Buzzing in Cat

[Chuckster]

Cat Converter on my '04 SD is buzzing at idle when warm. If I get under the truck and hit it with a hammer the noise goes away for a couple of days. Noise also stops if you put foot on exaust tip. Anyone have any experiance with this????? Neighbor suggested Ford had a run on bad converters for a while...??

 

[DaveBen]

Interesting. My CAT has about the same miles and time on it, and no problem with the buzzing, or rattling.

Dave

 

[KRISTOLSON]

My dad's '04 gas has a similar problem, but on his it is the heat shields that make the noise. He says they are mounted with spotwelds that have popped loose, so he has a lot of hose clamps holding the shields tight.

 

[BIG JOE]

My dad's '04 gas has a similar problem, but on his it is the heat shields that make the noise. He says they are mounted with spotwelds that have popped loose, so he has a lot of hose clamps holding the shields tight.

X2.

The fact that when you put yer foot on the tailpipe.. or hammered it.. it quit.. made me think [heat shields] too ?

 

[Chuckster]

Thanks for the replies... I'll have to get under there again and look but it's my gut feeling that the insides of the cat are coming apart. I'll try wrapping it with a hose clamp and see if that changes the resonance at all.

 

[Chuckster]

Well the problem turned out to be what I suspected... The internals of the Cat came apart and were shaking themselves to death. Nothing a By pass pipe didn't fix. Tore out cat and put the by pass pipe in it's place. Exhaust note is a little more pronounced and more desireable... YAY:

 

[DaveBen]

KEEP the CAT! Some day you will need it.

Dave