I noticed this noise after I installed the Downey Coils and Bilstein shocks in the rear. (had Revtek prior to this setup - and no noise) It is a booming type sound - as if the tire were dropping to full droop with a boom - yet It happend over small bumps too - So I'm fairly confident it'd not the shock reaching it's full extension, but maybe. Just tonight I drove over one of those little parking lot cement curb things (with just the passenger side tires) and as my right rear tire crested and started to decend I heard it --"boom" and then followed by the "boom" of the tire actually hitting the ground. So I know it's not just the tire noise - there are 2 booms. One as the tire decends and one when it contacts the ground.

Any ideas?

John