Paid to have a Cherry Bomb Pro 40 series muffler and 3 inch pipe on my truck. I kept the single dump with the stock resinator. Man did the truck drone. It was so bad the back window sounded like it was going to come out. I replaced it today with a magnaflow and the truck sound great. i would not recomend the Cherry Bomb pro to anyone on the 4.7. You will cover your ears at 1700 rpm. Just my two cents.