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Thump from rear end when cold


TJ Addict
Nov 6, 2019
Best way I can describe it is when a car is parked on pavement for a long time the tires can get a flat spot. Then if you try to drive it you can feel a little thump each time it hits.

Same thing, 99% sure it's from the rear. And it goes away after driving and warming up. Only really noticeable at very low speed, and the frequency is what you'd expect from *something* happening at the same spot every tire revolution. No, it's not a rock in the treads, and again, goes away when cold. I feel it in the morning rolling up to the stop sign down from my house, and leaving work in the parking lot. But arriving at home or work after my commute I can't reproduce it.

Rear suspension is all new. Only stock component still there is the sway bar, everything else replaced in the last few months. 2.5" OME springs, Ranch RS5000X shocks, JKS track bar, MC control arms, JKS end links for sway bar, Moog bushings on sway bar.

This issue predates all of that and seems to have been unaffected by any of it. Noticing it more as weather is getting colder, so seems to be temperature dependant.