6.6L Duramax Billet Coolant Block Off Plate 2001-2023 Duramax Billet Coolant Block Off Plate (Replaces GM P/N: 97941204) OE covers are prone to leakage as the gaskets dry out and factory cast covers corrode. Our billet coolant block off plate with an integral O-ring is an upgrade for your rear engine cover and will the stop the coolant leaks for good. .
