Flush the radiator in your 2020-2023 Chevy/GMC 6.6L L5P Duramax with the correct Coolant & Additives. You'll find full synthetic and conventional antifreeze with supplemental additives that offer 150,000 to 750,000-mile service life. Offering corrosion prevention, faster warm-ups, and reduced engine temperatures, these additives will help to minimize surface tension for more efficient cooling. XDP carries Mishimoto, Evans, Hot Shot's Secret, XDP, Lucas Oil, DEI, Royal Purple and more.