i have a 03 3500 i have no muffler and 5" stacks but does not sound as good as my buddies 02 with same is there any muffler out there to help?
also is there any way to put bigger blow off value

 

it's not going to sound as good, period. Yours is a 3rd gen and his is a 2nd gen. They just don't sound as good due to the common rail injection and some other changes.

I just added a magnaflow 4'' straight through muffler on mine though and it sounds a WHOLE lot better than before.

Another thing you can do.............I added an AFE stage 2 air intake and it sounds like a Jet engine taking off. The turbo spooling sound is music to my ears. (for now anyway)

 

thanks i will see if that helps