Hello all, recently discovered my OEM exhaust rusted and broke between the 3rd cat and flex pipe on my NNBS 6.2L. What I have found is there is no replacement parts made for the 3.5" exhaust of the 6.2L. For example the clamp at the ball flange is totally rusted, is this a special clamp or just a band clamp? I have only found the OEM part as replacement. Also is it totally necessary to have a flex pipe, most aftermarket cat backs don't have one. I find most shops only have either 3" or 4" universal flex pipes as replacement. I have also thought to just buy the MBRP S5070AL cat back for $450 CAD and replace everything, but unsure how long the aluminized system will last in winter. I plan to drive this truck a few more years and wouldn't mind some extra performance and sound. It's stock other than a CAI.

 

Find another OEM exhaust to replace it with or get a full 304 stainless steel exhaust, the 4xx grade stainless and aluminized steel will only last a few years

 

I'll probably never find a used OEM exhaust here. I had to order my truck to get a 6.2 LTZ, I would guess maybe 5% of 11-13 GMT900s here in Canada had the 6.2. In the 12 years of owning mine I rarely see other trucks with the tailpipe out under the bumper.

 

Canadian winters can be hard on all trucks. Look into something like a Magnaflow cat back replacement kit. I am sure other companies also have a stainless kit and a warranty

Other wise visit a muffler shop and let them repair it...

 

GM 22812180 assuming a 143.5 Crew Cab wheelbase.

 

Is there anything special about the GM clamp? I doubt I can get mine off without cutting it. I can find regular 3.5" band clamps for much less.

https://www.gmpartsgiant.com/parts/g...-20779890.html

The truck is so I'd rather not spend $1k on the Magnaflow or a new OEM system, but I feel like a shop is going to bend me over to repair it due to the uncommon pipe size.

 

It is a type of ball and flange socket. The clamp is rounded so it seals around the joint. I'm sure you can find it on amazon or summit or your local auto parts store...

 

OK I think I have found a head pipe for a 14-18 6.2 truck from a Corsa cat back system. Looking at pictures I think it is similar enough to make work if I can get it.