Death wobble is the result of slack (wear) in suspension or steering. There is so much nonsense on this topic.
Track bar is usually the first place to start.
Finally control arm bushings.
Sure other things will cause rough ride but it's the worn out parts above that prevent the suspension from responding properly. Bumps in road, out of balance tires, etc trigger the wobble but properly working suspension can dampen the movement.
2000 WJ, 2" Lift w/ 160,000 Purchased w/ 145,000 The WJ needed tires, lifted the jeep and R&R all suspension parts from Iron Rock on the rear because of a metal on metal noise. Alignment everything was good.
Recently I noticed a bushing problem with the original front upper and lower control arms. Replaced the arms with Iron Rock adjustable arms and new adjustable Track Bar. All lengths were set to factory. This was recommendation from Lift kit supplier. Test drive and "Death Wobble". Okay what changed? Because the upper and lower ball joints were never changed might as well change (MOOG Racing Parts). During the tear down found bad rod ends and they only had approximately 7,000 miles. Updated rod ends to Moog Racing Parts.Found steering box tight. Test drive and Death wobble but now it was at a higher speed. Took it in for an alignment and problem solved. I save all of the records of maintenance and when we compared the last alignment to the new alignment the caster came into spec with the cross castor in spec as well. all the testing was done with steering dampener removed because it can mask a problem. The bad bushings and old alignment were offsetting a Caster problem. With the new control arms the axle is now in the correct position. Death Wobble gone and the vehicle drives much better.
If you lift a vehicle the associated Death Wobble parts should be replaced with a god quality replacement parts. If you find everything tight and in good working order get the vehicle aligned by a shop familiar with Jeeps. Hope this helps.
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