Reviewed By charles t (FOUR OAKS, NC) Reviewed for a 2014 GMC Sierra —4/15/2015 8:59 AM
Muffler sounds great when added with a k&n 77 air intake. Just remember new sierras and silverados, need to have the exhaust adaptive valve locked in full open position for full effect. Spring loaded valve damper inside pipe 6 inches after factory muffler. There to keep down sound when in v4. Does not effect performance of vehicle. Also remove the resonator. Worth the investment!!!!