I have a clunk in my rear suspension when hitting bumps. It seems to be not as loud or happen as much when the car is fully loaded. I thought it was the rear shocks so I swapped them out this weekend. Four broken off upper mounting bolts and an entire afternoon later its still got the clunking so it wasn't the shocks.

What else could it be? Can the rear sway bar bushings make a noise like this? On my old XJ i had a few years back the rear sway bar went in the garbage pile and I always thought it was a very fair compromise for the bit of a downgrade in handling for the upgrade in articulation so I will probably end up doing the same on this XJ. So if its the sway bar that would be nice but if not what else might it be?

 

your u-bolts for your leaf springs could be loos and when you hit a bump your leaf springs move back and forth, or a rusted down bolt. check both

 

x2 with checking your u bolts...my leafs are shot and are pretty noisey and make for a rough ride over bumps and what not

 

Okay this one may sound a little off-topic but here goes.

I HAD the same problem for almost a year.
After changing shocks 3 different times with different manufacturers and going over the entire rear suspension countless times, I found the culprit.

It wasn't even suspension related.
It was exhaust related.
The upper bend of the tailpipe (that goes over axle) was making contact with the body. My exhaust hanger drooped enough to cause the pipe to get closer to the body than normal, and when hitting a bump the system flexed enough... well you get the picture.

A couple of new hangers and a fresh tailpipe...all is quiet back there.
Thank goodness too, I was starting to lose my hearing from the constant radio volume increase to drown it out.

Check the clearance between your pipe and the body. Use your hands, visually...everything will look fine. Also, check the exhaust clamp on the rearmost hanger...if the tailpipe is a little loose, it can also hit the springs or tank.