Stock is never good enough and Kooks y-pipes offer freedom from the restrictive factory pipes on your ride. Kooks y-pipes are made of TIG welded, beautifully crafted 18 Gauge 304 Stainless Steel, these y-pipes offer better exhaust flow with improved horsepower, torque, and throttle response, plus a deeper tone. Adding aftermarket exhaust is a good way to boost your driving experience and Kooks can help. This y-pipe is designed for 2003-2008 GM V8 Trucks with the 5.3L or 6.0L engine only.