EOLCS Categories & Classifications

In the Engine Oil Licensing & Certification System (EOLCS) Categories and Classifications section you can find detailed information on American Petroleum’s current, latest and obsolete oil specifications. The documents  section is a public publication registry of the EOLCS program updates and program guidelines.

Oil Categories

The current and previous API Service Categories are summarized in convenient charts. 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 SN oil will provide full protection. For diesel engines, the latest category usually - but not always - includes the performance properties of an earlier category.

API FA-4 and the FA-4 Donut identify certain XW-30 oils specifically formulated for use in select high-speed four-stroke cycle diesel engines designed to meet 2017 model year on-highway greenhouse gas (GHG) emission standards. API FA-4 oils are not interchangeable or backward compatible with API CK-4, CJ-4, CI-4 PLUS, CI-4, and CH-4 oils. Refer to engine manufacturer recommendations to determine if API FA-4 oils are suitable for use.

ILSAC Standard For Passenger Car Engine Oils

The current and previous ILSAC standards are listed here. 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 ILSAC standard includes the performance properties of each earlier category and can be used to service older engines where earlier category oils were recommended.