OEM mufflers?!

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stutaeng

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Hey guys, I hope someone can help me. I've got a GMT800 2500 Suburban with the 6.0. The P.O. installed some Flowmasters. The muffler has 2 inlets and 2 outlets. It sounds kinda cool, but it's driving me nuts!

I'm used to factory sound. Does anyone know where I can find the factory muffler? Rockauto for some reason does not have this muffler listed? Are they like generic? I admittedly know know nothing about mufflers, LOL. X, Y, true duals? I'm clueless, just want to get factory sounding truck.

Also, do those clamps work well? What I'm asking is can I cut it off and put some extensions with clamps? I can weld and have a MIG setup, just don't know that I feel comfortable welding down there? Are the clamps durable?
 

Supercharged111

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Hey guys, I hope someone can help me. I've got a GMT800 2500 Suburban with the 6.0. The P.O. installed some Flowmasters. The muffler has 2 inlets and 2 outlets. It sounds kinda cool, but it's driving me nuts!

I'm used to factory sound. Does anyone know where I can find the factory muffler? Rockauto for some reason does not have this muffler listed? Are they like generic? I admittedly know know nothing about mufflers, LOL. X, Y, true duals? I'm clueless, just want to get factory sounding truck.

Also, do those clamps work well? What I'm asking is can I cut it off and put some extensions with clamps? I can weld and have a MIG setup, just don't know that I feel comfortable welding down there? Are the clamps durable?

You live in TX where stuff doesn't rust, I'd hit the junkyards.
 

stutaeng

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I've been driving it like that for now. The only place that I found the stock muffler was GM parts direct for a whopping $1,200. Rockauto, local parts stores don't list them, not sure why?

On my V6 Silverado the muffler rusted out at the connection and I took it to a shop to get a new one. I never asked about loudness and they never mentioned anything...well, the new one was a bit louder. Not much to complain, but just a bit louder.

I bought another suburban as a project, same as the one I'm talking about with 6.0, but a 4x4 and that one has stock muffler. Whisper quite. I like it...I haven't seen if I can swap them.

The 2500 suburbans apparently have a different exhaust than 1500s, so they are not as abundant at the junkyards. I haven't seen any 2500s at the local yards the last several times I've been out there. I did find one with 8.1 engine, but was about an hour's drive...for $200.

But need to do something, as this vehicle is going to be my wife's daily driver soon...
 
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Schurkey

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OEM muffler is probably stainless steel. Very durable.

Aftermarket mufflers are most-likely "aluminized steel". Lucky to get ten years out of them.

There are some stainless steel aftermarket mufflers. Not as expensive as OEM, but certainly more than the aluminized stuff.

For the record...the OEM mufflers are quiet, but also restrictive.
 

stutaeng

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OEM muffler is probably stainless steel. Very durable.

Aftermarket mufflers are most-likely "aluminized steel". Lucky to get ten years out of them.

There are some stainless steel aftermarket mufflers. Not as expensive as OEM, but certainly more than the aluminized stuff.

For the record...the OEM mufflers are quiet, but also restrictive.

I wondered why the aftermarket stuff didn't last long. This loud muffler was added by the PO and the welds look like pigeon poop... LOL

Do you think it may make a difference on a completely stock engine as far as restriction?
 

kennythewelder

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I wondered why the aftermarket stuff didn't last long. This loud muffler was added by the PO and the welds look like pigeon poop... LOL

Do you think it may make a difference on a completely stock engine as far as restriction?
The reason the mufflers dont last, and the welds look like poop, is because the mufflers are built in China, or another country like that. The metal is inferior as is the welding. As for a power difference, yes. Doing a less restrictive exhaust system will not only help with power, but will also give better MPHs. One of the things that help with cab exhaust noise is to run the exhaust out of the back of the truck, but if you go with an OE replacement muffler, this wont matter. OE mufflers are made from steel but are coated to prevent rust. They are a good quality steel that has a good coating over. They are NOT stainless steel. There are a lot of different grades of stainless steel. The better the grade, the more expensive it is. When I did my exhaust work, I got rid of the OE muffler first, and replaced that with 2 old school glass packs, 24 inches long, and ran true dual exhaust out of the back. I gained power and a little MPG. I then did shorty headers. I lost MPGs because I have a lead foot and like the power. Then I gutted the cats, and built 2 cat simulators. I gained the MPGs back that I lost with the headers, and even more power. Everyone likes the way my truck sounds. Its not real loud in the cab, and doesnt really have a drone at HWY speeds. It is only loud from behind the truck, and then really only when I nail the gas peddle. But what I like may not be what you like.
 
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