So last week I swapped factory springs out for NM Eng. lowering springs. I did nothing else. Have not even gotten an alignment yet. During test drive, there is a clunk on both sides of the rear end as I go over imperfections in road. After checking torques and even tightening above torque another test drive showed the clunk was still there.

Then, after disassembling the rear end again, then rebuilding, the clunk is still there... UGH!

After searching around, the best I found was possibly sway bar or rear links on this thread.

I have not reinspected the car yet, but looking to NAM folks that might have some insight.

The clunk issue was not there the minute before the spring swap.

Edit: this is for an '08 MCS non sport suspension. The struts do say "S" though.

 

i too would be interested in this since I'm also experiencing the same problem

 

Over 80 views and no suggestions...

However, I've not had the chance to check on anything mentioned in the link to the thread I posted above.

 

A clunk really is kind of a broad term. Does it sound like it is coming from the suspension or the body? Is it all 4 or is it just a corner? Most likely it is probably bouncing of the bump stops. Though I don't have this problem with mine.

 

I know it's hard to describe, but it is coming from the suspension. The best way to describe it is as though none of the bolts are tightened and there is rattle/clunk. I know that is not the case though. I have ruled out bump stops as the sounds come from imperfections that would not allow the suspension to travel at all. It is not on all 4 corners, just the rears.