Keep the cooling system in your 2004.5-2005 Chevy/GMC 6.6L LLY Duramax functioning properly with a high-quality replacement water pump. Get replacement water pumps from leading brands including Dayco, Alliant Power, Bullet Proof Diesel, Bostech, Diamond Advantage and many more! The factory water pump on your truck can lose efficiency over time from corrosion, failed pulleys, or leaking gaskets. Replace or service your water pump to ensure that your engine's cooling system is functioning properly. Shop XDP today and find the water pump you need.