Keep the engine and fuel system in your 2003-2010 Chevy/GMC Kodiak/TopKick 6.6L Duramax clean with Fuel Additive. Some additives enhance fuel system performance, while others are made specifically for cold weather and to reduce fuel gelling in winter temperatures. Most additives are specially formulated to help clean engine and fuel system components, reduce smoke, and help to improve performance. Find the additives you need in your vehicle from the top brands like FPPF, Hot Shot's Secret, Lucas Oil, XDP, and more!