I was thinking of changing the muffler on my 1500hd, it uses the same piping from the 1500 except for duals all the way back to the muffler and 3in pipe to the cats. The tail pipe however is only 2 1/2, I want to keep the same one exit but was wondering if I should try to get a bigger tail pipe? As the 2500hd have a 3 1/2. Would I see any mpg/power gains if I where to change out the muffler and tailpipe or should I do just a muffler? Thanks!

 

You can kill your motor doing that. You MUST replace it with OEM.

Only an ENGINEER can "change the muffler" because it effects many components that can cause engine total failure: such as the exaust valves and catalytic converter.

some will say "a muffler expert can do it", but in reality you will likely find 0 muffler expert shops in your town (ie i do NOT mean speedy muffler shop!!!)

 

let's say this another way: a muffler with a good dent fails inspection. why isn't because it's a safety issue. why is really a "green" issue. it's such a waste to kill a motor over refusing to replace a muffler with a loose part inside that (in my state) "it's simply not allowed to do it"

 

a muffler is not a safety issue and won’t kill a motor without one. And a muffler does nothing to exhaust gasses other than quiet them. The cat is what cleans it.

 

would not do any damage at all. a 6.0 1500hd run the same engine trans and chassis as a 2500hd.