So I put my BB exhaust on my ext a couple of weeks ago and after doing so I get this heat shield rattle on start up and initial acceleration (its just at one low rpm). It is not the rear spare tire shield bc I removed those two bolts that hold it on and took it off the truck to check and it still made the noise. Im assuming that it is the under body heat shield then.
I was wondering if ne one else on here with aftermarket exhaust is having or had the same problem and how did you rectify it? My buddy that works for GM at the proving ground said that he has the same issue on his 07 avalanche with a corsa system. Any help or insite is appreciated.