Amsoil Article: What is Motor Oil? What are the Differences in Motor Oil|page 2

Page 2 What is a Motor Oil continued

API Class

The American Petroleum Institute (API) developed a classification system to identify oils formulated to meet the operating requirements of various engines. The API system has two general categories: S-series and C-series. The S-series service classification emphasizes oil properties critical to gasoline- or propane-fueled engines. If an oil passes a series of tests in specific engines (API Sequence tests), the oil can be sold bearing the applicable API service classification. The classifications progress alphabetically as the level of lubricant performance increases. Each classification replaces those before it. SL oil may be used in any engine, unless the engine manufacturer specifies a “non-detergent” oil. SA and SB are non-detergent oils and are not recommended for use unless specified. New cars from 1980 to 1989 require SF oils, while new cars from 1990 to 1993 require SG oils. New cars beginning with the 1994 model year require oils with an API SH performance rating. Beginning with 1997, new cars require an API SJ oil. The year 2001 brought the introduction of SL oils. SM category is the most recent classification. It was introduced Nov. 30, 2004. SM oils are designed to provide improved oxidation resistance, improved deposit protection, better wear protection and better low-temperature performance over the life of the oil. SJ, SL and SM are the current API classes. SJ, SL and SM oils are widely available and ensure the best engine protection available. C-series classifications pertain to diesel engines. They are: CA, CB, CC, CD, CD-II, CE, CF, CF-2, CF-4, CG-4, CH-4, CI-4, CI-4 Plus and CJ-4. All are obsolete except CF, CF-2, CH-4, CI-4, CI-4 Plus and CJ-4 performance rated oils. Not all C-series classifications supersede one another. The current classifications, CF and CF-2 are specified for different applications. CF for Indirect-Injected Diesel Engine Service. Service category CF denotes service typical of indirect injected diesel engines and other diesel engines that use a broad range of diesel fuels in off-road applications, including diesel fuel with greater than 0.5 percent sulfur by weight. CF oils may be used in place of CD oils. CF-2 for Two-Stroke Diesel Engine Service. This service category is typical of two-stroke engines requiring highly effective control over cylinder and ring-face scuffing and deposits. CF-2 oils may be used in engines for which CD-II oils are recommended. CI-4 Plus for Severe-Duty Diesel Engine Service. CI-4 Plus typically is required in high-speed four-stroke diesel engines used in heavy-duty on- and off-highway applications. CI-4 Plus oils are especially effective in engines designed to meet 2002 exhaust emission standards. CI-4 Plus oils may be used in place of CD, CE, CF, CF-4, CG-4, CH-4 and CI-4 oils. CJ-4 for 2007 and newer diesel Engines. CJ-4 was developed to address special concerns about emission control engines and their operation on ultra-low sulfer diesel fuel (ULSD). These classification systems aim to help motorists choose the right oil for their needs. The choice depends on the engine, the outdoor temperature and the type of driving the engine must withstand. Think of the “W” in a motor oil’s classification as meaning “Winter.”

AMSOIL provides top-quality filters for every application

How Motor Oil Becomes Contaminated

Motor oil becomes unfit for service after a period of use. Two main reasons for this are the accumulation of contaminants in the oil and chemical changes (additive depletion and oxidation) in the oil itself. These factors cause deterioration of the oil and prevent it from doing the job of lubricating and cooling engine parts.

Abrasives Road Dust and Dirt

Design limitations of air cleaners, some oil fill caps, and crankcase ventilation systems allow some dust and dirt to enter the engine. Leaks in the intake system also permit unfiltered air to enter the engine. However, proper maintenance of the engine and its accessories can minimize the amount of contaminants entering the lubrication system and extend engine life. Metal Particles Normal wear of parts in an engine produces very small metal particles that are picked up and circulated by the oil. Particles of road dust and dirt increase the rate of wear and generate larger metal particles, that in turn are quite abrasive. These, too, are circulated through the engine by the oil. While oil filters help keep these particles at a minimum, they can’t remove them entirely.

Combustion By-Products

Water Combustion produces water vapor, or steam. When engine temperatures Acids The combustion process produces acidic gases which, like water vapor, condense on cylinder walls at cold engine temperatures and also find their way into the crankcase oil. These combine with water to cause rust and corrosion. Soot and Carbon Incomplete combustion produces soot, carbon and other deposit-forming materials. An engine running too “rich,” or with too much fuel, increases the amount of contaminants. In gasoline engines, light-load and low-speed operations increase these combustion by-products more than high load, high-speed operations. Diesel engines produce more of these by-products with low speed, high-load operations. Dilution When an engine is started or running abnormally, some unburned fuel in liquid form is deposited on cylinder walls. That means raw fuel leaks past the rings into the crankcase, where it reduces the viscosity of the oil. Dilution lowers the film strength of the oil and increases oil consumption. Usually this is a minor problem when engine operation is at high speed or high-temperatures, but it can be a problem in vehicles consistently used for short-trip driving. While all of the processes by which a motor oil is contaminated are not fully defined, the use of high-quality motor oils such as AMSOIL synthetic motor oils allows motorists continued protection of their engines along with extended drain intervals, all while limiting the contaminants in the oil and prolonging engine life. AMSOIL provides top-quality filters for every application. are high, most of the water remains in vapor form and goes out through the exhaust. However, when engine temperatures are low, such as at start-up, warm-up and short-trip operation in low ambient temperatures, the water vapor condenses (turns into a liquid) on cylinder walls and is picked up in the crankcase oil. Here it leads to the formation of sludge, rust and corrosion.

Engine Filtration and Maintenance

Engine Wear Automotive experts agree dirt is the number-one cause of engine wear. Analysis by Federal-Mogul Corporation reports that 43.4 percent of all engine bearing distress is caused by dirt. Engine dirt particles are so small – mere dust specks – and an engine is a highly sophisticated piece of machinery, crafted from the most durable metal alloys. How, then, can these minute particles bring down such a high-tech giant? The answer lies in the fact that dirt particles are extremely abrasive. They consist of razor-like flakes of road dust and airborne grit drawn into the engine through the intake manifold, as well as manufacturing scarf and wear-metal particles generated inside the engine. These particles are carried by the oil into the precision clearances between bearings and other moving parts. Once they work in between these parts, they grind and gouge surfaces, altering clearances and generating more abrasive debris. This wear cycle continues, making precision components sloppy and fatigued until they fail altogether. Filtration is the key to preventing costly engine repairs caused by dirt. Filtration removes contaminants by trapping and holding them outside the system of oil circulation. In order for a filter to be truly effective, it must be able to capture contaminants of all types and sizes. AMSOIL has developed a complete line of sophisticated filtration products designed to offer the best protection available against virtually all harmful engine contaminants.

Air Filtration

Air Filtration An engine “breathes” air to mix with fuel for combustion – about 9,000 gallons of air for every gallon of gas. All that air contains more than 400 tons of suspended dirt in one cubic mile over a typical city, and the concentration is much higher in rural areas where travel frequently is over unpaved roads. The air filter is the first line of defense against the abrasive airborne grit that gets into an engine. In order to do the job right, the air filter must effectively filter the dangerous particles without obstructing the vital flow of air that sustains the engine. Conventional air filters quickly become obstructed with dirt, reducing vital engine air intake, leading to poor engine performance and low fuel efficiency. They require frequent replacement. AMSOIL Filters Last Longer When properly cleaned at 25,000- mile intervals, AMSOIL Ea Air Filters are guaranteed for 100,000 miles or four years, whichever comes first. The use of exclusive nanofiber synthetic media allows AMSOIL Ea Air Filters to provide unsurpassed filtration protection for 25,000 miles or one year between cleanings. AMSOIL Ea Air Filters are the most efficient filters available to the auto/light truck market. Ea Air Filters’ synthetic nanofiber media removes five times more dust than traditional cellulose filter media alone and 50 times more dust than wet gauze filter media. AMSOIL Ea Air Filters have a much higher capacity and lower restriction than competing filters.

Oil Filtration

Oil Filtration Full-flow oil filters install directly into the line of oil circulation. The “fullflow” of oil passes through the filter as the oil journeys between the oil pump and the engine. A full-flow filter must be able to remove and hold contaminants without illustration of how oil is pumped through an engine. obstructing oil flow to the engine. Engine Filtration and Maintenance 0 1 2 3 4 5 6 0 20 40 60 80 100 120 Particle Size (Microns) Efficiency (%) Media Efficiency Comparison Nanofibers Cellulose Wet Gauze Most filters on the market compromise the filtration of finer particles by using a thin layer of porous filter paper. These filters have almost no extended cleaning ability since they have a low capacity for storing dirt. These “surface-type” paper filters quickly become restricted as debris builds up on the paper surface. When this happens, the filter by-pass valve opens and allows unfiltered oil into the engine. AMSOIL Ea Oil Filters are made with premium-grade full-synthetic media. The strictly controlled processing of this media ensures accurate filter construction, and is what allows Ea Oil Filters to deliver higher capacity and efficiency along with better durability. AMSOIL Ea Oil Filters have significantly lower restriction than conventional cellulose media filters. Their small synthetic nanofibers trap smaller particles and hold more contaminants, resulting in lower restriction. During the engine warm-up period, an Ea Oil Filter allows the oil to flow through the filter at a colder temperature than a typical cellulose filter. The additional filtering time decreases engine wear dirt particles in your engine, the harm they can cause .

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.Everyday, Americans improperly discard over one million gallons of dirty motor oil.

AMSOIL INC. is doing its part to eliminate that pollution. In 1972, AMSOIL developed the first API-rated, long-life synthetic motor oil. In 1983, AMSOIL pioneered by-pass ultra-fine oil filtration. Shortly after, AMSOIL introduced the revolutionary Trigard System, making fill-for-life motor oil a reality. AMSOIL is the only oil company that protects our environment in this way.

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