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.