I have an 02 and have reprogramed with a Hypertech. Since I use the stage 3 exclusively (95 hp increase setting), I put a Summit 4" exhaust system on it. It resonated in the cab so horribly I had to put a Donaldson muffler on the size of garbage can. Still frustrated with terrible sound resonating in the cab I had an MBRP 4" system installed. Now I'm worse off and $600 poorer. How the heck do you get rid of horrible resonating sound in the cab. I don't want it to sound like a honda, but I'd like to be able to hear my radio. I'd also like to avoid going back to stock.