Ordered the Dynomax VT 3" in and out single center/ Center 17962 muffler from Summit today. I'm going back to a single tail pipe for a change and see if this VT series helps with the cab noise. Been running a Magnaflow 3" in and duel 2.5 out for about 120,000 miles.
3500 Megacab 4x4 4:10 Gears
Laramie 6.7L Asin Trans
I have a 40 Series Flowmaster single in, dual out on mine back when I had a 3.7 Sounded really good... so good, I had SRT10 guys turning heads. Only draw back, it had a drone like you wouldn't believe.