follows:
CASTER
Preferred + 7.0°
Range + 5.25° to + 8.5°
MAX RT/LT DIFFERENCE 1.25°


Wheels and tires
Check for bent rims
Missing weights
Debris between tire and rim (sicks, splinters, etc)
Unusual bulges on the inner/outer sidewalls.
Properly balanced

Steering Stabilizer...take it off, at least until you've fixed the problem. Steering stabilizers are a band-aid that mask other issues. It does nothing more than give drivers a false road feel.

U-Joints and CV's
Bad U-joints do not cause death wobble, PERIOD.
There are no CV joints on a XJ.
 

jackjoh

Jack - KC6NAR
Supporting Member
Location
Riverton, UT
The phatfoto post should be kept on file so it can be posted each time the deathwobble question is asked.
I went to Teraflex and Dennis did most of these things on my 95 ZJ and it boiled down to doing a static balance on the tires. So far, so good.
 

berg

Member
Thanks for the info..

More on rig:
no lift
stock rig...stock new tires
128k miles
new shocks
I put a prybar on everything under there... I'lll start with the sway bar I guess
and go from there.
 

OrvisKrawler

Captain Obvious
Location
Eden UT
how long has it done it, did it start after you got the tires? i would take it back in and have them rebalanced first, and make sure they put the ones with the most weight on the rear, or better yet if you know anyone that has another set of rims and tires throw those on and see if it still does it, if your in the ogden area I have a set of stock rims and tires for my 95 zj that I know are ballanced good if you wanna swap and see what happens
 
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