Dayton Daily News

Halderman: This is a continuation of the topic of engine oil. This week features the second of five columns devoted to engine oil information.

API rating

The American Petroleum Institute (API), working with the engine manufacturers and oil companies, has established an engine oil performance classification. Oils are tested and rated in production automotive engines. The oil container is printed with the API classification of the oil. The API performance or service classification and the SAE grade marking are the only information available to help determine which oil is satisfactory for use in an engine.

Gasoline engine rating

In gasoline engine ratings, the letter S means service, but it can be remembered as being for use in spark ignition engines. The rating system is open-ended so that newer, improved ratings can be readily added as necessary (the letter I is skipped to avoid confusion with the number one).

SA — Straight mineral oil (no additives), not suitable for use in any engine

SB — Nondetergent oil with additives to control wear and oil oxidation

SC — Obsolete (1964)

SD — Obsolete (1968)

SE — Obsolete (1972)

SF — Obsolete (1980)

SG — Obsolete (1988)

SH — Obsolete (1993-1997)

SJ — Obsolete (1997-2001)

SL — 2001-2003

SM — 2004

NOTE: Older-model vehicles can use the newer, higher-rated engine oil classifications where older, now obsolete ratings were specified. Newly overhauled antique cars or engines also can use the newer, improved oils, as the appropriate SAE viscosity grade is used for the anticipated temperature range.

The new oils have all the protection of the older oils, plus additional protection.

ILSAC oil rating

The International Lubricant Standardization and Approval Committee (ILSAC) developed an oil rating that consolidates the SAE viscosity rating and the API quality rating. If an engine oil meets the standards, a “star burst” symbol is displayed on the front of the oil container. If the star burst is present, the vehicle owner and technician know that the oil is suitable for use in almost any gasoline engine. This makes selecting oil easy — simply look for the starburst on the front of the container. The original GF-1 (gasoline fueled) rating was updated to GF-2 in 1997, GF-3 in 2000 and GF-4 in 2004.

European oil ratings

The Association des Constructeurs European d’Automobiles (ACEA) represents most of the Western European automobile and heavy-duty truck market. The organization uses different engines for testing than those used by API and SAE, and the requirements necessary to meet the ACEA standards are different yet generally correspond with most API ratings. ACEA standards tend to specify a minimum viscosity rating and certain volatility requirements not specified by API.

The ACEA rating uses A1 through A5 for gasoline engine oil ratings and B1 through B5 for diesel engine oil ratings. Starting in 2004, the ACEA started using combined ratings such as A1/B1, A3/B3, A3/B4 and A5/B5. Mercedes specifies their own oil specifications labeled 229.1, 229.3 or 229.5. Oils meeting these standards must be used, and many oils do not meet these standards. Also note that Mercedes recommends only the use of approved synthetic engine oil in all 1998 and newer Mercedes vehicles.

Japanese oil ratings

The Japanese Automobile Standards Organization (JASO) also publishes oil standards. The JASO tests use small Japanese engines, and their ratings require more stringent valve train wear standards than other countries’ oil ratings.