Motor oil classification API SL. Marking of motor oils. Specifications of oils S and C

API (American Petroleum Institute) Motor Oil Classification System by applications and operational properties. The specification divides all engine oils into two categories: S - oils for gasoline and C - for diesel engines. Each class is assigned the letter according to the alphabet since A: API SA, SB, SC, SD, SE, SF, SG, SH, SJ... Similarly, with the category S. What you need to remember when choosing an oil, taking into account the classification of API - the higher the class, the oil is more modern and suitable for your motor. For example, if the manual specifies sJ classthen your car is exactly the class SM. accepted later, but at the same time it is impossible to use oil appropriate Sh accepted earlier than your class SM..

Universal oils for gasoline and diesel engines have the designations of both categories, for example API SG / CD, SJ / CF.

Classes diesel oils Divideced additionally for two-stroke (CD-2, CF-2) and four-stroke diesel engines (CF-4, CG-4, CH-4).

API categories: SA, SB, SC, SD, SE, SF, SG, CA, CB, CC, CD, CE, CF - Today outdated, however, in some countries, oils of these categories are still available, the API SH category is "conditionally acting" and can only be used as an additional, for example API CG-4 / SH.

ASTM D 4485. "Standard Specification for the quality of the operational properties of motor oils" (Standart Performance of Engine Oils)

SAE J183 APR96 "The quality of the operational properties of motor oils and operational classifications of engines (with the exception of energy-saving oils)" (ENGINE OIL PERFORMANCE AND ENERGY CONSERVING).

Classification of motor oils API The American Petroleum Institute (American Petroleum Institute) was established in 1969. The classification of the API is called the classification of the quality of motor oils.

This classification shares motor oils on:
oils for gasoline engines;
oils for diesel engines;
Oils for two-stroke engines;
transmission oils;

For each of these species, quality classes are provided that describe a certain set of properties and quality of automotive oils of each class.

On the label, the information on the API engine oil engine oil is provided in this form: API SM., API CF., or API SM / CF.

If a motor oil It can be used in both types of engines, then such oil is assigned two classes for diesel and for gasoline engines. On the oil label, these classes are separated by a slash, for example, API SJ / CF-4. At the same time, the first is the class of oil, which corresponds to a more preferred (according to the manufacturer of the car) application. That is, in the above case, the main purpose of the car - for gasoline engines, but the manufacturer allows its use in diesel engines.

It should be noted that the lack of information on the engineering oil label of compliance with any of the API classes unambiguously means that this is an automatic or does not have an API certificate at all, or the quality class assigned to it is outdated.

What do the API code characters mean?
The alphanumeric code is the designation of the oil class.
At the same time, the first encoding letter means the type of oil:
"S" - for gasoline engines (Service / Spark Ignition)
"C" - for diesel engines (Commercial / Compression Ignition)
"T" - for two-stroke engines (TWO-STROKE)

Motor Oil Quality Classes API: Gasoline Engines

API SN.
The new SN class was created by the American Oil Institute (API) in conjunction with the American Professional ASTM Association (American Society for Testing Materials) and SAE (Society of Engineers of the Automotive Industry).

The differences between the SN API class from the previous SM specification are much more scaligible than the differences of the SM class from SL. The main difference between the SN API from previous API classifications in limiting phosphorus content for compatibility with modern system neutralization systems, as well as integrated energy saving. That is, the oils classified according to the API SN will approximately correspond to ASE C2, C3, C4, without an amendment to high-temperature viscosity.

For new category The API SN Committee on Lubricants proposed to follow the same development scheme as with earlier categories of API and ILSAC. This means that all operational characteristics of motor oils for API and ILSAC will be equivalent to, except that the proposed requirements of the API SN do not include tests for wear on the Sequence IIIG method on the generated oils. These fuel tests and testing tests according to the Sequence VID method are important landmarks for oils applying for compliance with the ILSAC GF-5 standard.
The main differences between the ILSAC GF-5 from the previous classification of GF4, in the ability to work with biofuels, improved protection against wear and corrosion, greater fuel economy, improved compatibility with sealing materials and improved protection against sludgeing.

The requirements of the API SN and ILSAC GF-5 are close enough and low-viscosity oils are likely to be classified together in these two classifications.

Oils, the corresponding SN APIs can be used to replace the SM API and earlier.

API SM.
engines Since 2004 release.

The SM API class describes motor oils for modern gasoline (multiclapped, turbocharged) engines. Compared to the class API SL, engine oils that meet the requirements of the API SM must have higher levels of oxidation and premature wear Engine parts. In addition, the standards are raised relative to the properties of the oil at low temperatures. Motor oils of this class can be certified by the ILSAC energy saving class.

Motor oils that meet the requirements of the API SM can be applied in cases where the car manufacturer recommends the class API SL or earlier.

API SL.
Motor oils for gasoline engines Since 2000 release.

In accordance with the requirements of car manufacturers, the API SL class machine is used in multi-chamber, turbocharged motors operating on fuel mixtures that meet modern enhanced ecology requirements, as well as energy saving.

Motor oils that comply with the requirements of the API SL can be used in cases where the automaker is recommended class API SJ or earlier.

API SK.
Due to the fact that one Korean manufacturer of engine oils uses the reduction of SK as its corporate name, to eliminate the possible confusion of the letter "K" is not used to designate the category of motor oils for gasoline engines.

API SJ.
Motor oils for gasoline engines Since 1996 release.

Automotive oils of this class are designed for use in gasoline engines of passenger and sports cars, minibuses and lungs. truckswhich are serviced in accordance with the requirements of car manufacturers. SJ provides for the same minimum standards as sh as well additional requirements to nagara formation and working at low temperatures. Oils fall under certification by Energy Saving category API SJ / EC.

Motor oils that meet the requirements of the API SJ can be used in cases where the car manufacturer is recommended class SH or earlier.

API SH.
Motor oils for gasoline engines Since 1993 release.

Motor oils of this class are designed for use in gasoline engines. passenger cars, minibuses and light trucks of 1996 and older, in accordance with the recommendations of their manufacturers. Motor oils of this class were tested in accordance with the requirements of the Association of Chemical Products (SM).

The class is characterized by higher requirements compared to the SG class, and has been developed as a substitute for the latter, to improve the anti-carbon, antioxidant, antisository properties of oils and increased protection against corrosion.

The API SH class corresponds to the category of ILSAC GF-1 in all respects, except for the mandatory energy saving and, depending on the degree of fuel economy, refers to the category of API SH / EC and API SH / ECII.

Motor oils of this class can be used in cases where the car manufacturer is recommended by the SG API class or earlier.

API SG.
Motor oils for gasoline engines from 1989 to 1993 release.

Designed for use in gasoline engines of passenger cars, minibuses and light trucks of 1993 models and older working on unleaded gasoline with oxygenates. The engine oils of this class have properties that provide improved protection against carpets, oxidation of the machine and motor wear, in comparison with previous classes, and also contain additives that protect against rust and corrosion of internal parts of the engine.

API SG engine oils comply with motor oils for diesel engines API CC and CD. Can be used where the classes of the API SF, SE, SF / CC or SE / CC are recommended.

API SF.
Motor oils for gasoline engines from 1980 to 1989 releases.

These engine oils were used in gasoline engines of 1980-1989 releases operating on eaten gasoline, subject to availability and instructions of the engine manufacturer.

Provide enhanced resistance to oxidation, rust and corrosion, improved protection from the wear of parts, in comparison basic characteristics API SE class car, as well as more reliable protection From Nagara and slag.

Motor oils of the API SF can be used as replacements of previous API SE, SD or SC.

API SE
Motor oils for gasoline engines from 1972 to 1980.

These engine oils were used in gasoline engines of models of release of 1972-1979, as well as in some models of 1971.

Additional protection in comparison with API SC and SD machines. Can be used as SC and SD replacements.

API SD.
Motor oils for gasoline engines from 1968 to 1971.

The automal of this class was used in gasoline engines of passenger cars and some freight release of 1968-70, as well as some models of 1971 and later.

Improved protection compared to API SC motor oils, also applied exclusively if there is an engine manufacturer's recommendation.

API SC.
Motor oils for gasoline engines from 1964 to 1967 releases.

Usually used in engines of passenger cars and some trucks of 1964-1967. Reduce high and low-temperature nagar, wear, and also protect against corrosion.

API SB.
Motor oils for low-power petrol engines.

Motor oils of the 30s of the 20th century, which provided enough easy protection against wear and oxidation, as well as anti-corrosion protection of bearings in motors that are operated in light load modes.

SB Motor Oils SB can only be used if they are specifically recommended by the engine manufacturer.

API SA.
Motor oils for gasoline and diesel engines.

Outdated class of oils for use in old motors operating in such conditions and modes in which the protection of parts is not needed.

API SA engine oils can only be applied if they are recommended by the engine manufacturer.

Motor Oil Quality Classes API: Diesel Engines

API CJ-4
Motor oils for diesel engines Since 2006 release.

Classification of the CJ-4 API licensed since October 2006.

The CJ-4 API class is designed for heavily loaded diesel engines, which meet the key requirements for NOx emission standards and solid particles for the manufacture of 2007 production and Recommended for engines equipped with particulate filters, as well as other systems for reducing the toxicity of exhaust gases.

The CJ-4 API standard carries significant changes in response to the needs of manufacturers of new engines that respond new environmental standardswhich are introduced since 2007. On the oil API. CJ-4 is imposed by limits for some indicators: asilism is less than 1.0%, sulfur 0.4%, phosphorus 0.12%.

The CJ-4 API classification exceeds the requirements of earlier categories of API CI-4 Plus, CI-4 and can be used as their replacement.

API CI-4 Plus

The additional operational class of the API CI-4 Plus motor oils for diesel engines was introduced in 2004.

Compared to API CI-4, the requirements for the specific content of soot, as well as evaporates and high-temperature oxidation are increased. When certified in this classification, motor oil must be tested in seventeen motor tests.

API CI-4
Motor oils for diesel engines Since 2002 release.

API CI-4 class introduced in 2002.

These engine oils are used in modern diesel engines with various species Injection and supervision, as well as in engines with the recirculation system of exhaust gases (EGR).

The CI-4 API class has been introduced due to the emergence of new, more stringent requirements for the ecology and toxicity of exhaust gases, which are presented to engines issued from October 1, 2002. Requirements for plantation, sediments, viscous indicators, limit the TBN value are tightened.

The engine oil, the corresponding API CI-4, should contain appropriate wash-dispersing additives and has, in comparison with the CH-4 API class, increased thermal oxidation resistance, as well as higher dispersing properties. In addition, such cars provide a significant reduction in motor oil foam due to a decrease in volatility and reducing evaporation at operating temperature up to 370 ° C, under the influence of gases. Requirements for cold rockers are tightened, the resource of gaps, tolerances and motor seals increased by improving the driving fluidity.

The CI-4 API classification replaces the oils API CD, CE, CF-4, CG 4 and CH-4.

API CH-4
Motor oils for diesel engines Since 1998 release.

Engine oils of this class are used in four-stroke diesel engines, which are operated in high-speed modes and comply with the requirements of the norms and standards for the toxicity of exhaust gases adopted in 1998.

The API CH-4 car corresponds to the sufficiently strict requirements of both American and European manufacturers of diesel engines. Class requirements are specifically designed for use in engines operating on high-quality fuel with a specific sulfur content of up to 0.5%. At the same time, in contrast to the class API CG-4, the resource of these engine oils is less sensitive to use diesel fuel With a sulfur content of more than 0.5%, which is especially relevant for South America, Asia, Africa.

Motor oils API CH-4 comply with increased requirements and should contain additives, more efficiently prevent valve wear and water treatment on internal surfaces.

The oils of the GH-4 API can be used as substitutes of motor oils API CD, CE, CF-4 and CG-4, in accordance with the recommendations of the engine manufacturer.

API CG-4
Motor oils for diesel engines Since 1995 release.

The CG-4 API class was presented in 1995.

Motor oils of this class are recommended for four-stroke diesel engines of buses, trucks and tractors of the main and non-maternal type, which are operated in the modes of increased loads, as well as high-speed modes.

Motor oil API CG-4 is suitable for engines that use high-quality fuels with a specific sulfur content of not more than 0.05%, as well as in motors for which special requirements for fuel quality are not put forward (the specific sulfur content can reach 0.5% ).

API CG-4 Class Machines must more effectively prevent wear of internal parts of the engine, formation of a car on internal surfaces and pistons, oxidation, foaming, soot formation (these properties are especially needed for modern engines main buses and tractor).

The CG-4 API class has been created in connection with the approval of new requirements and standards for the ecology and toxicity of exhaust gases (edition of 1994). The main disadvantage limiting the massive use of this class, for example, in Eastern Europe and Asia, this is the essential dependence of the resource of the car from the quality of the fuel used.

Motor oils API CG-4 can be used in engines for which the CD, CE and CF-4 class API classes are recommended.

API CF (CF-2, CF-4)
Motor oils for diesel engines with indirect injection.

The digit through a hyphen means a two-or four-stroke engine.

CF class API describes motor oils recommended for use in diesel engines with indirect injection, as well as other types of diesel engines that operate on fuel of various quality, including with an increased sulfur content (for example, more than 0.5% of the total mass) .

Motor oils certified by the API CF class contain additives that contribute to a more effective prevention of deposits on piston, wear and corrosion of copper (with copper content) of bearings, which is of great importance for these types of engines, and can be pumped in the usual way, as well as using turbocharger or compressor.

Motor oils API CF can be used where the quality class API CD is recommended.

API CF-2 (CF-II)
Motor oils for diesel engines Since 1994 release.

Class API CF-2 introduced in 1994.

Motor oils of this class are commonly used in two-stroke diesel engines that operate in high loading conditions. The CF-2 API oils must contain additives that provide the protection of increased efficiency from wear of the internal parts of the engine, such as cylinders and rings. In addition, these cars must prevent the accumulation of deposits on the inner surfaces of the motor, that is, the improved cleaning function is characterized for these oils.

Motor oil certified by the CF-2 API class has improved properties and can be used instead of earlier similar oils, with the manufacturer's recommendation.

CF-4 API
Motor oils for diesel engines Since 1990 release.

API CF-4 class introduced in 1990.

Engine oils of this class can be used in four-stroke diesel engines, the operating conditions of which are associated with high-speed modes.

API CF-4 API must contain appropriate additives that provide a decrease in car utaway, as well as to protect against Nagara in piston group. The main purpose of the motor oils of this class is to use in diesel engines of heavy-duty tractors and other cars that are used for long-distance travels in highways.

In addition, such engine oils are sometimes assigned a dual class API CF-4 / S. In this case, if you have the relevant recommendations of the engine manufacturer, these cars can also be used in gasoline engines.

The quality requirements of the CF-4 API oils exceed the possibilities of the previous CE API class, so the CF-4 motor oils can be used instead of the CE API Class Oils, with the appropriate recommendations of the engine manufacturer.

CE API
Motor oils for diesel engines Since 1983 release.

The CE API class machine was intended for use in some heavy duty turbocharged engines characterized by significantly increased working compression. The use of such oils was allowed for engines both with low and high rates of the shaft.

The engine oils of the CE API were recommended for low-and high-rustic diesel engines released, starting since 1983, which were operated in high-load modes. Subject to the availability of the relevant recommendations of the manufacturer of the engine, these cars could also be used in motors for which motor oils of class API CD were recommended.

API CD-II ( CD-2)
Motor oils for two-stroke diesel engines Since 1985 release.

API CD-II class introduced in 1985 for use in two-stroke diesel engines and is, in fact, the evolutionary development of the previous class API CD. The main purpose of using such cars was to use in heavy powerful diesel engines, which were installed mainly on agricultural equipment.

The engine oils of this class meet all working standards of the previous class API CD, in addition, the requirements are significantly increased relative to the high efficiency protection of the engine from Nagara and wear.

API CD +.
Motor oils for diesel engines Japanese production.

Oils have high resistance to oxidation and thickening under the influence of soot accumulation, as well as increased valve assembly protection.

API CD.
Motor oils for diesel engines Since 1955 release.

CD class API introduced in 1955 for normal use in some diesel engines, both atmospheric and turbocharged, with increased compression in cylinders, where it is extremely important effective protection from Nagara and wear. Engine oils of this class were usually used in agricultural machinery.

Motor oils API CDs could be used in cases where the engine manufacturer did not put forward additional requirements for fuel quality (including fuel with an increased sulfur content).

The API CDs were required, compared with previous classes, ensure increased protection against corrosion of bearings and high-temperature carpets in diesel engines. Often, motor oils of this class called "Caterpillar Series 3", due to the fact that they comply with the requirements of Superior Lubricants (Series 3) certification, developed by the tractor company Caterpillar.

API SS
Motor oils for diesel engines Since 1961 release.

The CC API class was introduced in 1961 for use in some engines, both atmospheric and turbocharged, which were characterized by increased compression. Engine oils of this class were recommended for engines that were operated in moderate and high load modes.

Compared to earlier classes, Motor oils API SS were to provide more high level protection against high-temperature nagar and corrosion of bearings in diesel engines, as well as from rusting, corrosion and low-temperature Nagar in gasoline engines.

API St.
Motor oils for diesel engines from 1949 to 1960.

Motor oils for diesel engines operating with an average load on sulfur fuel.

The class was approved in 1949 as an evolutionary development of the CA API, when using fuel with a high content of sulfur, without special quality requirements. The API API was also intended for use in supervisory motors, which were operated in lightweight and moderate modes. Often, this class was called "Motor oils" Appendix 1 ", thereby emphasizing the compliance with the MIL-L-2104A military prescription application 1.

API Sa.
Motor oils for diesel engines from 1940 to 1950 release.

Motor oils for low-loaded diesel engines.

The automotive of this class is designed for use in diesel engines working in light and moderate modes on a high-quality diesel fuel.

The class was widely used in the 40s and 50s of the last century and cannot be used in modern conditions, if this is not provided for by the requirements of the engine manufacturer.

Motor oils API CA must have properties that provide protection from nagar on piston rings, as well as corrosion of bearings in supervising motors, for which special requirements for fuel quality, which is used are not provided.

Motor Oil Quality Classes API: Two-Point Engines

API TD.
Oils for suspended two-stroke engines of motor boats.

API TC.
Oils for engines with high oil quality requirements, except engine boats, such as motorcycle engines, snowmobiles. It is possible to use the TC API in cases where the class API TA or TB is required.

API TB.
Oils for high-speed two-stroke engines with a volume of 50-200 cm3, working under large loads, for example, motor scooters, chainsaws, motorcycles.

API TA
Oils for two-stroke engines with a volume of up to 50 cm3 with air cooled, For example, mopeds, lawn mowers.

Quality Class Motor Oil API: Transmission Oils

API GL-6
Transmission oils for hypoid gears with increased displacement, operating under high speeds, large torque and shock loads.

API GL-5
Transmission oils for hypoid gears with level of operational properties MIL-L-2105 C / D. These oils are preferably used in transmissions with hypoid conical gears and conical wheels with circular teeth for the main transfer In cars, in cardan drives of motorcycles and stepped gearboxes of motorcycles.

Oils are used specifically for hypoid gears with high mixing axis. For the very heavy Conditions operation with shock and alternate load. Recommended for hypoid gears operating under high speeds at small torque and shock loads on the gear teeth.

API GL-4
Transmission oils with high additives with the level of operational properties MIL-L-2105. These oils are preferably applied in stepped gearboxes and steering mechanisms, in the main gears and hypoid transmissions with a small displacement in cars and gell-free vehicles For transportation of goods and passengers and for non-transport work.

Oils are used for hypoid gears operating under high speeds at small torque and under conditions of low velocities at large torque.

Be sure to have highly efficient anti-promotional additives.

API GL-3
Transmission oils with high additives with the level of operational properties MIL-L-2105. These oils are preferably used in the step of gearboxes and steering mechanisms, in the main gears and hypoid transmissions with a small displacement in cars and non-timing vehicles for the transport of goods, passengers and for non-transport.

Oils are used for spiral-conical gears operating in moderately harsh conditions, as well as for conventional transmissions with spiral-conical gears operating in moderately harsh conditions in speeds and loads.

They have the best anti-wear properties than the GL-2 API.

API GL-2
Transmission oils for worm gears operating under GL-1 conditions at low speeds and loads, but with higher requirements for antifriction properties.

API GL-1
Mineral oils without additives either oil with antioxidant and anti-inflated additives, but without contamaged components for use in gearboxes with low-speed gearboxes and slip speeds.

Oils are used in cylindrical, worm and spiral-conical gear transmissions, working at low speeds and loads.

API MT-1
Oils for high-loaded units.

Designed for non-crown mechanical boxes Transmission of powerful commercial vehicles (tractors and buses).

Equivalent to the oils of the GL-5 API, but have increased thermal stability.

PG-2 API
Oils for the transmission of leading bridges of powerful commercial vehicles (tractors and buses) and mobile technology.

Equivalent by oils API GL-5, but have increased thermal stability and improved compatibility with elastomers.

Oil quality - This is a complex of properties that is necessary for the operation of oil for its intended purpose. To facilitate the selection of the oil of the required quality for a particular type of engine and operating conditions, the API motor oil classification system was created.

This classification was created and improved in collaboration with API (American Petroleum Institute), ASTM (American Society for Testing and Materials) and SAE. It defines the limits of various parameters (in particular, the purity of the piston, wear piston rings etc.) with the help of various test engines.

On the API system installed 2 operational categories of appointment and quality

1. For gasoline engines, where SE, SF, SG, SH, SJ, SL, SM, SN classes are valid.
2. For diesel engines, where CC, CD, CE, CF, CG, CH, CI, CJ classes are valid.

Universal oils for gasoline and diesel engines are denoted by two symbols of the corresponding categories: the first character is the main one, and the second indicates the possibility of using this oil for the engine of another type. For example, API CG-4 / SH is an oil optimized for use in diesel engines, but it can be used in gasoline engines for which the API SH category oil is prescribed and below (SG, SF, SE, etc.).

Categories Oils for gasoline engines of passenger cars

Categories Oils for Diesel Engines Commercial Car

Class API SN. The API classification is enacted in October 2010. Today it is the most recent (because the toughest) requirements that are presented to manufacturers of motor oils for gasoline engines.

Why do I need an API SN classification? What's new in the class API SN for a conventional car owner? What is the difference between the SN API? Do not rush to understand.

Why the API SN Classification?

The main reason for the appearance of the class API SN is the need to improve motor oils at all. Engine manufacturers every day "roll up" motors are more and more. It goes without saying, oils for such engines can not be left unchanged. Hence the phenomenon of the world API SN. Motor oils certified as the corresponding API SN imply the possibility of applying in all gasoline engines of the modern generation (Do not forget about the tolerances of the manufacturer defined for your car).

Requirements API SN.

An important API classification API classification can be noted by the introduction of the following requirements.

• motor oils, licensed API SN, can be applied in engines using biofuel
• class API SN obliges motor oils to be energy saving
• API SN places additional requirements for ensuring engine wear resistance
• motor oils API SN must provide a "long and happy life" Emissions control systems and "environmentally friendly" exhaust 🙂

A distinctive feature of the API SN (compared to the API SM) is compatibility with engine sealing elements. More recently, the API classification is not particularly taken care of the preservation of the glands and gaskets. Now everything is different. The SN API implies control over the engine RTI.

Last interesting Facts About class API SN. On the bench, which is directly responsible for testing engine oils (the same stand through which all engine oils must pass, fighting for the "honorable title" - API Service), changed the test engine! Instead of the V-Forend Eight of 4.6 liters of 1993 (King of the pea of \u200b\u200brelease 🙂), a 3.6-liter V-shaped six-year-old six from General Motors was introduced. This is, of course, news! But the fact that the SN API can replace all previous API classes (API SM, API SL, etc. etc.) - perhaps, not news, but is a fact.

On this blog, you can learn about the motor oils of Conocophillips, corresponding and superior to the API SN requirements (will soon)

• Kendall. 5W30 GT-1 Full Synthetic Motor Oil WITH Liquid Titanium
• Kendall. Motor oil 10W30.
• Super Synthetic Blend Motor Oil 10W30
• 10w40 for athletes
• 10w40 semi-synthetic for cars with mileage

Lubricants began to be used long before our era. And if earlier the vegetable fats and fats of animal origin were used, since the 60s of the last century they were replaced by oil refining products. After that, the active development and improvement of motor oils began, and about 70 years ago, the first polymer viscosity modifiers appeared, due to which different classes and varieties appeared in engine oils soon, corresponding to the temperature regime of a certain time of the year, and all-season types of lubricants appeared.

From the moment the composition and technical quality of oils have undergone many changes, but their main purpose remains unchanged. The engine oil is designed to cover with thin, but with a strong, film moving parts, thereby protecting them from friction among themselves.

To date, there are several oil classification systems that allow us to divide lubricants for their operational qualities, specifications, as well as appointment. Among the main generally accepted systems of one of the most famous is the classification of motor oils by API. It was introduced in the late 50s of our century by the American Institute of Oil, and the fundamental principle in it is classification in two categories - S and C, that is, for gasoline and diesel engines, respectively.

Specifications of oils S and C

As noted above, the API system assumes division into two main categories, but there is a third designation of the quality of lubricants. Of these, each view is independent:

All these standards are denoted by the index of two letters, for example, Sn, SM, SH, SG, CF, CI, where the second value is an indicator by the level of operational characteristics. At the same time, the closer to the end of the Latin alphabet is the letter existing in the designation, the higher the oil level according to the API. For example, such a designation on the product as an API SL, SM or SN means superiority over the SF API.

Gasoline engines: quality classes, their designations and decoding

Specification Oils for diesel engines

Among the modern specifications of motor oils, oils of class CI and CF are most popular. It is they who are designed to meet all the features of modern diesel engines and meet all standards.

Video "API classifications"