Motor Oil Guide

Which oil is right for you? The current and previous API Service Categories are listed below. Vehicle owners should refer to their owner's manuals before consulting these charts. Oils may have more than one performance level. For automotive gasoline engines, the latest engine oil service category includes the performance properties of each earlier category. If an automotive owner's manual calls for an API SJ or SL oil, an API SM oil will provide full protection. For diesel engines, the latest category usually - but not always - includes the performance properties of an earlier category.
Gasoline Engines
Category	Status	Service
SM	Current	For all automotive engines presently in use. Introduced November 30, 2004. SM oils are designed to provide improved oxidation resistence, improved deposit protection, better wear protection, and better low-temperature performance over the life of the oil. Some SM oils may also meet the latest ILSAC specification and/or qualify as Energy Conserving.
SL	Current	For 2004 and older automotive engines.
SJ	Current	For 2001 and older automotive engines.
SH	Obsolete	For 1996 and older engines. Valid when preceded by current C categories.
SG	Obsolete	For 1993 and older engines.
SF	Obsolete	For 1988 and older engines.
SE	Obsolete	CAUTION - Not suitable for use in gasoline-powered automobile engines build after 1979.
SD	Obsolete	CAUTION - Not suitable for use in gasoline-powered automobile engines build after 1971. Use in more modern engines may cause unsatisfactory performance or equipment harm.
SC	Obsolete	CAUTION - Not suitable for use in gasoline-powered automobile engines build after 1967. Use in more modern engines may cause unsatisfactory performance or equipment harm.
SB	Obsolete	CAUTION - Not suitable for use in gasoline-powered automobile engines build after 1963. Use in more modern engines may cause unsatisfactory performance or equipment harm.
SA	Obsolete	CAUTION - Not suitable for use in gasoline-powered automobile engines build after 1930. Use in more modern engines may cause unsatisfactory performance or equipment harm.