Lately I have been hearing a rattling sound when my rear hits a bump. So today I put my car on ramps and checked underneath. All seemed nice and tight, what I did find is that if I hit both exhaust canisters they sound as if there are small pieces of metal in there. It's the same sound I hear when I go over bumps or pot holes. I'm guessing this is not normal? Any Ideas?

 

I have 2 ideas. Either the baffles have broken inside the muffler. Or you are hearing pieces of the melted cat converter.
Good Luck.

 

That's about it in a nutshell.

 

I would actually rather have the CAT be the problem because it is still under warranty. The MS exhaust is now out of warranty since I've drove 14K miles since it was installed in Nov. of 2006. If it's the CAT I know I should definitely get it fixed. If it's the baffles of the mufflers is their any negative side affects? Thanks in advance.

 

I would actually rather have the CAT be the problem because it is still under warranty. The MS exhaust is now out of warranty since I've drove 14K miles since it was installed in Nov. of 2006. If it's the CAT I know I should definitely get it fixed. Anyone have an answer?