Specifically formulated for the heavy duty inboard marine market, including cruisers and towboats calling for a 15W-40. Premium base stocks and additive package ingredients places Sierra Heavy Duty at the leading edge of lubrication technology.
Meets API Service classification up to CK-4
Meets the performance specifications for API service classification SM
Suitable for fuels on any sulfur level
Not for use in gasoline engines equipped with catalytic converters
