Synthetic motor oils with a viscosity of 5w 30. How to correctly decipher the labeling of motor oils. How to choose motor oil

The large number of products and diversity on the fuel and lubricants market has recently been the main reason why selecting motor oil involves certain difficulties. Car enthusiasts constantly focus attention not only on quality, but also on issues of seasonality, mixing, compatibility and interchangeability of oils of different brands.

It is also well known that the lubricant viscosity index is one of the key parameters along with basic basis, used in the manufacture of lubricant (). In other words, the quality and price of the product will depend on the base and additive package.

As for viscosity, this parameter determines both the general possibility of using a lubricant in a particular engine, taking into account the recommendations of the power unit manufacturer itself, and the advisability of operating an internal combustion engine on a product with a particular viscosity.

In this article we intend to talk about the popular 5w30 and 5w40 oils, what is the difference between these products, what are the characteristics of 5w30 and 5w40 oils, is it possible to fill in 5w40 oil instead of 5w30, and also which oil is better, 5w30 or 5w40 in winter and summer.

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Viscosity and seasonality of motor oil

Let's start with the fact that many drivers have heard and some have encountered a situation where in winter the engine cannot be started due to the fact that the lubricant has become very thick in the crankcase. This means that with a charged and fully functional starter, it is still not possible to crank the crankshaft at the required frequency required to start.

It turns out that in this case the material has too high a viscosity and is not suitable for use in winter conditions. In other words, the so-called seasonality of fuel and lubricants for the engine was not taken into account. This is not surprising, since today there is no clear division between summer and winter products.

The entire modern classification of oils comes down to the fact that the driver can choose a product from catalogs of all-season motor oil. Such lubricants They have different viscosities, tolerances, base stocks and additive packages. Moreover, recently there has been an increasing practice of using , which can be equally poured into both gasoline and diesel engines.

So, let's return to the conditional classification by season:

1. Without going into details, the so-called summer lubricant has a high viscosity index, which allows the material to work normally in the engine when outside temperature does not drop below zero. At the same time, a more viscous product forms a “thick” protective film on the parts, reliably protecting surfaces from wear.
2. Winter lubricant has a low viscosity; such a lubricant allows you to start the engine in severe frosts without much difficulty. However, a more “liquid” low-viscosity substance forms a thin protective film after warming up the internal combustion engine, inferior in quality to engine protection compared to its summer counterparts.
3. All-season engine oil, unlike winter and summer, does not require seasonal replacement, that is, it does not need to be changed seasonally and can be used year-round. Considering that almost all modern products are all-season, such products represent the optimal balance, combining the necessary properties for summer and at the same time suitable for winter operation

In order to separate lubricants based on the dependence of viscosity on temperature, there is a special classification according to SAE (a specification that was developed by the Society of Automobile Engineers). The SAE classifier defines summer products as ranging from 20 to 60. Winter lubricants are rating from 0W or 5W to 25W.

The combination of these two indicators is separately indicated on all-season oil and is well known to car enthusiasts (for example, oil 0W20, 5W30, 10W40, etc.). Now let's figure out what the viscosity of the popular oils 5w30 and 5w40 is, as well as what exactly the decoding of 5w30 and 5w40 oils will mean. Let us add that the topic of choosing 5w30 or 5w40 oil for a vehicle requires the same answers to the questions posed in this article.

What is the difference between 5w30 and 5w40 engine oil?

In order to accurately determine the viscosity of all-season lubricant in winter and summer period, you need to look at the numbers before and after the letter W in the designation. The indicated letter is an abbreviation for Winter. For example, 5W30 means that 5W indicates the SAE viscosity grade at subzero temperatures.

The number 30 is the SAE temperature rating in relation to the product's properties at high temperatures. These two specifications will determine both the ease of starting, fluidity and pumpability of unheated lubricant in winter, and the stability of the protective film on the surface of loaded parts at maximum temperatures.

If you ask yourself how 5w40 oil differs from 5w30, then it should be noted that these oils have identical indicators that characterize their suitability for use in winter. The 5W classification clearly indicates that this oil ensures reliable starting of the internal combustion engine down to -30 degrees below zero.

Now let's take a look at the high temperature viscosity according to SAE, that is, the difference between 5w30 and 5w40. A general comparative analysis of the data indicates that the kinematic viscosity of 5W30 when heated to 100 degrees Celsius ranges from 9.3 to 12.5 mm sq./sec. At the same time, 5W40 under similar conditions has a viscosity index from 12.5 to 16.3 mm sq./sec.

From this comparison it is also clear that the minimum HTHS viscosity in the case of 5W30 is 2.9. At the same time, for 5W40 this value is also 2.9, while the parameter can reach 3.7, which is noticeably higher.

The above data allows you to determine which oil is thinner, 5w30 or 5w40. In simple words, under high-heat conditions, 5W40 is noticeably different from its 5W30 counterpart in high-temperature viscosity. Otherwise, the answer to the frequent question of which oil is thicker, 5W40 or 5W30, will be the first option, that is, 5w40.

Which oil is better: 5w30 or 5w40 in summer

Considering that 5W40 oil is more viscous, it creates a strong and stable oil film on the surface of parts compared to its competitor. As it may seem at first glance, such a product is no different during winter operation and better protects the engine in summer.

Note that this statement is only partially true. First of all, you need to consider design features of one or another internal combustion engine, as well as individual recommendations of the engine manufacturers. The fact is that even a slight increase in oil viscosity in some units can lead to worse pumpability, that is, lubricant will not reach the friction pairs in the required quantity.

Also, when choosing a summer viscosity value, you should take into account the fact that too “thin” lubricant (for example, 5w30) can lead to lubricant leaks through oil seals, gaskets and other seals. When using low-viscosity oils, the oil film on parts may turn out to be thin, as a result of which the wear of components significantly increases and the temperature of the internal combustion engine increases.

In other words, before choosing 5W40 or 5W30, you must:

1. Separately, make sure that both types of oil are on the list recommended by the manufacturer for a particular engine.
2. It would also be a good idea to take into account the operating features of the engine.

For example, a viscosity index of 30 means that the declared characteristics of the motor oil will be maintained at operating temperatures only up to 150 degrees.

If the car is located in a region where the outside air temperature rises significantly in summer, the driver constantly “turns” the engine to high speed, practices an aggressive riding style and heavily loads power unit, then the oil temperature will be as high as possible. In this case, it is worth thinking about increasing the “summer” viscosity index.

Compatibility of 5w30 and 5w40 oils

Quite often, especially in the event of an emergency malfunction, it becomes necessary to add oil to the engine. In such a situation, the lubricant of the same manufacturer whose product was originally poured into the power unit is not always at hand.

The same is true for the viscosity index. For this reason, it is important to know whether 5w30 and 5w40 oil can be mixed. At the very beginning, we note that it is often not particularly recommended to mix mineral oils with products in which the base is completely synthetic. In other words, mineral water cannot be mixed with synthetics. It is also not recommended to mix semi-synthetics with synthetics, etc.

As for 5W30 and 5W40, it is theoretically possible to mix these oils with minimal risks if both products are from the same manufacturer. In an emergency, mixing oils is allowed different manufacturers, but only taking into account that they have the same basic basis.

This means that mineral oil mixes only with mineral, semi-synthetic with a similar product, etc. At the same time, it is still impossible to give an unambiguous answer to the question of whether it is possible to add 5w40 to 5w30 oil. The fact is that for each type of oil, manufacturers use special additive packages that can react after mixing.

In any case, even if there are no obvious consequences after topping up, it is still an emergency measure. After eliminating the breakdown, you must immediately drain such mixed lubricant from the engine. Also in some cases it may be necessary additionally.

Let's sum it up

Taking into account the above, it becomes clear that the viscosity of the oil and the stability of this characteristic at different temperatures determines the main characteristics of the lubricant, as well as the price of the product.

The best choice can be considered an oil in which the viscosity indicators are within the tolerances of the engine manufacturer. At the same time, you should pay attention to the base, since a more expensive semi-synthetic oil, for example 5W40, will be better in service life and quality compared to the same, but mineral 5W40.

For owners of old cars, the choice of oil must be approached with special responsibility. On the one hand, there is an intensive development of technologies in the production of fuels and lubricants. This means that the information regarding lubricants in the instruction manual may be very out of date.

Moreover, if you have to select the lubricant yourself, you need to take into account a number of features that we described above. To put it simply, expensive low-viscosity synthetics will not always mean that an old engine using such a modern high-tech oil is reliably protected in summer and winter.

Finally, we add that when choosing an oil, you need to adhere to a certain middle ground, and also take into account the individual characteristics of the operation of the internal combustion engine. This means that the lubricant should not dilute greatly and lose its properties, taking into account the maximum possible heating, and also remain fluid with the onset of cold weather.

Read also

Features of selecting engine oil for winter. Which all-season oil is considered winter according to the labeling, what should you consider when choosing.

Motor oils are oils that are used to lubricate pistons and rotors in internal combustion engines. Today they represent a base fluid with additives that increase parameters. Distillates and residual elements from different index viscosities (hydrocarbon components), their mixtures, synthetic substances (ethers, olefins). The main part of all-season lubricants is produced by thickening a low-viscosity base with macropolymers.

What is required from motor oils

Automotive lubricant is an important part of the internal combustion engine. It is capable of performing its task for a long time and reliably, providing a certain engine life only if its indicators are fully consistent with the temperature, chemical and mechanical influences that it endures in the car’s lubrication complex. Description of the basic requirements for motor oils:

• Good cleaning characteristics against various contaminants, which ensures the cleanliness of engine elements;
• Wear resistance, which is achieved by a durable oil film and optimal viscosity;
• No corrosive effects on internal combustion engine components;
• Resistance to aging, the ability to cope with external influences, minimally deteriorating your performance;
• Compatibility with seals and catalysts;
• Low foaming;
• Low volatility, low waste consumption.

Certain lubricants have special requirements. For example, lubricants that are thickened with macropolymer additives must have the required resistance to thermal degradation. For energy-saving lubricants, antifriction and good rheological characteristics are important.

How oils are classified by origin

IN depending on chemical composition, as well as the method of manufacturing the base, lubricants are divided into a couple of broad subgroups - mineral and synthetic. Mineral oil liquid is made from petroleum through distillation. Synthetic is produced through organic synthesis, also petroleum-based, but with more complete processing of the base substance.

There are also semi-synthetic lubricants. Semi-synthetics are made by adding synthetic elements to mineral oil. Semi-synthetics is not an entirely correct name; it would be more correct to say “mineral with added synthetic elements.”

Decoding 5w30

Often, when purchasing motor oils, car owners do not understand what the meaning of 5w30 is. What does this data about oil indicate? For which cars is it advisable to use it? In order to fully decipher the marking oily liquid, a special base has been created.

The lubricant is divided according to its scope of use according to the API (Petroleum Institute). On the back of the canister, the API designation does not indicate quality, but the operating characteristics. For example, the letters S or C indicate that the lubricant should be used in a gasoline/gas engine. That is, if semi-synthetics or synthetics of the A3/B3 category resemble API SL/CF in properties, then its use exclusively in turbocharged engines is irrational.

For such power units, semi-synthetic oil with low viscosity and excellent environmental characteristics is optimal. In view of this, a lubricant such as ACEA A5/B5 is common among many motor manufacturers today. This oil can outperform API SM/CI-4 in many respects. It is no secret that with the right choice of ACEA oil fluid, the likelihood of the need for a complete overhaul of the power unit is reduced.

There is also motor oil marked ISLAC. It indicates that the product was manufactured in accordance with the requirements of the US-Japan Committee. Therefore, the data set is the same as the API. For example, ISLAC GL-2 is almost identical in performance to API SL.

What if you need to buy energy-saving lubricant for your own car? This oil makes it possible to significantly reduce fuel costs. According to the parameters “High temperature/high shear viscosity”, this oil is used for operation in high temperature conditions. In other words, if the engine temperature becomes more than one hundred degrees Celsius, the following increases:

• Oil viscosity index;
• Oil film thickness;
• Fuel costs.

When using an energy-saving lubricant, the viscosity under similar operating conditions is lower than that of ordinary oil, but the oil film is thinner. In addition, the car owner should be aware of the possibilities of using lubricant at different temperatures.

Value 5w30

The Russian Federation is a large state, in some parts of which there is extreme cold, in others there is unbearable heat. In view of this, technical specifications Every car owner needs to know the oils.

5w30 oil is marked according to a special SAE system. Based on the marking, it is possible to determine the temperature at which it must be used. According to SAE 5w 30 it is intended for use in winter time, however, it can also be used in summer. The definition of 5w30 engine oil is as follows:

• The first number tells you what the lower temperature limit is at which the properties of the oil (for example, viscosity) do not change. “5” means that this lubricant can be filled if the air temperature is not lower than minus thirty degrees. It also shows how smoothly and at what speed the lubricant will flow through the oil complex to the working surfaces, and how much energy will be spent;
• The letter indicates what time of year it is recommended to use the lubricant. “w” – preferably used in winter conditions;
• The last number shows the maximum temperature at which the oil can be used normally (if the temperature of the power unit is not more than one hundred degrees). “30” means that the oil can only be used at temperatures up to plus twenty-five degrees.

We took three fully synthetic imported motor oils with SAE 5W‑30 viscosity from leading manufacturers that occupy the lion's share of the domestic market - ExxonMobil, Shell and Castrol. To this trinity they added the not so common, but no less well-known Motul oil.

How did you experience it? Using each of the oils, a specially prepared bench engine was spun in specified modes for one hundred and twenty hours, while its characteristics were compared at various stages of testing. The engine is a domestic eight-valve VAZ-21114 with injection, with a modified control program and an oil cooling system for the pistons.

Why is the engine not a foreign brand? Test conditions do not allow. The technique requires opening the engine before and after testing, measuring, checking defects, photographing and weighing parts. But modern non-Ukrainian engines cannot be disassembled or reassembled - the crankshaft cannot be removed. More precisely, you can remove it, but putting it back is already prohibited.

After a fixed time, we took samples of the oil - three times - to assess the rate of its aging. Changes in the physical and chemical parameters of the oil, as well as the content of wear products in it, were monitored. And opening the engine clarified the idea of ​​​​deposits and wear.

To eliminate doubts about possible counterfeits, we sent fresh oil samples to the laboratory to determine basic physical and chemical parameters and compared them with the indicated manufacturers. If they match, it means the oils are real, not fake. Another thing surprised me: the initial parameters of all four oils are almost the same. Are they from the same barrel? From different ones! This was discovered after measuring the dynamic viscosity over the entire temperature range. But first, let’s remember what viscosities generally exist.

KINEMATIC, DYNAMIC AND HTHS

There is a direct relationship between oil viscosity, friction losses and wear rate of the friction unit. In classical hydrodynamics, two viscosity characteristics are distinguished - dynamic and kinematic. It is the dynamic viscosity of the oil that is important for the engine, since it takes into account the change in density depending on temperature. And kinematic viscosity is important for oil workers; it can be accurately determined by a capillary viscometer. Previously, the viscosity parameters prescribed by the SAE class limited only the possible range of changes in the kinematic viscosity of the oil at a temperature of 100 °C. This range for SAE 30 oils is 9.3–12.6 cSt; for SAE 40 oils it is wider than 12.6–16.3 cSt.

Now the SAE classification is supplemented by restrictions on dynamic viscosity at 150 °C. This is the so-called high-temperature viscosity HTHS (High-Temperature, High-Shear).

Previously, it was believed that the SAE classification was enough to select an oil, but then it turned out that it was not enough. Oils from the same group at operating temperatures can differ in viscosity by tens of percent, and this is essential for engine operation. That is why an additional restriction was introduced.

Manufacturers of modern oils are guided by opposing priorities. Thus, Shell claims the low viscosity of Helix Ultra oil, which determines low friction losses. And Motul has specially developed 8100 X-clean FE oil, which claims a high HTHS value. Who is right?

To complete the picture, we will go through all temperatures - from winter to fully operating modes, like a fully warmed-up engine. The highest values ​​of high-temperature HTHS viscosity at the first test are found in Motul 8100 X-clean FE oil, as promised by the manufacturer: 3.2 mPa s versus 2.7 mPa s for Mobil. The run-up is almost 20%! This means that this oil will reduce the load on the bearing by 20% - or will increase the pressure on the bearing by the same 20% without worsening its operating conditions. The price for this is the highest values ​​of dynamic viscosity at low temperatures: 8330 mPa s for Motul oil versus 6220 mPa s for Mobil oil. This means that in the Arctic and Antarctic regions it will be more difficult to start an engine with Motul oil.

However, it is more interesting to trace the dynamics of changes in this parameter throughout the entire period of testing. Mobil 1 ESP Formula and Motul 8100 X‑clean FE oils changed their parameters slightly and quite predictably during 120 hours of torture with a Russian engine and Russian (not the best, as everyone says) fuel. During testing, dynamic viscosity over the entire temperature range increased by only 3–5%.

But Castrol Edge FST and Shell Helix Ultra oils changed their viscosity by 21–28%! Moreover, the increase in viscosity of Castrol oil began almost immediately - such dynamics are uncharacteristic of the usual behavior of the oil. And Shell oil held up well until the middle of the tests, but gave up in the second half of the cycle. As a result, by the end of the tests, the advantage that these oils had over Motul oil in terms of viscosity at low temperatures completely disappeared. For those who plan to use these oils in harsh northern conditions, there is something to think about.

An even more expressive picture reflecting the rate of aging of oils is provided by an analysis of the dynamics of changes in kinematic viscosity at 100 °C.

And again: with Motul oil the viscosity remains virtually unchanged. For Mobil oil, the change in viscosity is more noticeable, and by the end of the test period it reached a threshold value. But Castrol produced a very significant increase in viscosity at 100 °C, jumping far beyond the permissible limits. The most interesting thing is that the viscosity at 40 °C began to decrease towards the end of the tests - this can be seen from the data in the final table. The viscosity index has gone as high as 210!

Viscosity index is important parameter motor oil, which characterizes the rate of change in viscosity with increasing temperature. The higher it is, the smaller the difference between viscosities at high temperatures and at low temperatures. For full synthetics it usually lies in the range of 160–180.

And another strange thing about Castrol oil. Usually the alkaline number gradually decreases: a complex of detergent additives is activated. But here, on the contrary, growth!

It is possible that calcium or another element is returned to the oil from deposits formed in the engine, to which the device reacts. By the way, for the other three oils the same method gave the expected result.

We assessed the energy saving of oils twice, comparing it in the modes of our cycle with both fresh oil and 120 engine hours used. These results are also summarized in tables.

Here again it is appropriate to return to the conversation about HTHS. Oil with the most high value HTHS - Motul 8100 X‑clean FE - also shown here best result. However, judging by the results, all tested oils can easily be classified as energy-saving. But those with a lower viscosity growth rate had the least change in fuel consumption and engine power after the cycle long-term tests. The effect of high-temperature viscosity was most clearly manifested when analyzing the protective functions of the oil. Analysis of the content of wear products in oil samples selected at the final stage of testing clearly reveals the unconditional leadership of oils with high HTHS. This is Motul 8100 X‑clean FE. Quite understandably: higher viscosity means greater thickness of the separating layer and less .

Opening the engine after the test cycles showed approximately the same final level of high- and low-temperature deposits, while more stable oils gave a slightly better result. But in general, all oils showed high results in these parameters, typical of high-quality synthetics.

NOT FOR RUSSIA?

Why did the oils perform differently during the tests? Two of them - Motul 8100 X-clean FE and Mobil 1 ESP Formula - worked without any problems, while the other two showed not so optimistic results. The very nature of oil aging, when the viscosity begins to decrease, but other parameters generally remain normal, most often indicates that the additives included in the used additive package are in conflict with something.

By undertaking this examination, we wanted to continue the topic of “oil plague” that we raised three years ago - unpredictable decomposition of oil, which produces black tar in the channels of the lubrication system, oil pan, and valve mechanism. This disease has killed more than one hundred engines. And oil workers named Russian gasoline as one of the possible culprits of this disaster. Then we found other causes of the “plague”, which were confirmed by experiment. But it was necessary to check the version about the influence of bad gasoline.

The solution was found after our examination of cheap 95 gasoline (ZR, 2015, No. 5), during which it turned out that most of them contain prohibited methanol. This is exactly the gasoline we used for our tests.

Thus, our research has confirmed that bad gasoline can really ruin the oil, and with it the engine. Yes, but Motul 8100 X-clean FE and Mobil 1 ESP Formula oils, running on the same gasoline, did not express any complaints about it! This means that the additive package can be adjusted so that the oil works normally under our conditions. Another thing is that not everyone succeeds.

In the meantime, we repeat: drive around unchecked gas stations in a wide circle! When it comes to choosing motor oil, we recommend choosing products with a higher HTHS value.

The motor, nerves and wallet will be more intact!

Among car owners, the most popular brands are considered to be 5w30 and 5w40 motor oils, but not many people know the difference between them and what the oil marking means. This is an important question, so it’s worth figuring out which oil is better.

What does the marking of 5w30 and 5w40 motor oil mean?

So, the first number from the oil marking indicates its viscosity under conditions low temperatures, the second part means the fluidity of the substance in the warm season. This marking of engine oil characterizes it according to the common SAE classification.

The numbers in the marking indicate the type of oil - both types are all-season, which is why it is so popular among motorists. This class lubricating fluids It is universal (all-season) and can be used in engines with any type of fuel at any temperature.

Decoding oil 5w30 and 5w40

Viscosity at low temperatures. The viscosity parameter has a very great value for the machine, since it determines the ability of the lubricant to remain on the surface of the motor for a long time. The most important property of motor oil is described by part 5 of the 5W index, and W means winter. In cold weather, engine oil thickens. The stronger its viscosity, the more force it works oil pump. In these types of oil, the marking has the same first index.

High temperature viscosity. This parameter characterizes the second part of the marking. According to the established SAE classification for grade 5w30 at t 100 °C, the viscosity of the substance will be from 9.3 to 12.6 mm kV/s. For brand type 5w40 from 12.6 to 16.3 mm kV/s. Also, the high-temperature viscosity of the lubricant is characterized by another important indicator: minimum viscosity at shear rate (106 s-1). For 5w30 oil this figure is lower (2.9) than for 5w40 oil, for which this figure is (3.50).

The decoding of 5w40 engine oil is quite simple:

1) 5W indicates the low-temperature viscosity of the substance and allows the car to be started at -35 °C.

2) Subtract 40 from the number in front of W. As a result, the resulting number (-35 ° C) will be the minimum oil temperature, which will allow the internal combustion engine pump to pump it through the system, maximizing the lubrication of the parts.

With such mathematical manipulations, you can easily determine the lowest “cranking” temperature of the engine. The interpretation of 5w30 oil indicates that this parameter is -30°C. This is not difficult to determine: we subtract 35 from the engine starting temperature (5 °C) and it becomes obvious that lowering the oil temperature leads to an increase in its viscosity, and it becomes quite difficult for the starter to crank the engine.

Which engine oil is better 5w30 or 5w40

Motor oil in a car is used for the sole purpose of forming a rich oil film on interacting engine parts. There are very small gaps between such parts in the motor (only a few microns), which require constant high-quality lubrication. Only the manufacturer knows which brand of lubricant is most suitable for each car.

Manufacturing companies, when recommending the use of a certain type, first of all take into account the design features of the power unit itself, and based on these indicators, the characteristics of the oil. Therefore, when choosing oil, it is recommended to follow the manufacturer's instructions.

It is important to consider that, in addition to the common SAE classification, all lubricants must also meet the requirements of the API and ACEA systems. The oil marking according to these classification systems is indicated on the packaging, but does not attract the attention of car owners.

As for popular brands of oil 5w40 or 5w30:

1) Grade 5w40 effectively holds the film, completely eliminating dry friction of parts. It is ideal for modern units with high thermal stress.

2) Oil marked 5w30 has a much lower viscosity and is indispensable in cold weather, as it simplifies engine starting, but in hot weather it becomes too fluid. Under conditions of t 120 – 140 °C in the engine, the viscosity of 5w40 oil is 50% higher than the viscosity of oil marked 5w30.

Engine oil 5w30 or 5w40 – how to choose

It is worth noting that cars with different years of manufacture have their own recommendations regarding the most optimal choice of engine oil. Experts recommend using 5w30 oil if your car is more than seven years old and its mileage does not exceed 70,000 kilometers.

If the car's mileage exceeds this figure, 5w40 oil should be filled in, which is due to the fact that over time the gaps between the elements that make up the engine increase. Therefore, if you previously used oil with a low viscosity, you should switch to 5w40. In addition to viscosity, these motor oils differ in the number of additives.

Professionals also recommend monitoring the car’s reaction to different engine oils. The machine itself will tell you which oil is best suited. For example, on some models of power units, 5w30 oil often cannot withstand increased speeds (torque), which disrupts the stability of its operation. To avoid such situations, it is recommended to use the lubricant with the thickest structure.

Compatibility of 5w30 and 5w40 oils

There are situations when, in the event of a malfunction, it is necessary to urgently add oil to the engine. As a rule, the lubricant of the exact manufacturer whose product was originally poured into the engine is not always nearby.

The same applies to the oil viscosity index, and therefore you should know whether oils labeled 5w40 and 5w30 can be mixed. It is worth noting that it is often not recommended to mix oil with a fully synthetic mineral oil base oil. It is also not recommended to mix synthetics and semi-synthetics, etc.

As for lubricants marked 5W30/5W40, theoretically these liquids can be mixed with minimal risks only if they are both products from the same manufacturer. Mixing products from different manufacturers is allowed only in an emergency situation, but taking into account that they must have the same basic basis.

From this we can conclude that semi-synthetics are mixed only with semi-synthetics, mineral oil is mixed with a similar product, etc. However, it is impossible to answer unequivocally the question of whether it is possible to add a seemingly analogous 5w30 to an oil marked 5w40, since for For each type of lubricant, manufacturers use their own additive packages, which, after mixing, can react.

Even if there were no consequences in case of emergency topping up of liquids, this is an emergency measure that cannot be used constantly. After eliminating the breakdown, it is necessary to immediately drain the mixed lubricant from the motor and be sure to change oil filter, and in some cases it may even be necessary to additionally flush the engine before changing the oil.

Let's sum it up

When choosing motor oil, you have to choose a product of one brand or another, and not only the quality of the engine, but also other significant parts of the car often depends on it. Professionals recommend using oil with a higher viscosity, since its use better protects engine parts. Oils of the 5w30 and 5w40 brands are a reliable assistant to the car engine.

Their differences are insignificant; these types of oil are of sufficient quality and meet all European requirements. Using high-quality oil will protect the car’s power unit from breakdowns and allow you to save on repairs or replacement of the engine.

The most popular of all the presented fuels and lubricants is 5w30 synthetic motor oil from the world's leading brands.

The main and main task of lubricants is to protect engine parts from running dry and to ensure normal work under conditions of complete sealing of the working cylinders. Properly selected motor oil is the key to proper engine operation and increases the service life of its components.

The fuel and lubricants market is represented by three product categories:

• for cars with gasoline engines;
• for diesel units;
• universal, which have physical characteristics that allow them to be used in engines internal combustion and diesel engines.

According to seasonality of use, lubricating fluids are distinguished:

• winter – 5w, 10w
• summer,
• all-season – 0w 30, 5w30

Regardless of the category of lubricant, motor oil has main parameter physical properties that determine its effectiveness. This is viscosity (5w30), that is, the ability of a lubricant to maintain fluidity while remaining on the surface of parts. The protection of parts from friction and wear during vehicle operation depends on this indicator. If the viscosity (5w) does not correspond to the recommended one, then the engine life is reduced. The second indicator (30) is also of great importance - this is high-temperature viscosity. Its deviations from the recommended may cause the engine to major renovation faster than originally planned. Since in this case the engine operates at higher speeds, which can take it out of the range of maximum permissible standards.

When choosing a lubricant, you need to take into account the viscosity index. It should not exceed the parameters recommended by the manufacturer. Otherwise, you will increase the load on the engine, which can lead to serious damage and subsequent expensive repairs.

How to make the right choice?

What should you pay attention to when choosing universal fuels and lubricants for your car?

1. Viscosity index.

• The ability to start the engine in winter conditions depends on it. The lower this indicator, the easier the engine obeys the ignition signal.
• The degree of coverage of engine parts with lubricant in order to prevent friction and wear, as well as to prevent chemical and mechanical damage, depends on the viscosity.

1. Temperature regime.

• It determines the minimum threshold for the effectiveness of using a given type of lubricant in the cold season.
• It also sets the temperature range at which the use of oil fluid guarantees safe operation of the vehicle when the engine heats up.

This classification of fuels and lubricants according to viscosity and temperature regime established by the American Society of Engineers SAE. The compliance of motor oils with this classification is indicated on each package “sae”.

Series 5w 30

The most popular of all the presented fuels and lubricants is synthetic motor oil of the 5w30 series. The characteristics of the products of this group meet the stringent requirements for vehicle operation in cities and on highways. City mode is different:

• long-term idle work motor,
• car idling in traffic jams,
• stable trips over short distances,
• increased dust content in the airspace.

These factors significantly reduce the service life of engines. A correctly selected oil product is the key to long-term operation and technically sound condition of the engine.

Automotive lubricants sae class 5w30 is distinguished by a unique formula based on the synthesis of an oil base and a package of additives that are characteristic of synthetics, providing:

• protection of the engine from friction and wear of parts,
• resistance to oxidative processes during operation in conditions of high humidity and climatic precipitation.

The additive package may vary. They all perform only their specific functions. It is a balanced set of additives that makes the oil base suitable for use in any particular type of engine. In each specific type of lubricating fluid, the conformity of additives must be within the framework of the standards for the quality of motor oils.

It should be noted that changes in the heating temperature of the motor can change the properties of lubricating components. Depending on the intensity of its work, motor oils of the sae 5w30 class can heat up to 150 °C. When choosing engine oil, you must rely on the technical specifications recommended by the car manufacturer. Oil approval is not given for a specific car brand, but directly according to the engine type. Therefore, the brand of oil fluids can be any, but the main parameters of the lubricant must meet the requirements set by the manufacturer of your car.

Buying synthetic or mineral motor oil with sae 5w30 is a purely personal matter. This depends on the age of the car, engine characteristics and operating conditions. Some are inclined to believe that cars older than 5 - 7 years accept mineral lubricants better, as this reduces oil consumption and increases engine life. In this case, it is better to opt for increased viscosity.

For vehicles with new generation engines and foreign production synthetic ones are recommended for use motor fluids. From this series, synthetic motor oils of the sae 5w30 class are in greatest demand, as they satisfy climatic conditions and traffic intensity in urban format.

Replacing lubricant

The frequency of replacing lubricant in a car depends on operating conditions, mileage, and the condition of engine parts. Most best option– 10 thousand km. In difficult conditions of use, this period can be reduced to 7 - 8 thousand km. mileage With a dual fuel format, for example “gasoline - gas”, the replacement period increases to 15 - 20 thousand km. This is due to the fact that gas fuel is a more environmentally friendly product and is gentler on the parts of the unit. It is necessary to monitor the quality of engine oil in the engine and its quantity once every two weeks. For this purpose, cars have a special dipstick indicating the minimum and maximum oil level.

Classification and standards

Synthetic motor oils sae 5w30 meet environmental requirements. All representatives of this group not only have SAE, ACEA and API compliance, but are also certified for use in vehicles with valve petrol and diesel engines from such large manufacturers, like: BMW, VOLVO, RENAULT, MAN. To obtain approval from manufacturers, all oil products undergo strict control and numerous tests. All declared characteristics must comply with the manufacturers' requirements.

SAE - classification of lubricant products by viscosity (5w);

ACEA is a European classification based on the set of additives and the quality of the final product.

API is an American classification of fuels and lubricants by engine type. Separates the purpose of the oil for use in gasoline (SJ) and diesel (CF) engines. The absence of this information indicates an outdated quality class.

Advantages of choosing 5w30 synthetics

Thanks to its technical composition, 5w30 synthetics has the following advantages:

• enhanced protection of internal engine parts from mechanical and chemical influences;
• provide heavy-duty film coating of engine parts from the inside;
• protective properties against oxidation and corrosion;
• protective functions in relation to the moving parts of the motor from mechanical friction and wear during operation;
• greater time range between engine oil change procedures;
• universal lubricant composition 5w30 allows the use of liquids of this class in different types power units.

Synthetic sae 5w 30 is a demi-season lubricant, which allows it to be used all year round. There is no need to change the oil according to seasonal changes. At the same time, it does not lose its properties and remains effective for any engines.

Synthetics 5w 30 CF series for diesel engines

Synthetic low ash motor oil 5w 30 is designed for diesel cars and is equipped with a double exhaust gas purification system. This category complies with state standards for environmental friendliness of lubricating fluids. Recommended for vehicles with particulate filters, turbocharging and catalysts. Complies with the latest API SN/CF, ACEA C3 requirements.

In the production of 5w 30 diesel motor oils, modern basic components are used, developed using new nanotechnologies. They increase protective functions and reduce the amount of waste emissions. Synthetic additives have a reduced content of sulfur, phosphorus and chlorine bonds.

5w30 motor oils have characteristics recommended for filling into diesel engines with particulate filters and turbines:

• keep the working unit clean;
• provide quick access to engine parts;
• maintain normal operating pressure in the engine at any load level;
• guarantee durable lubrication at low and high temperatures;
• reduce fuel consumption;
• reduce the amount of exhaust gases.

Diesel engine oils sae 5w 30 guarantee high vehicle performance and increase service life gas neutralizers. Car manufacturers allow the use of synthetic sae 5w 30 with the specified properties, which maintains preferential conditions for vehicle maintenance during the warranty period.

Modern lubricants have the ability to reduce fuel consumption. Being a universal lubricant, motor oils are used both in new generation cars and in older models of global automakers. One of the significant indicators in choosing a lubricant is its compliance with all necessary regulations and standards.