I have this rattle sound from my tahoe that sounds like a heat shield rattle but it isnt. I cant find the cause of this DAM noise. I was thinking something in the muffler but im not sure. It only does it when stopped and idling. Anyone else come across this issue?

 

It could be one of the baffles in the muffler that has come loose. Not uncommon.

But there could be a heat shield near the cats or by the spare.

 

it sounds like a heat shield I have had them do this before. you could jack it up and get under there when it is idling and see if you can find it. (it's going to be warm under there) but that would be the best way to find the problem.

 

Be sure you use jack stands if you do. It's tuff to bench press a truck.

 

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thats a good reminder for alot of people. I have always used them. A guy 2 blocks away from me died 2 years ago from the jack giving out while he was under there. The t-case came down on his head with rest of the truck. It was a s-10 zr I think.