There are some more interesting cycles such as the approximately 20-year cycle of planetary alignments which, as I understand it, is the basis of astrology. There is also a 20-year cycle in college football, at least according to some sports writers. I havent figured that one out as yet.

Some cycles are longer than others – a 20,000-year cycle of rainfall in the Middle East, and an approximate 200 to 250-year cycle of minimum sunspot activity. In fact, there is some evidence (albeit disputed) that we may be in the beginning stages of the next minimum in sunspot activity. The last one occurred around 1650 to 1715 and is referred to as the Maunder Minimum. During that time, the Northern hemisphere experienced some of the most severe winters in recorded history. Global warming advocates, beware!

At this point, Im sure you are asking yourself, what cycle is he talking about and how does it relate to engine oils? Actually, the cycle in question doesnt have a name but arose in a conversation I had with Bob Olree of General Motors at Decembers ASTM meeting in Phoenix. Olree pointed out that there is an approximately 20-year cycle in engine oil standard setting, since around 1948. Each cycle is characterized by a lot of activity, standard setting, testing, and ultimately inertia.

Additives had been introduced into engine oil formulations in the 1930s. Most notably, the first synthetic petroleum additives were pour point depressants. By 1932 a major advance in base stock refining (solvent extraction) resulted in oils which could operate at higher temperatures. However, the increased temperatures resulted in corrosion to recently introduced metal alloy bearings. To control this problem, oxidation inhibitors and corrosion inhibitors were added.

In 1941, detergents were incorporated into engine oil formulations to control deposit formation and to reduce valve sticking. Viscosity index improvers also made their appearance. In fact, by this time most of the additive components we now see in modern engine oil formulations were in use, except for ashless dispersants and friction modifiers.

1948-1968: The Formative Years

World War II was just over and postwar United States was booming. For the first time, consumer engine oils generally contained additives. During the war, the available additive technology was reserved for the war effort, but now all of the technical advances of the war years were being incorporated into consumer vehicles. The American Petroleum Institute introduced the first non-viscosity-related engine oil standard, which designated oils as Regular, Premium or Heavy Duty. However, no testing standards existed.

It soon became clear that some sort of standard needed to be set for engine oil performance. In 1952, API and ASTM developed the Engine Service Classification System. Revised in 1955 and 1960, it used the designations MM (motoring moderate), ML (motoring light) and MS (motoring severe) for gasoline engines.

This seemed fairly simple and easy to understand. However, there were no rigorous tests and limits set for these designations. The table above (from Lubricant Additives, by Smalheer and Smith, pub. 1967) describes the tests that were used to define these categories in 1965.

Youll note that only the MS (motoring severe) category had any significant testing, added in December 1965. Prior to that, there were tests defined by military specifications, but that was about it. In the 1960s, oil marketers obtained military approvals for their oils as the only way to define performance.

But that wasnt really reflective of what was going on with automobile manufacturers. They were in the beginnings of emissions controls, specifically the positive crankcase ventilator (PCV), which caused a lot of rusting to occur within the engine. The Ford Falcon Rust Test as well as the Sequence II or IIA were implemented to try to catch this problem. And it was apparent that some system was needed to grapple with the issues of oil specifications and minimum performance standards.

1968-1988: The Tripartite Years

In 1969 and 1970 the Tripartite was formed to implement better oil category setting. It included API to represent oil marketer interests, ASTM to represent the testing protocols required to demonstrate adequate performance, and SAE to bring in the OEMs. SAE Document J1146 defined the responsibilities of each along with a timetable for category development.

Interestingly enough, J1146 was only approved in 1976. Much of what happened before that was impromptu or developed on the fly. It was actually the outgrowth of the work done to develop SAE J183, which was first approved in 1970. SAE J183 determined that there were eight different service categories, and defined them by service description (from API) and engine oil description (from ASTM). API soon had a system designating engine oil service categories by letter: S categories indicated gasoline engine oils, and C categories would be for diesels. We all recognize this as the SA, SB, SC, etc. system. The constant throughout has been viscosity as documented in SAE J300.

Right from the beginning, API declared SA, which defined non-additive engine oil, to be technically obsolete. As new engine requirements and engine oil demands were identified, the letters advanced and earlier categories became technically obsolete. The list of obsolete passenger car oils now includes SA, SB, SC, SD, SE, SF and SG.

One shortcoming of this system, at least in the eyes of automotive OEMs, is that it did not include a way to define fuel economy – which the governments CAFE mandates had made a crucial issue. Using an energy-conserving engine oil to certify their vehicles would give OEMs a small but significant edge in meeting CAFE targets. However, the oil had to prove its mettle, be readily available to the consumer and be competitively priced.

To address this concern, API introduced the Service Symbol, commonly called the Donut, in 1982. The donut presents API category letters, SAE viscosity grade and any energy conserving properties within one, easily recognizable symbol. ASTM worked to develop a method of measuring fuel economy gains due to oil and, in 1984, SAE J1423 was introduced, defining Energy Conserving engine oils.

The OEMs were not yet completely satisfied, since there was still no single identifier to aid consumer awareness of which oil to use. Viscosity grade, performance category and now fuel economy still required separate attention, and could appear almost anywhere on the label. While APIs donut represented an improvement in communicating engine oil quality, the OEMs felt that it confused most consumers. They were adamant that an evergreen symbol was needed, one that would be right all of the time. APIs members were not excited by this as they felt that it genericized their brands.

1988-2008: The ILSAC Years

In 1988, the U.S. and Japanese automakers formed ILSAC, the International Lubricant Standardization and Approval Committee, and issued an elaborate proposal the next year called the North American Lubricant Standardization & Approval System. This proposal was quickly beaten back by the oil industry, but API and the American Automobile Manufacturers Association subsequently went on to develop APIs Engine Oil Licensing & Certification System (EOLCS).

As that progressed, other efforts were tightening quality for engine oils. The Chemical Manufacturers Association (now the American Chemistry Council) introduced the Products Approval Code of Practice in 1992, strictly defining how engine oils are to be tested and approved. Base oil interchange guidelines were introduced to categorize base oils and document how to switch between them without compromising performance in an already-licensed oil. And viscosity grade read-across guidelines were written, allowing data generated from engine testing of one viscosity grade to be reliably extrapolated to another viscosity grade.

At the same time, the auto industry created a new specification for passenger car engine oil, the GF (Gasoline Fueled) series. It was accompanied by a new starburst logo, unveiled in January 1993 and intended as a user-friendly symbol for oils that meet GFs energy-conserving specifications. Technically owned by API, the starburst joined the donut as licensing symbols for crankcase oils.

In July 1994 the first of the GF series, GF-1, was issued. Almost at once, ILSAC announced that it needed the next level, GF-2, as soon as possible. Progress on GF-2 was slow, however, and in mid-1995, frustrated automakers declared they would unilaterally issue the spec they wanted. Faced with this threat, API and ASTM promptly approved GF-2. The new oils had lower phosphorus levels, better fuel economy and less volatility than their predecessors.

With the ink barely dry on GF-2, the auto side made a formal request to SAE to evaluate the need for GF-3. Initially, they wanted GF-3 oils in the marketplace by 1998 or soon thereafter, and for the upgrade to deliver even more fuel economy, emissions system protection and extended drain intervals. They got the oil they wanted, but not the timing: GF-3 wasnt done until September 2000.

Nobody liked that. At last, the ILSAC/Oil Committee – a balanced group of auto companies (the ILSAC side) and engine oil and additive companies (the Oil side) – was created to determine need and manage the introduction of new engine oil categories. The first fruit of this new collaboration was GF-4, our current category introduced in 2004. ILSAC/Oil is now in the midst of developing GF-5 oils for introduction in 2010. (See page 26 for more details on how GF-5 is going.)

2008-2028: The What-next Years?

So what does the future hold for the cycle of engine oil category development?

Certainly, there will continue to be a need for engine oils to lubricate internal combustion engines. The latest information on automobile age says that the average age of vehicles on U.S. roads is very close to 10 years. Thats both a testament to the quality of the vehicles and the lubricants that are protecting them, and a statement about the cost of replacement. It also means that engine oils as we know them today will still be needed a long way down the road.

However, there is also the looming specter of alternative powerplants that will affect what kind, if any, engine oil might be required. Lets face it, electric motors and fuel cells dont need fully formulated engine oils. Their entry into the market place is probable, but when and to what degree is another question. So, for the time being, ILSAC/Oil will keep setting the standards.

There are cycles all right, and this one will continue for awhile.