Long ago and far away, my "clunks" were due to delaminated trailing arm bushings. The bushings tie the trailing arms to the frame and are designed with a rubber bushing inside a steel sleeve. The rubber and steel became loose and, during an acceleration ie deacceleration transient would clunk. I replaced twice with stock parts during the first 9,000 miles. The second pair failed shortly after installation and I have not driven the car since. Fred 6894 (now at DMC Houston)