I have a 5" straight pipe made by expandit, that I got from Rollin smoke diesel. The kit installed pretty well and it sounds awesome, I like it alot better than the 4" I had on my truck before. A friend of mine use to sell aftermarket parts for CTDs and the exhaust he sold was also mae by expandit and he sold alot of them. Never had any complaints about the kit, the only issue he had was the a few kits were beat up when he recieved them, the shipper must have thrown them around on the truck cause a few of the pipes were dented or bent and the boxes were really beat up.