Here's an interesting one: If I am driving over a somewhat rough road at 65 MPH, my car will vibrate excessively from the rear of the car, but it does stop once the road is smooth again. Going over R/R tracks gives me a hollow thump sound also. It seems that I may have bad shock absorbers in the rear of the suspension system. Although I cannot get any results by doing the "bounce test" by applying pressure to the back end of the car, a different story unfolds while driving. Have any of you members experienced similar effects on your car? Did replacing the rear shock absorbers solve the problem? Let me know! Thanks. JM>