When every thing is working well, this type of steering and suspension works very well. However, when things go wrong, the shake can be very scary and can potentially damaging.
The axle is located side to side by the track bar. The joint on the frame end is made like a tie rod and is susceptible to damage due to corrosion and over extension. Just a very sight amount of wear in this joint can allow the axle to move side to side and can lead to the death wobble shake.
Another base cause of death wobble is the caster angle. The caster angle changes slightly when the XJ Cherokee is lifted due to the unequal length control arms. This angle can be corrected with shims. Very often death wobble can be eliminated by altering the caster angle. More or less caster than the factory recommended settings may be required for your suspension so you may have to experiment.
Worn or soft control arm bushings can lead to caster angle changes and therefore lead to death wobble. Replacing worn bushings are retrofitting polyurethane bushings can correct your steering angles and sometimes eliminate the death wobble.
Another possible source of difficulty are the steering box bolts. The bolts that pass through the steering box and secure it to the frame also pass through an aluminum spacer. Often this spacer corrodes and keeps the bolts form turning. Even if they feel tight with a wrench, they may not be holding the box tight to the frame. Also, this area of the frame is highly stressed by off road driving and larger tires and can break. Any looseness in the steering box mounts can contribute to death wobble.
