No...i ditched my cat and it got worse....the Hushpower by Flowmaster is really good. I have ridden in a few trucks with them and it sounds great. They were all 4" turbo back kits, with the Hushpower as well. James at Rollin Smoke Diesel is knowledgable on the issue, and has a few products that can help.
Rollin' Smoke Diesel - Cummins Diesel Perfomance Parts
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Cowboy Cadillac 2007 Dodge 3500 DRW QC 4x4; 6-speed, RanchHands, 4" TBE w/ 6" Tip. AFE stage2, Silencer ring MIA