Originally Posted By: Silver_civic
Hello everyone and I have maybe a real dumb question; you decide. When did the oil companies and people that govern them (the API I am thinking?) set up the rules, etc that say that 5w30 oil or 10w30 oil is safe and recommended for cars and trucks? Also how often do the API ratings and so forth change and what are some of the ground rules so to speak that all oils must meet, exceed or be capable of?
sorry if this is a dumb, new guy question; I am a little curios is all.
let me know your thoughts and opinions and facts as I know there are some really smart and educational folks on this board.
thank you all
adam
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The International Lubricant Standardization and Approval Committee (ILSAC) is responsible for the creation of passenger car engine oil specifications. The specification requirements are developed and introduced by ILSAC/OIL which is a separate entity from ILSAC. The ILSAC/OIL committee has two branches. ILSAC is representatives from the Alliance of Automobile Manufacturers (AAM) and the Japanese Automobile Manufacturers Association (JAMA) and OIL is representatives from oil industry organizations, the American Petroleum Institute (API), and the American Chemistry Council (ACC).
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http://www.gf-5.com/process_and_industry/industrycommittees/committeeactivities/
The U.S. & Japanese auto industry drives the specs for new oil formulations for the U.S. The oil people (API) and additive makers (ACC) are there to help agree on what is feasible and affordable in both the testing and the production of the oil. For example, even longer catalytic converter life was needed (EPA requirement???). Phosphorus, part of the cheap & effective antiwear agent ZDDP, poisons catcons. The auto makers did not want the phosphorus amount reduced from what it is now, so they agreed to make the oil less volatile to keep the phosphorus in the engine and out of the exhaust.
The API follows ILSAC with oil Service Categories...all ILSAC GF-4 engine oils are API SM, but not all SM oils meet the GF-4 spec, for example.
This link provides the tests the oil has to pass. Some of the tests involve running the oil in test engines for many hours, then doing lab tests on the used oil and/or on engine parts. Some of these tests are very expensive as well as time consuming, so all are a matter of negotiation. Not every oil is tested. Approved packages of addtives and approved base oil and substitution charts are used by the oil blenders.
Here is a spider diagram showing what is changed and not changed in GF-5 oil vs. GF-4
http://sas-origin.onstreammedia.com/orig...derDiagram.html
