More than likely, it is your shock mounts. If you have an after market sport supspension, then replace them with shock mounts from an after market out fit such as JT Designs. They cost more than stock but are worth it. Check out their web site at www.jt-designs.com. If you are a do-it-yourselfer, then visit the tech section of www.racepad.com. I had mine done last week and it was not hard at all. Took me about 2 and a half hours to do both rear mounts. Just make sure you have your car sitting on a couple of jacks and a friend to help out. Hope this helps.