I have owned 5 thirdgens (87IROC, 90IROC, 2x91Z28, and a 92RS) and all 5 have not only rattled, but have also had horrible clunking when going over bumps. The clunking seems to be mostly in the rear, but sometimes comes from the front as well.

I've done some searching but not found exactly what I need.

I'm sure that the clunking is a result of suspension components, like panhard, LCAs, springs, etc, but in my case, I've checked most everything out and am still coming up confused.

My panhard and LCAs were boxed at some point and poly bushings were installed in all 3 parts. I was hoping that the typical clunk was attributed to a bushing, but in my case, that doesn't seem to be true. My motor/trans mounts are newer and the torque arm is tight on the axle and a new poly bushing was installed a month ago.

My thirdgens have ranged in mileage from 70k-160k and all 5 have had the same type of clunking.

The front has nice tight tierod ends and everything suspension-wise (sway bar bushings, spindle to strut bolts) are nice and tight.

I've been thinking about replacing my shocks/struts as they are probably gone due to age, but want to know what else might be suggested in addition to those to help reduce the noise.

Before anyone says SFCs, I will get some at some point, but there is another reason for the noises I'm hearing other than just simple chassis flex.

Any help would be great.

 

I was experiencing a clunk for quite some time and it actually turned out to be the hatch latch. It always felt solid when closing but finally I went over a speed bump near a house where someone was mowing the lawn and the mower sounded briefly louder just before the clunk which made me decide to pull up on the while closed and sure enough if I pulled hard enough it would move. tightened the bolts and haven't heard it since.

 

I believe my hatch latch has the same problem, was gonna check it out this week.... Everything else is replaced w/ higher quality parts/bushings, including struts/shocks....

 

shocks can get noisy when they age, especially when the stock rubber bushings start to rot.