Flush the radiator in your 2006-2007 Chevy/GMC 6.6L LLY/LBZ Duramax with the correct Coolant & Additives. Full synthetic and conventional antifreeze with supplementary ingredients provide you with a service life from 150,000 and 750,000 miles. In addition to reducing surface tension for more effective cooling, these additives also offer faster warm-up times, corrosion prevention, and lower engine temperatures. Evans, Hot Shot's Secret, XDP, Lucas Oil, DEI, Royal Purple, and Mishimoto are just some of the top manufacturers available at XDP.