For 2001-2005 GMC Sierra 2500 HD 3500 6.6L Duramax LB7/LLY. For 2001-2005 Chevrolet Silverado 2500 HD 3500 6.6L Duramax LB7/LLY. This coolant hose "T" fittings are molded hose or made out of plastic and are prone to cracking at junctions, causing coolant loss.
