In everyday language, engine oil is understood to mean any type of lubricating oil that is suitable for lubricating an internal combustion engine .
In a broader sense, the two-stroke engine oils also belong to the category of engine oils, as do all lubricating oils that are intended for other engine types. However, these usually have other generic names geared to their specific purpose.
- Mineral oil : Mineral oil-based motor oil is made from base oils obtained directly from petroleum distillates .
- Partly synthetic oil : Partly synthetic motor oil is made from a mixture of mineral oils and synthetic base oils.
- Synthetic oil : Synthetic motor oil is made exclusively from base oils that have been obtained synthetically or not directly from petroleum distillates.
The SAE viscosity are classes since 1911 by the Automotive Society of Engineers determined.
Motor oils for motor vehicles are divided into summer and winter oils. This is to be understood historically, since motor oils used to be changed depending on the season. Multigrade oils that combine the properties of summer and winter oils are common today. Technical progress makes it possible to cover all seasons with the same engine oil. For special cases, such as racing or polar expeditions, single-grade oils are still available.
- According to SAE J300 (as of January 2015), summer oils are given one of the viscosity classes 8 (very thin), 12, 16, 20, 30, 40, 50 or 60 (very thick). The main distinguishing feature is the flow behavior at high oil temperatures. The load-bearing capacity of the lubricating film is better with a higher viscosity than with a lower one, but the viscosity itself is not a quality feature. The reference temperature for hot engine oil is 100 ° C, although even higher oil temperatures (up to a maximum of around 120 ° C, sometimes up to 130 ° C) can occur in the engine.
|Engine oil||Viscosity at 100 ° C|
|SAE 16||5.6 mm² / s to 6.9 mm² / s|
|SAE 20||6.9 mm² / s to 9.3 mm² / s|
|SAE 30||9.3 mm² / s to 12.5 mm² / s|
|SAE 40||12.5 mm² / s to 16.3 mm² / s|
|SAE 50||16.3 mm² / s to 21.9 mm² / s|
|SAE 60||21.9 mm² / s and more|
- According to SAE J300, winter oils are given one of the viscosity classes 0W (very thin), 5W, 10W, 15W, 20W or 25W, with the “W” standing for “winter suitability”. The low-temperature pump viscosity at a certain temperature is encoded as a numerical value according to the following scheme:
|Engine oil||Lowest temperature at which the oil can still be pumped under specified conditions (SAE J 300).|
|SAE 0W||−40 ° C|
|SAE 5W||−35 ° C|
|SAE 10W||−30 ° C|
|SAE 15W||−25 ° C|
|SAE 20W||−20 ° C|
|SAE 25W||−15 ° C|
- Multigrade oils can bridge the viscosity classes of two or more single-grade oils. In contrast to single-grade oils, they are therefore suitable for combined summer and winter operation.
When naming multigrade oils, the low-temperature viscosity with the addition W is always mentioned first, followed by the high-temperature viscosity after the hyphen.
These oils must meet the requirements of SAE J300 for both viscosity classes. Examples:
|Multigrade oil||Low temperature viscosity||High temperature viscosity|
|SAE 0W-40||SAE 0W||SAE 40|
|SAE 5W-40||SAE 5W||SAE 40|
|SAE 10W-40||SAE 10W||SAE 40|
|SAE 10W-60||SAE 10W||SAE 60|
|SAE 20W-60||SAE 20W||SAE 60|
|SAE 15W-40||SAE 15W||SAE 40|
|SAE 20W-50||SAE 20W||SAE 50|
In order to be able to bridge several viscosity ranges, multigrade oils contain polymers as viscosity index improvers.
The choice of viscosity class is generally based on the specifications of the vehicle manufacturer, or more specifically: the engine manufacturer. Normally, the designer of a machine knows best which structural features he has equipped the unit with and which viscosity class is necessary for the correct oil pressure.
Because that is the main reason for specifying the viscosity class: to ensure the correct oil pressure in the engine. Too high an oil pressure can "overpress" the motor seals, while too low an oil pressure cannot guarantee the lubrication of the bearings used in the motor.
Gear oils for motor vehicles have the viscosity classes SAE 70 (very thin) to SAE 250 (very thick).
Engine oils for aircraft with piston engines are in turn designated according to SAE J-1966 and J-1899 with the viscosity grades 65 to 120 according to their SUS value ( Saybolt Universal Seconds ).
The viscosity according to the SAE classification can not be seen absolutely. These are by no means measured values, but merely comparative values, the significance of which is limited to a firmly defined group. The viscosity data of different types of oil can not be compared with each other, but only within their group.
The following oils are roughly comparable in terms of their viscosity :
|Engine oil||Gear oil||Aircraft engine oil|
|SAE 20||SAE 80|
|SAE 30||SUS weight 65|
|SAE 40||SAE 90||SUS weight 80|
|SAE 50||SAE 90||SUS weight 100|
|SAE 60||SUS weight 120|
The above table (based on the viscosity at 40 ° C and a VI of approx. 100) is only intended to illustrate comparable flow properties. Aviation engine oils, for example, are not used in motor vehicles - and vice versa, since the two oils have completely different additives .
Single grade oils
The single-grade oil was the dominant market until the 1970s . Every oil offered had its assigned viscosity and was also designated with this. Motor vehicle engines were operated with oils of the viscosity grades SAE 20, SAE 30, SAE 40 or SAE 50. For special applications or extreme degrees of cold, the thin-bodied SAE 10 could still be considered, in racing or for use in extremely hot areas, single-grade oils of the almost honey-like viscous viscosity class SAE 60 could be obtained. Single-grade oils, with their guaranteed minimum viscosity, are still used today, especially for engines of older series, some of which are designed with large tolerances and running clearances.
The vast majority of engine oils commonly used today are so-called multigrade oils . These are based on low-viscosity base oils and are provided with special additives (e.g. polymers such as polyester or polyisobutylene ) so that their viscosity increases at higher temperatures. This enables the engine to be lubricated quickly during a cold start, less load on the starter at low temperatures and a sufficiently high level of lubrication reliability at higher outside and engine temperatures. This means that the same oil can be used in both summer and winter operation, which was not possible with the single-grade oils that were common in the past. The additives used are also called VI improvers, so they improve the viscosity index (VI) and thus reduce the temperature dependence of the viscosity.
The greatest weakness of multigrade oils, however, lies precisely in their strength: multigrade oils increasingly lose viscosity during operation - and the faster the higher the proportion of polymers in them. In plain language, this means: the larger the bridged viscosity range, the stronger and faster the oil "ages". The viscosity practically falls back to the level of the starting product, which is usually a rather thin oil. Because of this property, many racing mechanics, engine tuners and, above all, aviation enthusiasts swear by the classic single-grade oil to this day.
On the other hand, since the invention of synthetic oils, the oil manufacturers have got the problem of the rapid aging of their multigrade oils under control. Modern fuel-saving low-viscosity oils with very long change intervals (in some places the "life-long oil filling" is already tested ex works) would be inconceivable without the multi-range technology.
Oils with reduced high temperature viscosity
Today's engine designers are working with all the tricks to reduce fuel consumption even further. One of these tricks also has to do with the viscosity of the engine oil. If you reduce the viscosity of the engine oil in the high temperature range, the friction loss in the engine decreases at the same time. Less fuel is converted into heat, the output increases or the fuel consumption decreases with the same required output. This so-called H IgH T emperature- H IgH S hear viscosity (HTHS) of the engine oil is measured at a high oil temperature and high engine speed. The high speed ensures a high shear rate (shear gradient). However, these effects can only be achieved if the entire engine design is designed accordingly. In the case of older, unsuitable engine constructions, such oils with reduced HTHS viscosity can even lead to engine damage in extreme cases. They are therefore only used in vehicles whose manufacturers have given appropriate approval.
In essence, the HTHS indicates the stability of the lubricating film of an engine oil at an elevated temperature. If the value is above 3.5 mPa × s, the oil is very stable even at high temperatures. Values below this (below 3.5 mPa × s) are referred to as reduced HTHS viscosity, which also means less shear stability.
However, there is a trade-off between the ingredients in oils with high shear stability and the resulting combustion residues.
Example based on car diesel engines with particle filters (ACEA specification = C):
- C1: Low-SAPS oil with reduced HTHS viscosity ≥ 2.9 mPa × s., But very limited proportions of ingredients that could adversely affect the permeability of the particle filter. Sulphated ash content ≤ 0.5% m / m.
- C2: Mid-SAPS oil with reduced HTHS viscosity ≥ 2.9 mPa × s, limited proportions of ingredients that could adversely affect the permeability of the particle filter. Sulphated ash content ≤ 0.8% w / w.
- C3: Mid-SAPS oil with a higher HTHS viscosity ≥ 3.5 mPa × s, with limited but higher proportions of combustion-residue substances such as sulphate ash, phosphorus, sulfur. Sulphated ash content ≤ 0.8% w / w. Total Base Number (TBN) ≥ 6 mg KOH per g.
- C4: Low-SAPS oil with a higher HTHS viscosity ≥ 3.5 mPa × s, with more limited proportions of ingredients that could adversely affect the permeability of the particle filter. Sulphated ash content ≤ 0.5% m / m. TBN ≥ 6 mg KOH per g.
ACEA C1 oils have a greatly reduced HTHS viscosity, which can help save fuel, and are better for the diesel particulate filter because they do not clog it as much; however, oils according to ACEA C1 do not have as good lubricating stability as other oils (ACEA C3 / C4) of this specification. As a rule of thumb, C1 is better for the diesel particulate filter, C3 is better for the engine.
Unalloyed motor oil
In the early days of motorization, motor oil was basically unalloyed - and the engines did not have effective oil filtering . However, even after a short period of operation, every engine oil carries with it oil-insoluble foreign substances, which consist of material abrasion in the engine, combustion residues, road dust and aging residues of the oil itself.
The usual oil change intervals for cars at the time were between 1000 and 5000 km, depending on the engine design and manufacturer. Depending on the manufacturer's operating instructions and the typical field of application of the engine, the complete oil pan had to be dismantled and cleaned with every or every second oil change . In classic cars, unalloyed motor oil is still important today, as the DD additives contained in the alloyed motor oil would prevent the formation of the oil sludge. The unwanted foreign matter would be bound in the oil and regularly pumped through the engine's oil circuit, which would increase mechanical wear on bearings and cylinder running surfaces and reduce the lubricating effect of the oil. To make matters worse, the detergents contained in the oil with additives have a strong cleaning effect. In this way, they prevent the oil carbon deposits that are often required in older engines, which are more or less included in the design, or they dissolve deposits that have already formed, which can lead to blockages in the oil ducts and thus to engine damage. Such deposits are often ascribed a sealing effect - if they are removed by aggressive additives, the engine may have to be completely dismantled and resealed. That is why there are still unalloyed single-grade and multigrade engine oils, the area of application of which is primarily limited to engines without a full-flow oil filter.
Alloyed motor oil
Almost every modern motor oil is additive, i.e. alloyed. Even before the First World War, the first miracle cures appeared, which were supposed to improve the quality of commercially available motor oils. In addition to many useless products, there was always one or the other additive (oil additive) that proved to be quite effective under certain conditions. That was not hidden from the military either. The American military finally published the first oil specification during World War II, which was based on adding additives to the base oil. The so-called HD engine oil (HD stood for Heavy Duty) was standardized for the first time and soon found its way into the civil engine oil test regulations. Today, there are up to 20% of an engine oil of additives such as aging inhibitors , detergents , dispersants , corrosion inhibitors , metal deactivators , antioxidants , Pourpointverbesserern , friction modifiers , foam suppressors , wear reducers and viscosity index improvers . At the same time, the engine oil filters continued to develop. The Purolator has been around since 1923, but it still allowed over 90% of the engine oil to flow by unfiltered. It was not until 1943 that the first fully effective full-flow oil filters were developed. The twist-on filters, which are still used today, have been around since 1954 and enable simple, regular replacement of the filter cartridge. These filters hold the foreign matter carried along by the engine oil and store them until the next filter change. This means that the oil sludge pan in the oil pan, which was previously necessary for the design, has become superfluous, the inside of the engine can be kept much cleaner during operation, which ultimately benefits the low wear and tear, but also reduces internal resistance and thus fuel consumption. These developments are mutually beneficial, so that modern engine oils with their special alloys made from base oils and additives allow oil change intervals of up to 50,000 km and more if the vehicle or engine manufacturer has approved the appropriate long-life oils.
Low-friction engine oils have been developed to reduce mechanical friction losses in order to save energy, i.e. fuel. For this purpose, extremely thin-bodied engine oils are combined with high-quality additives in such a way that an adequate supply of lubricant to the engine can be ensured despite the low engine oil viscosity. Practically all multigrade oils with a low temperature viscosity of 0W or 5W are designed as synthetic or semi-synthetic low-viscosity oils. Low-friction engine oils can actually save fuel in connection with the engine technology matched to them. In order to avoid engine damage, the use of such low-viscosity oils should, however, be restricted to engines whose manufacturers have given appropriate approval. The manufacturer's approval is often printed on the outer packaging of the low-viscosity oil. If the engine or vehicle manufacturer specifies or suggests engine oils with a low-temperature viscosity of 0W or 5W in the operating instructions, it can be assumed that they have tested the lubricity of such low-viscosity oils and found it to be good.
Long-life engine oils are synthetic low-viscosity oils. They are prescribed for vehicles with computer-calculated long-life service and must never be supplemented or topped up with other engine oils if the service intervals and guarantee conditions are to be observed. If "normal" engine oil is to be used in a vehicle that has been designed for long-life service, the engine control unit must be set to fixed oil change intervals. "Longlife" is also the name of an oil specification.
Motor oil with solid lubricant
It is generally recognized that solid lubricants made of aluminum , graphite , ceramic , copper , molybdenum sulfide or PTFE can develop better lubricating properties when added to lubricating greases compared to purely petroleum-based products. It is controversial whether they can also develop this in connection with engine oil. Both supporters and opponents point to scientific studies and technical test reports that confirm their respective views.
Up until the 1940s, there was a barely manageable number of oil additives that were used to improve the quality of commercial motor oils. When the American military had alloyed oils tested and standardized as heavy-duty oils in the early 1940s, oil additives gained recognition. Possible advantages of solid lubricant motor oils are the better emergency running properties and the higher lubricity. The latter should reduce the frictional resistance in the engine and thus lead to more power and less fuel consumption. The selected type of solid lubricant offers more individual properties. Most vehicle and engine manufacturers formulate a prohibition on the use of external oil additives in their operating instructions, which can lead to the loss of any manufacturer's guarantee in the event of engine damage. Manufacturers state that some of their solid lubricant engine oils are suitable for vehicles with catalytic converters. Via the prescribed crankcase ventilation , particles of the engine oil get through the combustion chamber of the engine into the exhaust system, so that oil vapor and its combustion products must not damage the components of the exhaust system.
A motorcycle oil is little different from an oil for automobiles. However, on many motorcycles the clutch and transmission are integrated in the engine, so that there is only one oil circuit. This results in a particularly high requirement for shear stability (motorcycle engines achieve higher piston speeds than car engines) and also for stability against surface pressure, since the lubrication of the gearwheels places different demands on the oil than the lubrication, e.g. B. the crankshaft in the engine. While an adhesive film of lubricant can build up on rotating engine parts, it is literally crushed by the grinding gears in the gearbox and pushed out of the tooth flanks. This extreme pressure load is countered with high pressure additives that are not contained in motor oil for cars or only in small quantities.
Some engine principles (e.g. pump-nozzle direct diesel injection) also require an increased amount of high-pressure additives or EP additives in the valve train area. This is taken into account by the engine manufacturers in their approvals.
Many motorcycles have wet clutches that run in the oil bath of the engine oil. Such oil bath clutches do not tolerate additives to reduce the coefficient of friction, which are contained in many modern car and low-viscosity oils. While the focus is on saving fuel in everyday cars, it is more important for a motorcycle to use an engine oil that can withstand high speeds and high temperatures, as the amount of oil used in motorcycle engines is comparatively small and the temperature peaks during operation are often higher than in cars . For these reasons, motorcycles with an oil bath clutch and / or integrated manual gearbox may only use engine oil that is clearly classified as suitable by the manufacturer.
Belt in an oil bath
Some scooters have toothed belts running in the transmission's oil bath. Ford EcoBoost engines have the timing belt run in the oil bath of the engine oil. This requires oils that will not degrade these belts.
Many tractors (almost all modern tractors with continuously variable transmissions) use different oil circuits for the engine, transmission and hydraulic system, similar to those used in automobiles. The requirements and specifications are therefore also similar. Above all, tractors with powershift transmissions and older tractors have a common oil circuit for the gearbox, rear axle and hydraulics, with wet multi-plate clutches running in the oil bath. This results in special requirements that cannot be met with standard oils. In such machines, a universal oil Super Tractor Oil Universal (STOU) is usually used, which meets the requirements of axle and gear oils (API GL4 with Limited-Slip (LS) additives), engine oil and those of a hydraulic oil. The determination of the purity classes according to ISO 4406, SAE 4059 is not or only with great difficulty possible with this oil, since the relatively large additives are also counted with the classic particle counting using a light source ( laser ) and photodetector . A corresponding evaluation can only be done arithmetically.
For gas engines , oils are partially optimized for gas operating conditions.
Reasons for this are:
- Liquid fuels vaporize and cool the mixture through their enthalpy of vaporization . This cooling effect does not apply to gas operation, so that the combustion and thus the oil temperatures are higher.
- The additives added to the liquid fuels, for example for cleaning the combustion chamber, are missing from the gas. The engine oil then has to take on this task. The additives required can - depending on the formulation of the oil - result in an increased ash content in the exhaust gas, so that a closed particle filter is more heavily loaded.
The successor organization of the CCMC - the ACEA ( Association des Constructeurs Européens d'Automobiles ) - is an interest group of the European automotive industry. Since the beginning of the 1990s, engine oil classifications for European vehicles have been developed and published there, taking into account the usual US test runs and the API classifications in order to ensure that the results can be transferred.
- ACEA Class A - engine oil for gasoline engines in passenger cars
- ACEA Class B - engine oil for diesel engines in passenger cars and light commercial vehicles
- ACEA Class C - engine oil for gasoline and diesel engines with new exhaust gas aftertreatment systems (e.g. diesel particulate filters)
- ACEA class E - engine oil for diesel engines in commercial vehicles and trucks
The class is supplemented by a numerical code. Example: an A1 / B1-04 would be an engine oil for gasoline engines (class A) and diesel engines (class B) in standard quality (1), tested according to the ACEA classification issued in 2004 (-04).
From the numerical value, however, in no way can one infer the value of the oil. An A3 or B3 classified oil is more valuable than an A1 or B1 oil. An A1, B1 or C1 oil is an oil with a reduced HTHS viscosity. Due to the reduced friction, a fuel saving of approx. 2.5% is achieved compared to a 15W-40. It is not correct that a C3 is therefore of higher quality, but a class C1 engine oil burns with fewer residues than a class C3 engine oil - if a C3 oil was used instead of the prescribed C1 oil, the particle filter could clog.
The former CCMC classifications (CCMC D, CCMC G, CCMC PD etc.) have expired and are no longer being checked
The American Petroleum Institute (API) is the largest advocacy group for the US oil and gas industry. Since the 1940s, they have been developing technical standards and issuing technical guidelines, including for engine oil.
- API - S ( S ervice or S park plug ignition = spark ignition): For gasoline engines in passenger cars, valid standards are currently API - SJ and API - SL. API - SM has been on the market since 2007 to meet increased requirements for low-viscosity oils and exhaust gas standards.
- API - C ( C ommercial or C ombustion ignition = compression igniter = compression ignition): for diesel engines in commercial vehicles and trucks, currently valid standards are API - CF and API - CI-4 for four-stroke diesel engines and API - CF-2 for two-stroke diesel engines .
- API - GL = gear oil
All older letter or number codes are no longer valid. Nevertheless, they are still used and identified for special engine oils, e.g. B. in engine oils for vintage and veteran vehicles.
Diesel engines in cars are rarely found in the USA. Therefore there are no special test standards for their engine oil.
ILSAC together with JAMA and others
Motor oils according to the specification of ILSAC (International Lubricant Standardization and Approval Committee), JAMA (Japan Automobile Manufacturers Association) and others are common in Asia.
- ILSAC GF 1 is roughly equivalent to API - SH
- ILSAC GF 2 roughly corresponds to API - SJ
- ILSAC GF 3 roughly corresponds to API - SL
- ILSAC GF 4 is roughly equivalent to API - SM
This Japanese organization JASO (Japanese Automotive Standards Organization) also issues its own oil specifications. The JASO specifications for two-stroke oils and the JASO specification T 903 from 1999 are important. In this - based on the API / ACEA specifications - certain requirements for Otto four-stroke motorcycle engines are checked. All motorcycle oils tested in accordance with JASO T 903 must meet special lubricant properties that are important for motorcycle engines with integrated gears. This test pays special attention to the shear rate (HTHS viscosity), shear, evaporation and viscosity stability at high temperatures. In addition, special coefficient of friction requirements are checked in order to determine which oil is suitable for oil bath clutches. After that, denotes the class
- JASO MA oils with a high coefficient of friction, which are recommended for oil bath clutches and
- JASO MB oils with a low coefficient of friction that should not be used for oil bath clutches.
ACEA together with Alliance, EMA and JAMA
What is special about the global specifications of the Association des Constructeurs Européens d'Automobiles (ACEA), Members of the Alliance of Automobile Manufacturers (Alliance), Engine Manufacturers Association (EMA) and Japan Automobile Manufacturers Association (JAMA) is that the test runs take place in parallel with American, Asian and European vehicle engines.
- Global DLD 1, Global DLD 2 and Global DLD 3 are test standards that were specially developed for light commercial vehicles with diesel engines.
- Global DHD 1 is a test standard that was specially developed for heavy commercial vehicles with diesel engines.
Special standards from vehicle manufacturers
Some vehicle and engine manufacturers have published their own specifications, which are generally based on an ACEA or API classification. Special practical driving tests and road tests are also often prescribed.
The in-house standards of the following vehicle manufacturers are particularly important on the German market:
- Mercedes Benz
- Opel (GM-LL (−2010), dexos (from 2010))
- VW (Audi, Seat, Skoda)
With the increasing technical maturity of modern engines, the demands on engine oils and their properties have also changed. The use of simple oils in newer vehicles (or, conversely, modern oils in older engines) can potentially cause problems.
Modern filter systems such as soot particle filters need special, residue-free combustion engine oils. However, these are unsuitable for many older engines because their lubricating properties are insufficient there. A new VW standard is designed to be downward compatible - but not generally: Some older engines with pump-nozzle injection technology are explicitly excluded.
If vehicles with internal combustion engines are frequently operated on short journeys, the oil dilution often leads to wear and tear, with an accompanying increase in oil. Unburned fuel is dragged into the engine oil and is not evaporated out again due to the low oil temperatures in short-distance traffic.
In gasoline engines, oil increases due to frequent cold starts, which means that the fuel is deposited on the cold cylinder walls and gets into the oil.
In diesel engines with diesel particulate filters , when the particulate filter regeneration is necessary, additional fuel is injected into the combustion chamber during the expansion stroke in order to increase the exhaust gas temperature; however, the fuel does not burn completely and ends up in the engine oil. The ADAC examined the phenomenon of oil dilution, especially in diesel engines with particle filters. Based on this investigation from 2009/2010, he demanded:
- “ The vehicle manufacturers are called upon to further develop particle filter regeneration processes that do not require any shortening of the oil change intervals even in short-distance operation and ensure that the vehicle is fully usable without any disadvantages. "
- “ The vehicle manufacturers and authorized workshops should offer their customers attractive oil change offers - especially for diesel short-haul drivers. Oil prices of 25 to over 30 euros per liter are unacceptable. "
Short-distance traffic should be avoided for the reasons mentioned above, as otherwise the combustion engine will not reach its optimal operating temperatures (cooling water and engine oil) or only for a short time. Some PSA diesel engines use a special fluid to regenerate the particulate filter, which is injected directly into the exhaust system.
In Germany, sellers of motor oils are obliged by the waste oil ordinance to take back used motor oil. Waste oil can rarely be given to the municipal waste disposal company free of charge. Some auto repair shops and petrol stations accept used oil if you are known as a customer.
- Christian Jentsch: Chemical additives in motor oils . In: Chemistry in our time , 12th year 1978, No. 2, pp. 57-62
- Richard Michell: Practical Guide Oil. For engines, transmissions and axles of all years . Heel Verlag, Königswinter 2012, ISBN 978-3-86852-611-0 .
- Liqui Moly engine oil FAQ
- Questions and answers about engine oils from ADAC
- Basic concepts of lubrication / technology from MOTUL ( Memento from April 11, 2009 in the Internet Archive )
- Engine oil codes explained
- ↑ SAE codifies new oil viscosity grade (SAE 16) ( Memento of the original from April 4, 2013 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. , accessed October 2013.
- ↑ ADAC: Motoröl - Classifications and Specifications ( Memento of the original from April 4, 2015 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. (PDF; 83 kB) on adac.de , accessed on June 26, 2019.
- ↑ https://www.acea.be/ (Ed.): 2012_ACEA_Oil_Sequences.pdf .
- ↑ Motor oil guide: With these tips you will lubricate your car perfectly , focus from December 12, 2014.
- ↑ Questions and answers about engine oil . ADAC info.
- ↑ Wolfgang Richter: Wie lubricated , Technology Review of November 4, 2011.
- ↑ https://www.youtube.com/watch?v=0U1aLQdKJjU
- ↑ Richard Backhaus: "Lubricants must be multi-talented" . In: MTZ . No. 2015-08-07 . Springer Vieweg, Springer Fachmedien, July 1, 2018, ISSN 0024-8525 , interview with Rolf Luther, Fuchs Schmierstoffe GmbH, p. 2 , pp. 22-24 .
- ↑ Oil dilution for diesels with a particle filter . At adac.de , accessed on June 28, 2019
- ↑ Waste Oil Ordinance as amended on February 22, 2012 (PDF; 52 kB) Accessed on July 22, 2013 .