In the search for additional power, the restrictive factory downpipes should be high up on your list to replace and upgrade on your 2011-2016 GM 6.6L Duramax. Our selection of downpipe kits is an easy way to give your 2500HD/3500HD GM Truck an aggressive exhaust note while improving its power, torque, and fuel economy along the way. These kits also help slightly drop EGTs to help maintain controllable temperatures on your truck without compromise. Choose from the entire selection of downpipes to get the exact look and sound your tough GM truck and start showing off your performance mods with confidence. Pair your high-performing downpipe with our selection of Single-Exit Exhaust or Dual-Exit Exhaust.GM Duramax Fitments: 2011, 2012, 2013, 2014, 2015, 2016 GM 6.6L Duramax.Submodel Fitments: WT, Custom, LT, LTZ, High Country, 1LT, 2LT, Pro, SLE, SLT, AT4, Denali.Some exceptions apply, please see individual product pages for specific fitments.