Ari Freeman

I just added adjustable rear control arms to my 2 door jk. It has 3" lift on it.
I'm now hearing a thump noise coming from the passenger rear side. To address the problem, I'm planning on installing the Rock Krawler coil correction wedges.

Has anyone installed them? What's the installation process? Do I need to take off the springs?


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resharp001

Is your rear TB bolt on the frameside hitting the bumpstop perch? If you extended the rea arms to stretch the wheelbase again, this can happen when going over a big bump. When does the thumb occur? Can you replicate it at will? A good way to narrow down rear suspension noises is to get on one side of the jeep, put two hands on it and get it rocking side-to-side really good. That gets the suspension in motion and typically brings out any noises.

Sv_dude

I had issues with my track bar hitting my coil springs. I adjusted my lower control arms a bit to fix it. If your coil springs were bowing like mine then yes, you’ll need corrective action. I’d suggest that instead of the wedges, find a shop to either raise the back end of your current perches or weld in new perched that will give your spring perches the proper angle.

I only adjusted my control arms as a temp measure. Once I weld in new spring perches, I’ll adjust my control arms again so that my diff is pointing up a bit more.

Ari Freeman

After looking at it, I think this is what happening. That bolt and nut are sticking out right above the perch.

Is switch the bolt the opposite way around a method of resolving it?

Thanks

resharp001

Yes, hopefully that gains you the clearance. That is all I had to do years ago that I recall.

The other similar issue I recall is moving the axle back caused the sway bar links to lean forward and they would knock against the upper control arm frame side mounts. That required repositioning the sway bar.

karls10jk

I added a stiffener up top (don't recall why) and the bolt was contacting the rear perch. A little zip with the grinder and it wasn't an issue- I just notched the bumpstop landing pad.

hivoltagedriver

Just another thought. After putting some miles on the new arms, double check that everything is tight. A loose control arm bolt will thump too under braking or acceleration.