I just bought my 06 gto with 63 miles and noticed knocking from the motor and a clunk from trans or rear end. What the heck I traded my 01 2500Hd with the 8.1 piston slap vortec for an 06 6.0 ls2 rod knocker. I regret getting the diesel goat and just want my piston slappin truck back. And the dealer said this is no big deal and they cant get me in for almost two weeks and its ok to drive because theres nothin wrong and if there is it would just be an exhaust leak. Now I have 530 miles on it and noticed that the knocking can be heard from both front wheel wells and usually begins knocking about 30 seconds after start up. IF it was an exhaust leak both headers must leak and find this hard to believe. I bet somebody had there foot sar far in the motor it was sticking out the grill. Has anybody had such issues with there gto? OH ya forgot to mention the clunk that happens when i shift my 6 speed