Together with the SAE classification of the oil, which characterizes its viscosity, the API determines its applicability to a specific engine. You can read what the API itself is and what other classifications there are.
For most modern gasoline engines It is envisaged to use oil of the SL quality group if the engine was produced before 2004 or SM if after. In some places, if the year of manufacture is before 2001, SJ oil is allowed.
The reference books say the following:
“SJ - Oils for engines produced in 1996-2001. They contain fewer environmentally harmful impurities than SH oils and have energy-saving properties.
SL – Oils for engines produced since 2001. They have significantly improved detergent, antioxidant, anti-wear and energy-saving properties, reduced volatility and good compatibility with exhaust gas catalysts.
SM – Oils for engines produced since 2004. Oils in this category meet the increased requirements of manufacturers of new generation engines. Replace oils of SJ and SL groups.”
There is a new SN oil, but there is little information about it yet. It is clear that SN group oils can be considered the best today. And they are capable of replacing everything that was produced before. That is, if the car's instructions allow SJ oil, then SN is also suitable for it.
For comparison, the most common and popular groups SL and SM were selected
So, what would you like to have from perfect oil? Firstly, it must ideally and optimally lubricate the parts, and in all engine operating modes. This means reducing friction as much as possible, thereby increasing power and reducing fuel consumption. Secondly, minimize wear, thereby extending the life of the motor. Thirdly, to serve as long as possible, reducing the cost of replacing it. Fourthly, reduce environmental damage from the engine; in the civilized world this point is considered very important.
It’s good to have some harmony in the price-quality ratio.

OIL AGING

There are several reasons and factors for oil aging. Oil is a complex combination hydrocarbon compounds, with various additives and inclusions called an additive package. In the combustion chamber remaining after moving the piston to bottom dead point, the oil film takes on the full power of the heat flow, which gradually changes the structure and composition of the oil. After all, only a small part of this film burns out, and the rest, overheated, with volatilized light hydrocarbons, oxidized by contact with oxygen at high temperature, is washed into the engine sump. There is not much of this modified oil per cycle - the film thickness is micron, but there are a lot of cycles. There is no such heating in the bearings, maximum up to 180 degrees, but the pressures are very high, reaching 30...40 MPa. This also leads to a change in the properties of the oil. In addition, in the oil pan it comes into contact with crankcase gases, which are hot and aggressive.
Oil must wash the engine - it does wash it, but at the same time it is saturated with contaminants, both mechanical and organic. Some of them will sit in oil filter, but something will remain in the oil volume. And, in addition, at the same time, detergent components, an important part of the additive package, are activated.
For modern “synthetics”, the stated resources are large - 20...30 thousand kilometers.

Tests on an aged engine

The more oil is supplied to the cylinders, the faster it ages. Thicker oil films on the cylinder walls mean that more oil is exposed to heat during each cycle. And its volume in the crankcase is constantly decreasing - due to large waste. Increased blood pressure crankcase gases and their higher temperature also increases the rate of oil oxidation. And the sharply increasing amount of deposits in an old engine requires more - detergent additives.
Therefore, it is logical to speed up oil testing on an artificially aged engine. For testing, a special engine was assembled, with normal bearing clearances and sharply increased clearances in the cylinder-piston group.

SL, SM

Modern “synthetics”, identical according to SAE, 5W40, were selected for testing.
Now let's try to search different oils according to API classification. It would be correct if all oils were of the same brand, but of different API groups. But, alas, this does not happen - higher quality oil from all companies simply displaces its predecessor. Therefore, you will have to choose from what is available. But, to increase the reliability of the results, two oils were included in each comparison group.
The first sample is Esso Ultron oil (1,100 rubles per canister), which has a transitional quality class of SJ/SL. The second is BP Visco 5000 oil (1070 rubles per canister). From the SM family - French Motul X-Clean 8100 (2810 rubles per canister). As a pair, they took a completely new Dutch oil NGN Gold (1030 rubles per canister).
After each test cycle, the motors were disassembled, measured, and parts were weighed to determine wear and the degree of contamination.
After that, tests were carried out on a motor assembled taking into account all the requirements for clearances, practically new, unworn, and well-run in. Standard test cycles were run on it sequentially, first for all fresh oils, then for those “killed” by the resource cycle. And already here they measured power, fuel consumption, and environmental parameters.
The first cycle of tests - on fresh oils - did not reveal any particular difference in the engine response to the API group - everything remained within the measurement error.
And the second cycle, using used oils, put everything in its place. Synthetic oils the SL groups sharply decreased their performance compared to their fresh samples, while the Motul and NGN Gold decreased to a significantly lesser extent. The difference between oils of different categories was already much more noticeable - up to 6...7% in fuel consumption, up to 10% in toxicity, and 2...4% in power between the Esso-Visco and Motul-NGN groups. Moreover, the engine responded more than others to the aging of BP Visco oil.
The test results are summarized in the table:

This is how the operating high-temperature kinematic viscosity of oils changes various groups via API. First - a decrease, this is the destruction of thickening additives. And then - growth. This is a consequence of decomposition and changes in the properties of the base oil. The less pronounced this process is, the more resource oils

In terms of viscosity, all oils clearly correspond to the range prescribed SAE class 5W40. Viscosity indices are very high, characteristic of good “synthetics” (“viscosity index” is a parameter indirectly responsible for cold start engine).
Look at the content of the active elements. This is a direct characteristic of the additive package. What is striking here is that their concentrations in the original oils of both the SL and SM groups are very close. Indeed, the vast majority of manufacturers use almost the same additive packages - there are only a few manufacturers of them in the world. But the base of all oils is different, and the numbers differ.
Sulfur content. Sulfur compounds hit catalysts hard. It is always present in the oil - both from base oil and as part of extreme pressure and anti-wear additives. Motul oil X-Clean turned out to be the leader in oil cleanliness from sulfur, and NGN Gold was the “leader” at the other end. But there are no regulatory restrictions on this parameter, and experience suggests that for most oils it is higher than 0.5...0.6% sulfur content.
Base number. For all oils it is quite high - this is a sign of cleaning ability. But SM, Motul X-Clean, and NGN Gold oils are lower. The more stable base of SM oils requires fewer detergent additives to maintain the required engine cleanliness, and excess alkali in the oil is harmful - it increases corrosion activity and reduces the service life of additives.
Analysis of the data obtained on used oils confirmed that, indeed, oils of the SM group are more stable. And this means their service life is longer.
Let's return to the motor test data. Everything is confirmed by the results in “physical chemistry”. Indeed, Motul X-Clean and NGN Gold gave a greater energy-saving effect - the engine, albeit a little, became more economical, a little more powerful, and this effect persists and even grows with parallel operation. But the main thing is that these oils produced noticeably less deposits in the engine itself, in the oil pan, on the valve mechanism, and on the pistons (and this is the most important thing). And wear of parts is also less, and significantly. And this is again confirmed by “physical chemistry” - see the content of wear products.
IS IT WORTH PAYING THE EXTRA? So, the bottom line. Do I need to pay extra for modern oils SM? For those who have a direct reference to SM oils in their instructions, this question has a clear answer. The rest have a choice.
Of course, SL class oils are also high quality, but SM actually have certain “advantages”. This and best protection motor from wear, and a lower level of deposits in the motor, and a longer service life.
The specific figure after which mileage it is necessary to change oils of one and another class is a purely individual parameter that depends on both the brand of the engine and its technical condition, and the quality of the fuel used, and the driving style. But according to estimates - good oils SM groups will give SL oils a 30...40 percent head start in terms of service life.

Opening the engine and weighing the parts after testing each oil made it possible to evaluate their protective capabilities. SM group oils really reduce wear more effectively - this was confirmed by our experiment

Table 1 PHYSICAL AND CHEMICAL INDICATORS OF MOTOR OIL SAMPLES

№	Oil parameter	Group SL		SM Group
		NGN Gold 5W40	Motul X-Clean 5W40	Esso Ultron 5W40	BP Visco 5W40
	General physical and chemical parameters
1	Kinematic viscosity at 40° C, cSt	81,0/94,35	84,18/106,73	84,36/99,51	80,08/96,46
2	Kinematic viscosity at 100° C, cSt	14,06/15,56	13,06/16,99	14,65/15,84	13,77/14,36
3	Kinematic viscosity at 150° C, cSt	6,24/6,79	5,85/6,97	6,06/6,62	5,79/6,45
4	Viscosity index	180/176	156/174	196/182	170/154
5	Conditional crankshaft rotation temperature, T 5000, degrees C (calculated)	-24/-21	-19/-20	-26/-21	-23/-21
6	Base number, mg KOH/g	11,5/10,1	9,8/8,2	8,4/7,7	8,0/7,2
7	Total acid number, mg KOH/g	1,82/2,73	1,90/2,77	1,91/2,30	1,21/2,23
8	Flash point in an open crucible, degrees. WITH	236/238	223/225	227/228	232/234
	Content of active elements in the initial oil sample
9	Sulfur content,%	0,32	0,27	0,42	0,20
10	Mass fraction of phosphorus, % wt.	0,12	0,15	0,16	0,12
11	Mass fraction of calcium, % wt.	0,32	0,38	0,45	0,23
12	Mass fraction of zinc, % wt.	0,18	0,16	0,19	0,13
	Content of wear products at the end of the test cycle
13	Iron content, ppm	15,5	12,0	3,5	4,5
14	Aluminum content, ppm	214,2	184,3	48,9	55,6
15	Chromium content, ppm	7,2	9,8	4,5	5,2

The numerator contains the indicators determined in the initial oil samples after the first test cycle (after 6 operating hours), the denominator – in the final samples (after 120 operating hours)

AVERAGED ENGINE PERFORMANCE OBTAINED WHEN OPERATING WITH VARIOUS MOTOR OILS

API Team	Changes in engine performance when running on engine oil... (relative to parameters obtained with Esso Ultron oil)	Motor indicators		Content of toxic components
		Power,%	Fuel consumption, %	By CO,%	According to SN, %	For NOx, %
SL	BP Visco	0.30/ -1,49	1.17/ -4.05	-3.63/-2.19	--2.89/ -5,02	--1.11/-0.53
S.M.	NGN Gold	0.55/ 2.45	1.67/5.98	--3.63/ 5.56	--1.44/ 9.56	1.22/3.91
S.M.	Motul X-Clean	0.28/ 2.65	1.54/6.35	--1.43/ 6.35	0.31/ 10.60	--2.38/0.43

In the numerator, indicators defined for fresh oil, in the denominator – for the final oil samples (after 120 operating hours)
Deterioration in indicators is highlighted in red, improvement in green, and change within the measurement error in blue.

Mass of deposits on control weight elements at the end of the test cycle

Deposits on the side surface of the piston are the most dangerous! They can lead to ring sticking - and hence loss of compression and piston overheating. These are approximately the types of deposits produced by completely killed mineral oils.

And these are SL group oils...

And these are SM groups. The difference is noticeable

There are also deposits in the engine crankcase after SL group oils, their presence is inevitable

This is what the same crankcase looks like after using SM oil

On valve mechanisms the difference is not so noticeable, but it is also there.. This is after the SL group oil

This is after the SM group oil

The API classification of motor oils was developed in 1969. It is quite common throughout the world.

Products are labeled with it famous manufacturers, such as Castrol, Motul, Shell. The marking indicates the type of car engine into which oil can be filled. Its decoding is quite simple. According to the API classification of oils, all lubricants are divided into:

• S – motor oils for gasoline engines;
• C – consumables for diesel engines;
• EC - energy-saving motor oils. They are of high quality, low viscosity, fluidity, and can reduce fuel costs.

Lubricants suitable for any motor are marked with a pair of symbols. The 1st symbol is considered the main one, the 2nd indicates that the petroleum product can be poured into a different type of engine. Example: API SM/CF oils.

Categories of oils for gasoline internal combustion engines

The API classification includes the following classes of oil for gasoline internal combustion engines:

1. SN – approved 10/01/2010. Contains limited quantity phosphorus. Compatible with new systems that neutralize emissions, it is energy saving.
2. SM – approved 11/30/2004. API class SM is intended for gasoline engines produced today. Better than SL, it protects engine parts from oxidation and early wear. Almost doesn't change own characteristics in low temperature conditions.
3. SL. Optimal for cars manufactured in the twenty-first century. According to the approvals of car manufacturers, this lubricant used in multi-valve, turbocharged power units that operate on lean fuel. The oil is environmentally friendly and energy saving.
4. S.J. Suitable for gasoline engines manufactured after 1996. This type of oil is intended for use in cars, sports cars, minibuses, and small trucks. When using it, a little soot is formed, the lubricant retains its properties in winter.
5. SH. Optimal for gasoline engines made after 1994. It resists soot, oxidation, wear, and corrosion well. Can be poured into cars, minibuses, freight transport. The main thing is to comply with manufacturer's tolerances. They are indicated in the table contained in the operating manual.
6. S.G. Suitable for cars manufactured no earlier than 1989. The additives contained in the oil protect the power unit spare parts from corrosion and rust.
7. SF. An obsolete category in the API motor oil specification. Lubricant related to it can be poured into internal combustion engines made after 1980.
8. SE. Suitable for engines manufactured after 1972.
9. SD. Motor oil for use in gasoline engines manufactured after 1968 (obsolete category). The oil was used in gasoline internal combustion engines cars, freight transport.
10. S.C. Oil fluid for engines manufactured no earlier than 1964. Commonly used in passenger car engines, trucks mobiles produced in 1964-1967.
11. SB. Lubricant for gasoline engines with low power. It provided rather weak protection of motor bearings from wear, oxidation, and corrosion. Such motor oil cannot be poured into a modern car (unless the opposite is stated in the operating manual).
12. S.A. It differs from previous oils in that it can be used not only in gasoline, but also in diesel engines. A very outdated group of lubricants that are almost never used today. Earlier high-quality protection motor spare parts through additives was not particularly required, so SA API oils were quite popular.

Brief description of oils by API

Categories of oils for diesel engines

API diesel engine oil may fall into one of the following categories:

1. CJ-4. It was introduced on 10/01/2006. It was developed specifically for engines with high loads. The lubricant meets the basic requirements for the formation of soot and solid elements for power units manufactured in 2007. There are restrictions on certain characteristics: ash content must be less than one percent, sulfur concentration - less than four tenths of a percent, phosphorus - less than twenty hundredths of a percent. Oils belonging to this API quality class have all the advantages of lubricants from other categories. They are also excellent for modern power units and comply with established environmental standards.
2. CI-4 PLUS. The lubricant forms little soot, evaporates slightly, and practically does not oxidize at high temperatures. Any oil certified to this API specification class has undergone approximately 17 manufacturing tests.
3. CI-4. This class was introduced into the API specification fifteen years ago. Similar motor oils are used in today's diesel engines with different types injection and supercharging. They contain special dispersing and detergent additives. Consumables are resistant to thermal oxidation and have good dispersing properties. They also significantly reduce the amount of smoke during operation. Volatility is reduced, evaporation begins when the temperature reaches three hundred and seventy degrees Celsius. The oil is very fluid and passes well throughout the entire lubricating complex. very coldy. This reduces wear on the sealing elements of the power unit.
4. CH-4. The class was introduced on December 1, 1998. Lubricants are used in four-stroke diesel internal combustion engines operating in high speed. They meet all requirements for the content of toxic substances in exhaust. These requirements were adopted nineteen years ago. Oily liquids, belonging to this category, are recommended to be poured into the engine by automakers from Europe and the United States of America. Lubricants are intended for use in engines that run on very high-quality fuel containing no more than five tenths of a percent of sulfur. However, they can be cast at sulfur concentrations exceeding the specified limit. This is especially important for South American, Asian, and African countries. Consumables contain additives that well protect the valves from wear and prevent the appearance of carbon deposits on engine parts.
5. CG-4. This API oil class was introduced twenty-two years ago. Petroleum products classified in this category must be poured into four-stroke diesel engines (buses, trucks, tractors - vehicles operated under highly loaded conditions and at high speeds). The level of sulfur in fuel should not exceed five hundredths of a percent. You can also pour this oil into power units, for which there are no special requirements for fuel quality (sulfur concentration can reach up to five tenths of a percent). Lubricants that are certified according to this class do not allow wear of engine parts, the appearance of carbon deposits in piston system. The elements of the power unit oxidize less, and little foam and soot are formed (such characteristics are very significant for the engines of today's buses and tractors). The main disadvantage, which limits the mass use of such consumables, for example, in Eastern European and Asian countries, is that the oils significantly depend on the quality of the fuel being poured.
6. CF-2. API CF 2 oils are intended for use in two-stroke internal combustion engines on diesel engines operating in difficult conditions. The class was introduced twenty-three years ago. Such motor oils are usually poured into highly loaded engines.
7. CF-4. This includes lubricants designed for use in four-stroke diesel engines manufactured after 1990. Unless the car manufacturer specifies otherwise in the owner's manual, the oil can be used in gasoline-powered internal combustion engines.
8. CE. Motor oils for use in diesel engines produced no earlier than 1983. They were used in very powerful turbo engines, which are characterized by significantly increased operating pressure compared to others.
9. CD. The class was introduced in 1955. Such oils were often used in agriculture(tractors, combines).
10. CC. This class appeared in 1961. This includes petroleum products that can be poured into moderately loaded engines.
11. C.B. The class was adopted in 1949. It was an improved CA class.
12. CA. Lubricants were poured exclusively into lightly loaded diesel power units.

Transmission oil categories

With classification transmission oils It is necessary to familiarize yourself so that, when choosing a lubricant for the transmission, you can decipher the markings. By means of the markings on the canister, it is possible to understand what the performance of the product is, what additives and base oils it consists of.

1. GL-1. Designed for cone-spiral, worm and manual transmissions(without synchronizers) installed in trucks and special equipment.
2. GL-2. Optimal for worm gearboxes that operate in low-speed and light-load modes. Typically used in tractor technology.
3. GL-3. Suitable for helical-cone transmissions operating under average conditions. Designed to lubricate helical and other truck gearboxes. Do not pour into hypoid transmissions.
4. GL-4. Automotive oils for hypoid transmissions operating in high speed mode with low torque/low speed mode with high torque. Today, these lubricants are often used in synchronized gearboxes.
5. GL-5. Lubricants are suitable for hypoid gearboxes that operate under conditions of heavy load on gear teeth and high speeds. They are usually poured into transmissions with offset axles. For synchronized manual transmissions, you must use petroleum products approved by the car manufacturer.
6. GL-6. Motor oils are intended for filling into hypoid gearboxes with a large offset. Today they are not used due to their complete replacement by GL-5 oils.

Lubricants began to be used long before our era. And if earlier vegetable fats and fats of animal origin were used, then starting from the 60s of the last century they were replaced by petroleum products. After that it started active development and improvement of motor oils, and about 70 years ago the first polymer viscosity modifiers appeared, thanks to which different classes and varieties soon appeared in motor oils that meet temperature conditions certain times of the year, and all-season types of lubricants have also appeared.

From that moment on, the composition and technical qualities oils have undergone many changes, but their main purpose has remained unchanged. Motor oil is designed to cover moving parts with a thin but durable film, thereby protecting them from friction with each other.

Today, there are several oil classification systems that make it possible to divide lubricants according to their performance, technical characteristics, and purpose. Among the main generally accepted systems, one of the most famous is the API classification of motor oils. It was introduced in the late 50s of our century by the American Petroleum Institute, and the fundamental principle in it is the classification into two categories - S and C, that is, for gasoline and diesel engines respectively.

S and C oil specifications

As noted above, the API system is divided into two main categories, but there is also a third designation for the quality of lubricants.

Of these, each type is independent:

All these standards are designated by a two-letter index, for example, SN, SM, SH, SG, CF, CI, where the second value is an indicator of the level of performance characteristics. Moreover, the closer to the end of the Latin alphabet the letter in the designation is, the higher the API oil level. For example, a product designation such as API SL, SM or SN indicates superiority to API SF.

Gasoline engines: quality classes, their designations and interpretation	Group
Description	SN SN lubricants differ from the SM specifications that preceded this category in that they contain much less phosphorus, which gives them additional energy-saving properties and makes SN compatible with the latest systems aimed at neutralizing exhaust gases
S.M.	SM was first introduced in late 2004. This class is more common today than CN, because it is intended for modern gasoline engines, including multi-valve and turbocharged engines. Lubricants in this category were developed taking into account the improvement of engines, and therefore are designed to increase their environmental safety and be more wear-resistant. SM differs from the previous SL category in its greater oxidation resistance and excellent protective properties from the formation of sediment and deposits, which certainly affects the high quality of lubricants. Two years after the release of SM, a category of oils for diesel engines was developed with the designation CJ4. SM specification products are intended for and designed specifically for vehicles manufactured since 2004.
SL	The SL class was developed shortly before the release of SM and SN. It is designed for car engines produced since 2001, and absolutely meets all modern standards and requirements, including high environmental friendliness and energy saving. SL are intended for modern engines, including multi-valve, turbocharged and engines adapted to run on lean fuel mixtures. On lubricants The SL group can also operate the engines for which the SJ category products are intended. Thanks to properties such as reduced volatility, SLs are distinguished by their long-term retention of their properties, making the replacement interval motor oil increases noticeably. Today, this category is valid and widely used by modern car owners.
S.J.	This class is also valid today. It was approved in November 1995, although the product was certified only a year later. Therefore, SJ category oils are used for cars with gasoline engines starting in 1996. They are successfully used in passenger cars and sports cars, as well as in engines of minibuses and small trucks. SJ shows good specifications, including resistance to the formation of sediment and soot, as well as the ability to retain its properties at low temperatures. In terms of these properties, oils of the SJ category are very close to products of the SH class, and therefore are quite suitable for use in cases where the car manufacturer recommends the use of SH category oils for the car.
SH	This category was created in 1992 and is considered conditionally valid. Oils included in this group are used in car engines produced in 1996 and earlier. In terms of its qualities, this class is superior to oils of the SG category, because it was developed to replace it. Therefore, SH class oils are successfully used for cars in which SG is recommended.
S.G.	Class SG is intended for engines manufactured in 1193 and earlier. Oils in this category have excellent protection against soot and are resistant to oxidation and corrosion. SG oils meet all the requirements for motor oils intended for API CC diesel engines, which means SG can be used for cars in which the manufacturer recommends the use of categories SF and SF/CC, as well as SE and SE/CC.

Specification of oils for diesel engines

Among modern specifications The most popular motor oils are CI and CF class oils. They are designed taking into account all the features of modern diesel engines and meet all standards.

C.I.

Category CI -4 approved in 2002. They are designed for various diesel engines, CI specification products are highly resistant to oxidation and contain dispersant additives. CIs are quite environmentally friendly compared to previous classes of oils. It is worth noting that from the general CI category there is another class - CI -4 PLUS. The improved class CI -4Plus was developed taking into account stringent requirements for oil volatility, oxidation at elevated temperatures and soot formation.

CF

The CF specification was created for diesel engines with indirect injection. They are characterized by a high content of various additives that prevent deposits on the pistons, and also protect against wear and corrosion. internal parts with copper content, for example, bearings. Class CF may be designated CF-4 and CF-2, which means motor oils intended for use in four-stroke and two-stroke (respectively) diesel engines. At the same time, CF-4 are designed for engines operating in accelerated mode, and CF-2 are ideal for engines that are constantly subject to increased loads.

API Classifications Video

Oh yes - the age-old question “what kind of oil to use..”

In principle, the answer to this lies within the competence of the manufacturer of a particular motorcycle model. The fact is that the engine and exhaust system designed to work with a specific type of oil.
To ensure that the consumer does not rack his brains if he chooses the oil himself, each model has a list of parameters that prevent confusion: standard oil viscosity SAE(American Association of Automotive Engineers) for example 10w40 and its classification according to the system API(Engine Service Classification System), for example SG. Data can be found in the User Manual.
This information is almost enough to choose an oil.

AN650 from 2002 to 2005 - API: SF or SG, SAE10W-40
AN650 from 2006 to 2013 - API: SF or SG or SH or SJ, SAE10W-40
AN400 from 1998 to 2006 - API: SF or SG, SAE10W-40
AN400 from 2007 to present - API: SF or SG or SH or SJ, SAE10W-40
AN250 from 1998 to 2006 - API: SF or SG, SAE10W-40
AN250 from 2007 to present - API: SF or SG or SH or SJ, SAE10W-40

there, in the instructions for Suzuki operation does not recommend the use of energy-saving oils according to the API classification, some of them SH, SJ, SL and SM, which have the EC (Energy Conserving) mark.

Another factor influencing the choice of oils is the presence of additives for clutch operation in an oil bath. This is important for all years AN650. Those. Only motorcycle oil needs to be poured into these devices. In AN400 and AN250, it is permissible to fill even automobile oil that matches the viscosity and API classification.

API oil classes:

For gasoline engines - oil classes on the S scale
Oil group	Recommended application	Vehicle years	Qualitative indicators
S.M.	Introduced in November 2004. Technological development trends are aimed at increasing their environmental safety, increasing maintenance intervals while maintaining operational reliability. Naturally, this makes adjustments to the process of improving engines, affecting the quality of lubricants. Following these trends, in November 2004, the API classification introduced a class for motor oils for gasoline engines - SM, which, compared to SL, implies increased requirements for lubricants regarding oxidation resistance, protection against deposits, wear, etc. Since October 2006, the category for diesel oils class CJ-4.	since 2004	-
SL	(Current). API planned to develop Project PS-06 as the next API SK category, but one of the motor oil suppliers in Korea uses the abbreviation "SK" as part of its corporate name. To avoid possible confusion, the letter "K" will be omitted for the next category "S". - stability of energy-saving properties; - reduced volatility; - extended replacement intervals.	since 2001	-
S.J.	(Current). The category was approved on November 6, 1995, licenses began to be issued on October 15, 1996. Automotive oils of this category are intended for all currently used gasoline engines and completely replace oils of all previously existing categories in older engine models. Maximum level of performance properties. Possibility of certification according to the energy saving category API SJ/EC.	since 1996	-
SH	(Conditionally valid). Licensed category approved in 1992. Today, the category is conditionally valid and can only be certified as an additional category to API C categories (for example, API AF-4/SH). According to the requirements, it complies with the ILSAC GF-1 category, but without mandatory energy saving. Automotive oils in this category are intended for gasoline engines of 1996 and older models. When carrying out certification for energy saving, depending on the degree of fuel economy, API SH/EC and API SH/ECII categories were assigned.	since 1993	higher for models from 1995 onwards.
S.G.	Licensed category approved in 1988. The issuance of licenses ceased at the end of 1995. Automotive oils are intended for engines of 1993 and older models. Fuel - unleaded gasoline with oxygenates. Meets the requirements for automotive oils for diesel engines of API CC and API CD categories. They have higher thermal and antioxidant stability, improved anti-wear properties, and a reduced tendency to form deposits and sludge. API SG automobile oils replace oils of the API SF, SE, API SF/CC and API SE/CC categories.	1989-1993	higher for four-stroke engines
SF	Automotive oils in this category are intended for engines of 1988 and older models. Fuel - leaded gasoline. They have more effective antioxidant, anti-wear, anti-corrosion properties than previous categories and are less prone to the formation of high- and low-temperature deposits and slag. API SF automotive oils replace API SC, API SD and API SE oils in older engines.	1981-1988	higher for two-stroke engines
S.E.	Highly accelerated engines operating in harsh conditions.	1972-1980	higher
SD	Medium-boosted engines operating in difficult conditions.	1968-1971	average
S.C.	Engines operating under increased loads.	1964-1967	-
S.B.	Motors operating under moderate loads are used only at the request of the manufacturer.	-	-
S.A.	Engines operating in light conditions are used only at the request of the manufacturer.	-	-

Every car owner should be able to decipher the motor oil markings printed on the product packaging, because the key to long-lasting and stable operation The engine is the use of a high-quality engine that meets all the requirements of the manufacturer. Such serious requirements are imposed by them due to the fact that oils have to work in a wide temperature range and under high pressure.

From this article you will learn:

The engine oil marking contains all necessary information to make the right choice, you just need to be able to decipher it

In order to streamline and simplify the procedure for selecting oil for a specific type of engine according to the required characteristics and tasks assigned to it, a number of international standards have been developed. Global oil manufacturers use the following generally accepted classifications:

• ACEA;
• ILSAC;
• GOST

Each type of oil marking has its own history and market share, deciphering the meaning of which allows you to navigate in choosing the necessary lubricating fluid. We mainly use three types of classification - API and ACEA, and also, of course, GOST.

There are 2 main classes of motor oils, depending on the type of engine: gasoline or diesel, although there is also a universal oil. Directions for use are always indicated on the label. Any engine oil consists of a base composition (), which is its basis, and certain additives. The basis of the lubricating fluid is oil fractions that are obtained from oil refining or artificially. Therefore, according to their chemical composition they are divided into:

• mineral;
• semi-synthetic;
• synthetic.

On the canister, along with other markings, the chemical is always indicated. compound.

What may be on the label of a canister of oil:

1. Viscosity grade SAE.
2. Specifications API And ACEA.
3. Tolerances automakers.
4. Barcode.
5. Batch number and production date.
6. Pseudo-marking (is not a generally recognized standard marking, but is used as marketing ploy, for example fully synthetic, HC, with the addition of smart molecules, etc.).
7. Special categories of motor oils.

To help you buy exactly the one that will suit your car's engine best, we will decipher the most important markings motor oil.

Motor oil marking according to SAE

The most important characteristic that is indicated on the markings on the canister is the viscosity coefficient according to SAE classification is an international standard regulating positive and sub-zero temperatures(limit value).

In accordance with the SAE standard, oils are designated in the XW-Y format, where X and Y are certain numbers. First number- this is a symbol for the minimum temperature at which oil is normally pumped through the channels and the engine cranks without difficulty. The letter W stands for english word Winter - winter.

Second number conventionally means the minimum and maximum value of the high-temperature viscosity limit of the oil when heated to operating temperature(+100…+150°С). The higher the number, the thicker it is when heated, and vice versa.

Therefore, oils are necessarily divided into three types depending on the viscosity value:

• winter oils, they are more fluid and provide trouble-free engine starting in the cold season. In the notation SAE indicator such oil will have the letter “W” (for example, 0W, 5W, 10W, 15W, etc.). To understand the limit value, you need to subtract the number 35. In hot weather, such oil is not able to provide a lubricating film and maintain the required pressure in oil system due to the fact that at high temperatures its fluidity is excessive;
• summer oils are used when the average daily temperature is not lower than 0°C, since its kinematic viscosity is high enough so that in hot weather the fluidity does not exceed the required value for good lubrication of engine parts. At sub-zero temperatures, starting an engine with such a high viscosity is impossible. Designated summer stamps oils with a numerical value without letters (for example: 20, 30, 40, and so on; the higher the number, the higher the viscosity). The density of the composition is measured in centistokes at 100 degrees (for example, a value of 20 indicates a limiting density of 8-9 centistokes at an engine temperature of 100 ° C);
• all-season oils are the most popular because they are capable of operating at both sub-zero and positive temperatures, the limit value of which is indicated in the SAE indicator. This oil has a double designation (example: SAE 15W-40).

When choosing an oil viscosity (from those approved for use in your car’s engine), you need to be guided by the following rule: the higher the mileage/older the engine, the higher the high-temperature viscosity of the oil should be.

Viscosity characteristics are the very first and important element classification and labeling of motor oils, but not the only one - It’s not right to choose oil based solely on viscosity.. Always it is necessary to choose the right relation of properties oil and its operating conditions.

Each oil, in addition to viscosity, has a different set of operational properties (detergent, antioxidant properties, anti-wear, tendency to form various deposits, corrosiveness, and others). They allow us to determine the possible scope of their application.

In the API classification, the main indicators are: engine type, engine operating mode, oil performance properties, conditions of use and year of manufacture. The standard provides for the division of oils into two categories:

• Category “S” – shows those intended for gasoline engines;
• Category “C” – indicates its intended use for diesel vehicles.

How to decipher API markings?

As we have already found out, API designation may begin with the letter S or C, which will indicate the type of engine into which it can be filled, and another letter designating the oil class, indicating the level of performance properties.

According to this classification, the decoding of motor oil markings is carried out as follows:

• abbreviation EC, which is located immediately after the API, indicate energy-saving oils;
• Roman numerals after this abbreviation talk about the level of fuel economy;
• letter S(Service) denotes applications oils for gasoline engines;
• letter C(Commercial) are designated ;
• after one of these letters comes performance level, indicated by letters starting from A(most low level) to N and further (the higher alphabet order the second letter in the designation, the higher the oil class);
• universal oil has letters from both categories through an oblique line (for example: API SL/CF);
• API markings for diesel engines are divided into two-stroke (number 2 at the end) and 4-stroke (number 4).

Those motor oils, which have passed the API/SAE test and meet the requirements of current quality categories, are indicated on labels with a round graphic symbol. At the top there is an inscription - “API” (API Service), in the middle there is a viscosity grade according to SAE, as well as a possible degree of energy saving.

When using oil according to “its own” specification, wear and the risk of engine breakdown are reduced, oil waste and fuel consumption are reduced, noise is reduced, and driving performance engine (especially when low temperatures), and also increases the service life of the catalyst and exhaust cleaning system.

Classifications ACEA, GOST, ILSAC and how to decipher the designation

The ACEA classification was developed by the Association European Automobile Manufacturers. It indicates the performance properties, purposes and category of motor oil. ACEA classes are also divided into diesel and gasoline.

The latest edition of the standard provides for the division of oils into 3 categories and 12 classes:

• A/B – gasoline and diesel engines cars, vans, minibuses (A1/B1-12, A3/B3-12, A3/B4-12, A5/B5-12);
• C – gasoline and diesel engines with catalyst exhaust gases (C1-12, C2-12, C3-12, C4-12);
• E – truck diesel engines(E4-12, E6-12, E7-12, E9-12).

In addition to the class of motor oil, the ACEA designation indicates the year of its introduction, as well as the publication number (when updates were made) technical requirements). Domestic oils are also certified according to GOST.

Classification of motor oils according to GOST

According to GOST 17479.1-85, motor oils are divided into:

• kinematic viscosity classes;
• performance groups.

According to kinematic viscosity Oils are divided into the following classes:

• summer – 6, 8, 10, 12, 14, 16, 20, 24;
• winter - 3, 4, 5, 6;
• all-season – 3/8, 4/6, 4/8, 4/10, 5/10, 5/12, 5/14, 6/10, 6/14, 6/16 (the first digit indicates winter class, the second for summer).

In all of the listed classes, the higher the numerical value, the greater the viscosity.

By area of ​​application All motor oils are divided into 6 groups - designated from the letters “A” to “E”.

The index “1” denotes oils intended for gasoline engines, the index “2” for diesel engines, and oils without an index indicate its versatility.

Classification of motor oils according to ILSAC

ILSAC is a joint invention of Japan and America, the International Committee for Standardization and Approbation of Motor Oils has issued five motor oil standards: ILSAC GF-1, ILSAC GF-2, ILSAC GF-3, ILSAC GF-4 and ILSAC GF-5. They are completely similar to API classes, the only difference is that oils corresponding to ILSAC classifications are energy-saving and all-season. This classification is best suited for Japanese cars.

Correspondence ILSAC categories regarding API:

• GF-1(outdated) - oil quality requirements similar to API SH category; by viscosity SAE 0W-XX, 5W-XX, 10W-XX, where XX-30, 40, 50.60.
• GF-2- meets the requirement according to oil quality API SJ, and in terms of viscosity SAE 0W-20, 5W-20.
• GF-3- is analogous to the API SL category and has been in effect since 2001.
• ILSAC GF-4 and GF-5- respectively analogs of SM and SN.

In addition, within the framework of the standard ISLAC for Japanese cars with turbocharged diesel engines , used separately JASO DX-1 class. This marking automobile oils provides engines of modern cars with high environmental parameters and built-in turbines.

IN API classifications and ACEA formulate minimum basic requirements that are agreed upon between oil and additive manufacturers and vehicle manufacturers. Since engine designs different brands differ from each other, the operating conditions of the oil in them are not quite the same. Some major engine manufacturers have developed their own classification system motor oils, so-called tolerances, which complements the ACEA classification system, with its own test engines and field testing. Engine manufacturers such as VW, Mercedes-Benz, Ford, Renault, BMW, GM, Porsche and Fiat primarily use their own approvals when choosing engine oil. The vehicle's operating instructions must contain specifications, and their numbers are printed on the oil packaging, next to the designation of its class of performance properties.

Let's consider and decipher the most popular and frequently used tolerances present in the designations on cans of motor oils.

VAG approvals for passenger cars

VW 500.00- energy-saving motor oil (SAE 5W-30, 10W-30, 5W-40, 10W-40, etc.), VW 501.01- all-season, intended for use in conventional gasoline engines manufactured before 2000, and VW 502.00 - for turbocharged ones.

Tolerance VW 503.00 stipulates that this oil is for gasoline engines with SAE viscosity 0W-30 and with an extended replacement interval (up to 30 thousand km), and if exhaust system with a three-component neutralizer, then oil with VW 504.00 approval is poured into the engine of such a car.

For Volkswagen, Audi and Skoda cars with diesel engines, a group of oils with approvals is provided VW 505.00 for TDI engines, produced before 2000; VW 505.01 Recommended for PDE engines with unit injector.

Energy-saving motor oil with viscosity class 0W-30 with approval VW 506.00 has an extended replacement interval (for V6 TDI engines up to 30 thousand km, 4-cylinder TDI engines up to 50 thousand). Recommended for use for new generation diesel engines (after 2002). For turbocharged engines and PD-TDI pump injectors, it is recommended to fill in oil with the approval VW 506.01 having the same extended replacement interval.

Approvals for Mercedes passenger cars

The Mercedes-Benz automaker also has its own approvals. For example, motor oil with the designation MB 229.1 Intended for Mercedes diesel and gasoline engines produced since 1997. Tolerance MB 229.31 introduced later and corresponds SAE specifications 0W-, SAE 5W- with additional requirements that limit sulfur and phosphorus content. MB 229.5- This energy saving oil with extended service life for both diesel and gasoline engines.

BMW engine oil tolerances

BMW Longlife-98 This approval is granted to motor oils intended for filling into the engines of cars manufactured since 1998. An extended service replacement interval is provided. Meets the basic requirements of ACEA A3/B3. For engines manufactured at the end of 2001, it is recommended to use oil with approval BMW Longlife-01. Specification BMW Longlife-01 FE provides for the use of motor oil when operating in difficult conditions. BMW Longlife-04 approved for use in modern engines BMW.

Engine oil tolerances for Renault

Tolerance Renault RN0700 was introduced in 2007 and meets the basic requirements: ACEA A3/B4 or ACEA A5/B5. Renault RN0710 meets the requirements of ACEA A3/B4, and Renault RN 0720 according to ACEA C3 plus additional Renaults. Approval RN0720 designed for use in diesel engines latest generation with particulate filters.

Approval for Ford vehicles

Motor SAE oil 5W-30, approved Ford WSS-M2C913-A, intended for primary and service replacement. This oil Meets ILSAC GF-2, ACEA A1-98 and B1-98 classifications and additional Ford requirements.

Approved oil Ford M2C913-B Intended for initial filling or service replacement in gasoline and diesel engines. Also meets all ILSAC GF-2 and GF-3, ACEA A1-98 and B1-98 requirements.

Tolerance Ford WSS-M2C913-D was introduced in 2012, oils with this approval are recommended for all diesel engines Ford engines with the exception of Ford models Ka TDCi manufactured before 2009 and engines manufactured between 2000 and 2006. Provides the possibility of an extended replacement interval and refueling with bio-diesel or high-sulfur fuel.

Approved oil Ford WSS-M2C934-A provides for an increase in replacement interval and is intended for filling into cars with a diesel engine and particulate filter(DPF).Oil meeting specification Ford WSS-M2C948-B, based on ACEA C2 class (for gasoline and diesel engines with catalyst). This approval requires an oil with a viscosity of 5W-20 and reduced soot formation.

When choosing an oil, you need to remember a few basic points: right choice necessary chemical composition(mineral, synthetic, semi-synthetic), viscosity classification parameter, and know the necessary requirements regarding the set of additives (defined in the API and ACEA classifications). The label should also contain information about which brands of cars it is suitable for. this product. It is equally important to pay attention to additional engine oil symbols. For example, marking Long Life indicates that the oil is suitable for machines with extended service replacement intervals. Also, among the features of some compositions, one can highlight compatibility with engines with turbocharging, intercooler, cooling of recirculation gases, control of timing phases and valve lift height.