Find the Coolant & Additives you need when servicing the cooling system in your 2001-2004 Chevy/GMC 6.6L LB7 Duramax. You can find engine coolant and additives that offer 150,000 to 750,000-mile service life. In addition to reducing surface tension for more effective cooling, these additives also offer faster warm-up times, corrosion prevention, and lower engine temperatures. Top manufactures like DEI, Royal Purple, Mishimoto, Evans, Hot Shot's Secret, XDP, and Lucas Oil are offered by XDP.