While I seldom paid much attention in those days... all of the oil cans had a rating on them that guaranteed the oil inside was refined to a specific standard. I did not realize until recently, that the testing of motor oil formulas is voluntary and has been going on for a hundred years (in 2019). Here is how it works...
The American Petroleum Institute traces its beginning to World War I, when Congress and the domestic natural gas and oil industry worked together to help the war effort.
At the time, the industry included the companies created in 1911 after the court-imposed dissolution of Standard Oil and the "independents", companies that had been "independent" of Standard Oil. They had no experience working together, but they agreed to work with the government to ensure that vital petroleum supplies were rapidly and efficiently deployed to the armed forces.
The National Petroleum War Service Committee, which oversaw this effort, was initially formed under the U.S. Chamber of Commerce and subsequently as a quasi-governmental body.
After the war, momentum began to build to form a national association that could represent the entire industry in the postwar years. The industry’s efforts to supply fuel during World War I not only highlighted the importance of the industry to the country but also its obligation to the public, as the original charter demonstrates.
The American Petroleum Institute was established on March 20, 1919: to afford a means of cooperation with the government in all matters of national concern to foster foreign and domestic trade in American petroleum products to promote in general the interests of the petroleum industry in all its branches to promote the mutual improvement of its members and the study of the arts and sciences connected with the natural gas and oil industry. That is the official explanation.
For us, as the end-user, the API oil ratings are insurance that we are getting what we pay for. The ratings/standards have changed over the years as technology advanced in both the refining of oil and the metals that make up the engines. Here is what rating was popular when your antique vehicle was new...
SN Current Introduced in October 2010, designed to provide improved high-temperature deposit protection for pistons, more stringent sludge control, and seal compatibility. API SN with Resource Conserving matches ILSAC GF-5 by combining API SN performance with improved fuel economy, turbocharger protection, emission control system compatibility, and protection of engines operating on ethanol-containing fuels up to E85.
SM Current For 2010 and older automotive engines.
SL Current For 2004 and older automotive engines.
SJ Current For 2001 and older automotive engines.
SH Obsolete CAUTION: Not suitable for use in most gasoline-powered automotive engines built after 1996. May not provide adequate protection against the build-up of engine sludge, oxidation, or wear.
SG Obsolete CAUTION: Not suitable for use in most gasoline-powered automotive engines built after 1993. May not provide adequate protection against the build-up of engine sludge, oxidation, or wear.
SF Obsolete CAUTION: Not suitable for use in most gasoline-powered automotive engines built after 1988. May not provide adequate protection against the build-up of engine sludge.
SE Obsolete CAUTION: Not suitable for use in most gasoline-powered automotive engines built after 1979.
SD Obsolete CAUTION: Not suitable for use in most gasoline-powered automotive engines built after 1971. Use in more modern engines may cause unsatisfactory performance or equipment harm.
SC Obsolete CAUTION: Not suitable for use in most gasoline-powered automotive engines built after 1967. Use in more modern engines may cause unsatisfactory performance or equipment harm.
SB Obsolete CAUTION: Not suitable for use in most gasoline-powered automotive engines built after 1951. Use in more modern engines may cause unsatisfactory performance or equipment harm.
SA Obsolete CAUTION: Contains no additives. Not suitable for use in most gasoline-powered automotive engines built after 1930. Use in modern engines may cause unsatisfactory performance or equipment harm.
For us who own and drive antique vehicles one of the things that disappeared in the 1980s, was the zinc additive package from motor oils. The zinc additive package was an anti-wear additive package to protect the older engines built 1970's and prior from excessive wear in the areas like between the lifters and the camshaft, rod bearings, and main bearings, and other high-stress areas.
Besides the stress of metal on metal engines didn't seal as well as they due today so it was common to have engine coolant leak into the cylinders from a leaking head gasket, which in turn would contaminate and dilute the engine oil. The zinc additive package helped reduce the damage from that coolant contamination.
Modern engines seal much better, are built using roller lifters and the cam shafts, and have a hardened wear surface to prevent wear... so the zinc additive is not as critical in today's engines. The zinc was removed from engine oil originally because it was plugging up catalytic converters which in turn affected the emissions and the performance of the vehicle. Our antique vehicles still need that additive package to prevent internal engine wear.
Getting Certified...
API’s Engine Oil Licensing and Certification System (EOLCS) is a voluntary licensing and certification program that authorizes engine oil marketers that meet specified requirements to use the API Engine Oil Quality Marks. Launched in 1993, API’s Engine Oil Program is a cooperative effort between the oil and additive industries and vehicle and engine manufacturers Ford, General Motors, and Fiat Chrysler and those represented by the Japan Automobile Manufacturers Association and the Truck and Engine Manufacturers Association. The performance requirements and test methods are established by vehicle and engine manufacturers and technical societies and trade associations such as (ASTM), (SAE), and the American Chemistry Council (ACC).
The Engine Oil Program is backed by monitoring and enforcement program that ensures licensees adhere to program requirements. This includes running physical, chemical, and performance tests on licensed engine oils and verifying that the API-registered Marks are properly displayed on containers and convey accurate information to consumers.
About half of the program’s licensees are based in the United States, and the other half are spread around the globe.
Marketers of engine oil must obtain a license from API to use the API Engine Oil Quality Marks: the API Service Symbol "Donut" and Certification Mark "Starburst." The use of the API Marks is a marketer's warranty that its licensed oils comply with the requirements set forth in API 1509 and API's Application for Licensure. The use of the marks also identifies the oil marketer as the marketing organization responsible for the integrity of a brand name and the representation of the branded product in the marketplace.
The license application requires the applicant to certify that its oils meet Engine Oil Licensing and Certification System (EOLCS) requirements. There is an initial charge for an oil company to get their oil certified, followed up by an annual renewal fee. Here is what it cost as of 2019.
Fee Schedule (USD)
License application fee $4,500
License renewal fee $4,500
Additional renewal fee based on volume $0.007
At time of annual license renewal, licensee must report volume of API-licensed engine oil sold. API assesses $0.0070 per gallon fee on each gallon reported in excess of 1 million gallons. All API-licensed engine oil brands, whether sold in packages or in bulk, must be counted in the volume reported.
Note... that the application and renewal fees are per license, not per engine oil. For example, if an oil marketer submits an application for one oil, the application fee is $4,500. If the marketer submits an application for more than one oil, the application fee is still just $4,500.
And like everything else there are those who do not follow the rules and display the API logos on oil containers that have NOT been tested and certified. The API takes that violation very serious... and catches numerous violators each year. Here are a few of the most recent bad guys...
So now you know a little bit more about the engine oil you buy, and who checks up on the companies selling engine oil, to insure you are actually getting what you are paying for. That should make you sleep better at night knowing somebody is minding the store...especially in this day and age. Your welcome.
