I test drove a 00z28 a couple of days back, and it has a rattle towards the rear right side of the car when in reverse and sometimes when in drive at certain rpms. I asked the guy about it and he said that the exhaust needs to be tightened. Is this correct? I havent had the opportunity to go under the car and check it out myself. I think that this might be true because on my 96 z28 i also have the same kind of rattle when in reverse. Has anyone experienced this problem before?