Correct Exhaust Flange Gasket Part Number?

[73LeMans]

Hey guys - looking to see if anyone can identify and supply the correct part number for the triangular type gasket that goes between the header and the exhaust pipe for a 2003 2500HD 4WD Sierra with the 6.OL gas engine. Every site I look for parts lists an O ring gasket as the correct gasket, but its not an O ring. Its not even close...what I need is triangular in shape has three bolts that hold it in place, and is made of a thick metal/fiber type material.

 

I got one part from NAPA, but the distance between the bolt centers is 3.1" and thats too short. The gasket I'm looking for has the distance between two bolt centers at 3.1", but the distance to the third bolt from both of those needs to be 4.5". Anyone know what Im talking about? None of the parts stores around here seem to...

 

All of the truck is stock except for the BBK headers...however, BBK had no problems sending me the right gasket with the headers to bolt up to my stock exhaust, so there is nothing different about the headers that would cause parts locating to be difficult. I just cant get a part number of that gasket to get another one or even cross reference.

 

I havent called GM yet, mainly because I didnt think I had to, but being this late, I thought Id check here first to see if anyone could help with a parts id number. I searched the 2500HD forums and found nothing...

 

Thanks.

 

~Mark

[73LeMans]

Talked to a parts guy @ GM about this and it was interesting. Hes a good guy - been doing it 30 years so I give his ability some weight.

 

Dealer says they don't list a gasket for that side (drivers) of the truck. Based on the crappy picture he had in the books of a Silverado/Avalanche 6.0L, he sees a triangular type flange on the drivers side only, but no gasket listed as going in there. Not even a donut type gasket. Hmm... Makes me wish I didnt farm out the header job to a friend, as now I have no idea if it had a gasket to begin with. I got a gasket with the headers so I just assumed it would go back in. Maybe sticking it all back together with no gasket will work and stop the leak. I'll give it a shot and let the board know.

 

It would explain why I seem to have such a hard time finding one.

 

If that fails, I found some gaskets on the NAPA web site that might work...just have to get them to let me handle the part so I can do some measurements. And at the very worst, I could make a gasket, but since its exhaust, I dont expect and gasket "paper" to stand up to the heat.

[73LeMans]

NAPA gaskets didnt come in yet, and I got tired of waiting. Made my own out of the cool gasket material sheets they sell. Has the metal core and everything. Works great now.