Anyone know what can cause a squeaking noise when going over sharp bumps quickly in the rear suspension? Doesnt happen during mild bumps, has to be something sharp that jolts the rear suspension quickly. It squeaks pretty high pitched, not too loud but slightly noticeable. I have tein S techs and progress RSB(yes the sway bar bushings have a lot of lube)

 

I have been having the same problem. I have koni/H&R sports and progress rear bar. I have gone over everything, and bushings are lubed on the swaybar as well. It has to be a pretty quick/sharp bump, and It doesn't do it all the time. I think I have narrowed it down to warmer weather (didn't hear it over the winter months).

Thought maybe it was the Ingalls rear camber bushings at one point, but the Ingalls have been removed.

 

My first guess would be either sway bar links or strut mounts. Usually if it's the strut mounts,the sound will be heard just as clearly inside the cabin as outside.

 

Did you ever figure out what it was? I’m having this problem right now.

 

I had that problem in the front. Turned out to be worn strut mounts. Considering what you have to go through to replace them, you're probably better of replacing the whole shock & spring combo at this age. I did. Be sure to do both sides!
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