Replace or upgrade the exhaust system on your 2011-2016 Chevy/GMC 6.6L LML Duramax with a new downpipe. Aftermarket downpipes offer smooth mandrel bends and larger diameter tubing for an increase in horsepower and torque and can help your lower exhaust gas temperatures (EGT's). The factory OE downpipe typically incorporates unnecessary bends or crimps in the tubing restricting exhaust flow. You can find all the top brands including AFE, AP Emissions Technologies, Banks Power, BD-Power, Dorman, Fleece, PPE, Magnaflow, MBRP, and more!