2009 Gmc Sierra 6.2l Exhaust Flex Pipe Issues

Davidg159 · November 18, 2009

2009 gmc Sierra 6.2L

I have been hearing strange sounds coming from, what I have isolated to, the flexpipe in the exhaust system. It sounds like the accordian pipe and the external metal mesh are rubbing at certain rpms, creating this "sheen" like sound. Like two very lite metals rubbing together. This sound happens most often in 6th gear, just as I pass through 40mph. As I let off the gas and lose the tension of the engine and let it fall back through 40mph it becomes very apparent. I don't completely let off the gas so it isn't caused by the road surface, it is more based on subtle vibration or harmonics of the engine.

I took it to a muffler shop and they told me these flex pipes are junk and I should remove it or I will have to in the future anyway.

I understand these have been designed to minimize the jolt to the exhaust manifolds lessoning the likely hood of cracks and malfunctions.

Can I get away with cutting it out and replacing it with straight pipe? Or will I really have problems? And will removing this create warranty issues.

Does anyone have any advice?

Nytemare · November 18, 2009

Definitely will cause a warranty issue.

Take it to the dealer and have them look at it man.

It could be a defective piece.

Davidg159 · November 18, 2009

Definitely will cause a warranty issue.

Take it to the dealer and have them look at it man.

It could be a defective piece.

I installed an aero muffler recently but kept all the stock exhaust components. We cut the oem muffler out and welded in the aero. Now, the angle of the pipe might have changed ever so slightly but I am talking tiny, if any. Also all the hangers a vertical so there is no additional length or reduction of length that would compress or extend the accordian. I figured the flex would be forgiving of any subtle changes.

Sorry I didn't mention this in the first post, got tired of punching keys on this phone.