Loading icon
Post banner image
Oil 10w 40: characteristics, features

The decoding of the SAE 10w40 marking indicates the performance of a universal lubricant, which, due to its high characteristics, is considered the most common of those available in stores today.

It is used in different types of engines, protects the contacting parts from wear. To decipher the marking, you need to imagine what semi-synthetic motor oil is, what it is intended for.

  • Indicators of semi-synthetics
  • Lubrication indicators 10w40
  • The difference between 5w40 and 10w40
  • Comparison with other lubricants
  • 10w30
  • 5w30

  • Indicators of semi-synthetics

    Motor oil by origin can be: mineral, synthetic or semi-synthetic. All motor oils of different types differ from each other in their own technical characteristics, which are determined by the motor oil test, as well as in the scope of use.

    Separately, it is worth noting the division of oils by viscosity. The classification is called SAE. It is accepted everywhere, it is used by car manufacturers when creating cars. Depending on the viscosity of the engine oil, it can be:

  • for winter. Has a letter "w" and the number in the marking. The minimum temperature limit is prescribed at which the car oil does not change its own properties (pour point);
  • for summer. Only a number is written on it, which means how harsh operating conditions the car oil can withstand;
  • for any season. The best option. Perfectly protects the motor in heat and frost. This is what oil is supposed to be. 10w 40.
  • Semi-synthetic oil is a lubricant that is obtained by mixing mineral water and certain synthetic elements. It is effective, useful, not much worse than synthetic.

    Typically, semi-synthetic motor oils are used in engines that have worked a lot and may differ in their power from modern power units. In such engines, synthetics burn out.

    It should be noted that synthetic lubricant has certain advantages. It better protects the engine in conditions of high / low temperature and load, provides an optimal level of oil viscosity at any speed.

    Might be interesting: Changing the oil in the engine "Daewoo Nexia"

    Synthetic lubricant is chemically stable, therefore, retains its benefits for quite a long time. Despite this, semi-synthetic motor oil is perfect for ordinary drivers, because it is universal and inexpensive.

    Synthetics or semi-synthetics - it does not matter much. Lubricants of both types have optimal technical characteristics and perform well in used cars and in different climates, because they necessarily pass many oil tests.

    Lubrication indicators 10w40

    10w 40 can be poured into both gasoline and diesel engines. 10w 40 decoding says that:

  • by origin oil 10w 40 semi-synthetic. They can be used in winter and summer;
  • semi-synthetics 10w 40 begin to freeze at minus twenty degrees. If the temperature is higher than specified, the oil retains its own properties, guarantees a quick start of the engine;
  • The upper temperature threshold of 10w 40 oils (high-temperature viscosity of motor oil) is plus thirty-five degrees. This means that the lubricant can be used in places where the temperature does not exceed the specified one.
  • A competent choice of motor oil will make it possible to ensure good functioning of the power unit, its easy start-up, and also perfectly protect rubbing parts from wear and damage. 10w 40 oils should:

  • good protection against wear. This is the main purpose of the car oil. The quality of protection depends on the additives. The most important parameter is the viscosity index;
  • prevent the formation of deposits in high and low temperature conditions. This characteristic depends on the number of additives and the quality of the main liquid;
  • resist oxidation. This means that SAE 10w 40 does not oxidize when in contact with oxygen;
  • save fuel. Engine oil 10w 40 in winter and summer can reduce friction of parts against each other and reduce engine power loss;
  • do not form a lot of soot. This is especially significant if the lubricant is poured into the diesel engine;
  • have approvals from popular car manufacturers, making it possible to pour motor oil into cars of certain brands.
  • Semi-synthetic 10w40 is perfect for those who need an oily fluid that ensures the functioning of the internal combustion engine in almost any climate as efficiently as possible.

    This might be interesting: Oil Elf 10w 40, reviews, price, semi-synthetic

    The difference between 5w40 and 10w40

    A variety of lubricants are used for long and trouble-free operation of engines. What kind of oil product should be poured into the engine so that it works reliably?

    Might be interesting: The best engine oil for Honda (Honda)

    The more similar the numbers and letters in the markings of different lubricants, the more difficult it is to understand, for example, how 5w40 oils differ from 10w 40.

    The letter indicated in the marking indicates the all-weather lubricant. The first number indicates how well the oil performs in low temperature conditions. By the second digit it is possible to understand what is the high temperature viscosity of the oil.

    Motor oil 5w40 or 10w 40 is optimally suited for four-stroke gasoline/diesel/turbocharged engines installed in passenger cars.

    5w40 consists of elements that ensure unchanged operational parameters for a fairly long period. The use of 10w40 or 5w 40 increases the service life of the motor. The internal combustion engine does not get dirty with oil and does not need frequent cleaning.

    5w40 is low-volatile, removes carbon deposits, does not deform sealing parts, but protects the engine somewhat worse in hot conditions than 10w40, because it is more liquid. In view of this, it is recommended to use “five” in winter, and “ten” in summer.

    Comparison with other lubricants


    What is the difference between "thirty" and "forty"? The first is not recommended to fill in very hot conditions (above twenty-five degrees).

    "Sorokovka" perfectly tolerates high temperatures. In any case, if you live in moderate climates, then 10w30 and 10w 40 are a great option (you can mix them, by the way).


    5w30 differs from 10w40 in that it is more suitable for winter than for summer. It can provide protection for the power unit at a temperature not lower than minus thirty degrees, while the "magpie" is recommended for use at a temperature not lower than minus twenty-five degrees.

    For some Russian regions (especially in the North), this is a rather important factor, because an unsuitable lubricant can simply freeze.

    Also, many are interested in whether it is possible to mix different oily liquids, that is, dilute one car oil with another. If we are talking about two mineral / synthetic / semi-synthetic lubricants, then you can.

    Might be interesting: Classification of motor oils according to SAE

    However, if the description of the vehicle (operating manual) states otherwise, the oils must not be mixed. And, of course, two grease additives that are completely different in origin and available additives cannot be mixed (usually they differ greatly in color).

    By pouring two incompatible oily fluids into automotive equipment, you will not break your engine. However, you still have to drain the resulting lubricant, as it will not be able to properly protect the power unit and ensure its quick start.

    The engine will simply wear out, not work at full power. Simply put, you won't be able to travel comfortably. In addition, wear sooner or later leads to malfunctions in the motor, serious damage.

    So you shouldn’t take unnecessary risks; it’s better to use the lubricant recommended by the car manufacturer. This is due to the fact that an oil test is the most reliable guarantee that the oil will suit your car.