I have a 00 camaro ss. Today it sounded like a bunch of aluminum cans rattling around under the engine. It is a T56 and I wouldn't be surprised if it were transmission related as i know it has problems (i.e. syncros worn and grinding in third gear.) It only rattles loudly when the car is first started. It happens whether the a/c is on or not.

I looked in the engine bay and couldn't see anything that would be causing the rattle. It also sounds as if it were coming from under the car and not from the engine bay. Any ideass?

 

Maybe your Cats are toast?

 

haha why didn't I think of that? Good call. Is there anyway I could test that?

 

jack it up and hit it with a rubber mallet.

 

Maybe it's time to cut those off. The car has 105k so I wouldn't doubt they're fried.