I'm running out of components to check here and hopefully one of you guys may have an idea. The problem first started when I installed BC coilovers and hotchkis sways. Tons of squeaking, clunking, and other stuff going on in the rear. They are off and the car is back to 100% stock in the rear. Now its down to a clunk from the driver rear side. The car is a 13' with 29k miles. I've done the following to troubleshoot..

1. Re-install the rear spring to make the both rubber pieces, top hat and lower piece, are installed correctly and are sitting in their place.
2. I've ensured there is pre-load. When you jack the car up and reach into the wheel well, the spring will not move when you try and grab it.
3. Re-installed the rear strut and made sure everything was to torque specs along with that rubber piece at the top of the strut .
4. I checked the end links and they seem be to in good shape. Both nuts on the end link are tight.

5. The rear control arm bushings all look to be in tact, no cracking of any sort or play. I've sat there for about 30 mins looking at every possible bolt/nut in the rear end and ensuring they were tight or to check any bushings that are shot.
6. I emptied the trunk, including the spare to make sure nothing was jiggling or hitting something.
7. I banged the mid-section, and axle-back of my exhaust to make sure it wasn't hitting my bumper. It was, but very slightly. I fixed that issue and the noise is still present.
8. My buddy sat in my trunk while I went out in the parking lot, the noise I would say is more isolated towards the rear spring area. But, we can't say that for sure.

 

You should verify the exhaust clearance, again. Tough one.

 

Sway bar bushings greased?

 

on the agenda for tomorrow.

the hotchkis did, but I threw the OEM swaybar on which do not need grease. Same noise, not the sway. nelledge described the noise more of a rattle than a thunk.

 

Sry, missed the part about the sways being back to stock, thought it was just the BCs removed, G/L.

 

It was a combination of the rear Strut top nut being loose and the gasket missing between the top of the strut and chassis. And my midpipe exhaust hangar was loose. To all out there, if You think you checked something. Check it again. It would have saved me hours and hours of troubleshooting.

 

Glad you're back to a quieter place, there's quite a few places/parts that can cause suspension noise, and like you found out even the exhaust can come into play.
BTW, did you go back to stock because all the noises were driving you nuts or are you going to a new plan back there?

 

The noise was driving me insane and I hated the troubleshooting with the BC's. I did that with my old maxima and BC's and don't want to go down that road again. My new plan is either go with a spring (eibach, H&R, s-tech) that drops my car similar to what my BC's did until I buy better quality coilovers (Stance SS, Tein Street Flex) early next year. Or, stay stock and buy the coilovers sooner.