Shop Aftermarket Exhaust Systems and upgrade your 2006-2007 Chevy/GMC 6.6L LLY/LBZ Duramax. Exhaust systems are typically available in stainless or aluminized steel and are available in a wide range of diameters and styles. A performance exhaust kit will typically add horsepower/torque, decrease the exhaust gas temperatures (EGT's), and can even help engine efficiency. Different diameter exhausts are available such as 4" & 5" and offer unique sounds for your vehicle. Exhaust installation is normally a do-it-yourself project that can be completed in your driveway. You can find all the top exhaust brands such as MBRP, Magnaflow, AFE, Banks Power, AP Emission Technologies and more!