I have dual exhaust, 2 flowmasters on their side and 2 tailpipes exiting on each side of the hitch assembly. Sounds good, kinda loud, but not bad. If I were to do it again, and I may, I would go with a large diameter single set up. I had to move my spare tire back and up, move the tube that goes to the tire lowering device, and I have continuing problems of the exhaust coming loose. The whole system from front to back is too stiff, I either break hangers or the manifold collector nuts come loose. The system has been on the truck for about 6 years, and now that the Flowmasters have started to crack and come apart, I am thinking of changing it out. I think I can get the same power output with a single 4" muffler and tailpipe.