Exhaust question for 2500 owners

[bigdog9191999]

This is what the oem muffler looks like on both ( this one specifically is our Denali. A tape measure or calipers would tell the size of the stock pipe easy enough, ( pretty sure the Denali was 3" and the 8.1 3 1/2., Would be minimum of this Evening that I could find out. )

 

[bigdog9191999]

This is what is on the Denali now, my avalanche had an actual dual in muffler , but the exit looked basically the same as hers.

 

[rockola1971]

RA was the first we checked. Besides a Walker/DynoMax system, all they have is OEM replacement mufflers from AP. They showed dual 3" inlets and a single 3.5" outlet. The "local" parts stores don't document anything for the 8.1.

I think he ordered a muffler that was supposed to be an OEM replacement and it had dual inlets and outlets. He doesn't care so much about the configuration. He just doesn't wanna put a system designed for a 6.0 on his 8.1 if it's not the same. We can't figure out why someone would remove the entire system from after the cats unless they wanted the large size for a performance build. At least they left the cats!

He's in Kansas so I'm helping remotely. He's stays really busy being self-employed, so updates from him are slow.

They sure dont show anything but GMpartsdirect.com shows 6.0L and 8.1L same exhaust part numbers for front pipe and catalytic converter. It appears there was a 1st and 2nd design.

Exhaust Components for 2002 Chevrolet Avalanche 2500 | GMPartsDirect.com

www.gmpartsdirect.com

 

[1badjimmy]

That is what came in my 8.1 Burb. The inlets are necked down to under 3”OD. The exits are 3” OD. The tailpipe exit is 3” OD as well.

The muffler is 25” long X 12” wide.

 

[iamdub]

This is what the oem muffler looks like on both ( this one specifically is our Denali. A tape measure or calipers would tell the size of the stock pipe easy enough, ( pretty sure the Denali was 3" and the 8.1 3 1/2., Would be minimum of this Evening that I could find out. )


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That is what came in my 8.1 Burb. The inlets are necked down to under 3”OD. The exits are 3” OD. The tailpipe exit is 3” OD as well.

The muffler is 25” long X 12” wide.

Excellent! This is what I needed to see. Now we know what to look for since we can't trust what's listed in online specs.

Thanks, guys!

 

[iamdub]

They sure dont show anything but GMpartsdirect.com shows 6.0L and 8.1L same exhaust part numbers for front pipe and catalytic converter.

And that's all of what he still has. Something else to note is that if the exhaust forward of the muffler will support an 8.1, then it's plenty sufficient for even a warmed-over 6.0.

It appears there was a 1st and 2nd design.

Exhaust Components for 2002 Chevrolet Avalanche 2500 | GMPartsDirect.com

www.gmpartsdirect.com

I just thought of something- I wonder if there are California emissions and non-CA emissions versions. Between this link and the pics the others posted, I believe we can get the correct parts.

Thank you!

 

[1badjimmy]

Excellent! This is what I needed to see. Now we know what to look for since we can't trust what's listed in online specs.

Thanks, guys!

If your buddy wasn’t in Kansas I’d say come get this stuff. My Suburban is getting swapped to a Duramax = won’t need this stuff.

 

[iamdub]

If your buddy wasn’t in Kansas I’d say come get this stuff. My Suburban is getting swapped to a Duramax = won’t need this stuff.

Bad ass! You doing the work?

Curious, though- where are you located?

 

[swathdiver]

Chris, did you go to Walker Dynomax's website and see if that Avy is listed?

 

[Fless]

Chris, did you go to Walker Dynomax's website and see if that Avy is listed?

Good thought, but they list only the 1500: