exhaust system vibration?

Dave Z66 · May 8, 2006

I have a stock 2003 C2500 HD crew cab long bed with the 6.0 and have recently started noticing a sonic vibration at 1200 rpm and again at 2200 rpm. It's a metallic vibration that sounds like it is coming from the tail end of the exhaust system. I have checked all of the exhaust hangers and have searched for anything loose for metal to metal rubbing. It's really noticeable in a parking garage when the motor reaches 1100-1200 RPM. At first I thought it was the fuel line touching the frame after installing a new fuel filter but that checked out ok. I also suspected that maybe a brake line might be the culprit but that all seems fine too. I now have approximately 94,000 miles with no other problems but it's out of warranty. Any ideas other than taking it to the dealer??

Supercop8100 · May 8, 2006

Its either a baffle in one of the mufflers or the heat shield on one of the cats. The heat shield is an easy fix, if its a muffler it will have to be replaced.

Bumblebee-tuna.

dewfpo · May 8, 2006

Have you checked for missing bolts on all the heat shields, exhaust shields especially. There are several on the truck. They are thin gauged metal and tend to vibrate easily.

DEWFPO

Draenor · May 8, 2006

Sometimes I get rocks in between the heat shields, they can drive you nuts. I would check to see if they securely attached.

ctryboy60 · May 8, 2006

Could be the insides of the catalytic conv. have broken loose and are rattling

Dave Z66 · May 9, 2006

Well, after closer inspection and banging on the system with my hands, the vibration is coming from the heat sheild on top of the muffler. The sheild appears to be tack welded to sides of the muffler and I cannot see where any welds have separated. I am sure this vibration is pretty common. Anybody with a good do it your self fix?? I sure would hate to have to remove the muffler but will do so if that's what it takes. Thanks for all the great replies! This site is the best.

gmbellew · May 9, 2006

Well, after closer inspection and banging on the system with my hands, the vibration is coming from the heat sheild on top of the muffler. The sheild appears to be tack welded to sides of the muffler and I cannot see where any welds have separated. I am sure this vibration is pretty common. Anybody with a good do it your self fix?? I sure would hate to have to remove the muffler but will do so if that's what it takes. Thanks for all the great replies! This site is the best.

<{POST_SNAPBACK}>

ask the dealer about some dampeners that hang off the exhaust to stop vibration. i had a similiar exhaust vibration on my 04 suburban (5.3L). if you do a search, you should come up with my story.

Dave Z66 · May 9, 2006

Thanks so much for the advice. I had no idea that they make a dampner specifically for this problem. I will get by the dealer to get one of these. In the mean time I thought about something that i could wedge in between the muffler and heat shield that would not catch on fire....and don't laugh! ...but I figured that a wadded up ball of tin foil would do the trick until I can get by the dealer.