Did some searching around, looked through the FSM to see if I could locate something out of place, but I'm not having any luck, hopefully I can get some opinions...

I've got an 87 NA RX7, has silver KYB-IIs on all four corners, looks like the rest of it is stock. My passenger rear is making an awful "clunk" sound whenever I get any quick suspension travel, any sort of bump and I get the sound. If I had to describe it, it's like the sound of something heavy and made of metal clunking around inside a trunk.

Jacked it up via the diff and took both rear wheels off, both sides look identical. Checked bearing play on both sides, made sure nothing was loose. I get equal travel and rebound on both sides when I put my weight on either corner. Granted, I haven't had the car up on jackstands so there's always been load on the diff, but I can't find anything wrong. Don't want to start replacing things here and there in hopes of fixing the sound until I get the rest of my suspension ready to go for the track next spring. The only thing I can think of that may be the cause is that I've got a slow leak on the tire on that wheel. Oh, also my car is tracking straight and both sides look identical when it's sitting on the ground.

Any ideas?

 

Did you check the strut mount?

 

Check for a bad front diff mount.

 

I did check the strut mount, pulled my speaker out of the pillar even :p Everything looks fine, even torqued down correctly.

Thanks!


You mean see if the bushing has worn out? Or do you think it could have actually cracked the mount?

 

You could have cracked the front diff mount, this would cause the diff to lift up and smack the underside of your car.

 

Check your exhaust. Mine makes that same sound, and after checking all suspension pieces I wiggled my exhaust around and that was the source.