I have the Flowmaster direct fit # 717847. Super easy install at home in the driveway. Sounds awesome on startup, idle, and hard acceleration. As long as your in 8 cylinder mode it's perfect. A few notches louder than stock but much more bass and growl which I love. Zero rasp. However.... it sounds like a sick Hippo with major gas when the truck goes into 4 cylinder mode though. There is a reason why the stock muffler is the size of a 55 gallon drum...and that is to take care of the funky frequencies when in 4 cylinder mode. On the interstate 4 cylinder mode is fairly quiet. However, low speed low rpm cruising in town when it drops to 4 cylinder mode is annoying. Sometimes I'll just cancel it out by pushing the "tow/haul" mode button to run it in 8 cylinder mode. Would I go back to stock? No way. Other than 4 cylinder mode it's sounds great.
