i got a 2002 Z28, and i have been having a gringing sound come and go from my rear driver side wheel well. I took it into the shop and the greased the bushings. The noise came back a few weeks later and I took it in again to the chevy dealer and they called their support line and they greased up the bushings again. Now a few week later, again, the noise is back and its more irratating than anything, it sounds off on big bumps. Just wondering if anyone else has run into this problem???