Viscosity of engine oil: table. Test of engine oils

Often decide which engine oil is better, based on the viscosity parameter. Let's try to answer questions about it. Why is this indicator so important? What classification is used to determine the viscosity of the engine oil? Table, which clearly shows the different viscosity classes, given in the article, will help to make the right choice when buying lubricant.

What is it for?

It is clear that the main task of lubrication is to reduce friction between the elements of the mechanism, creating a film on them and thus helping to maintain tightness. Other functions are extremely important, for example, strengthening the cooling system, as well as absorbing the extracted chips from parts, dust and dirt.

The engine can overheat from thermal and mechanical processes occurring in a continuous mode during its operation. Lubricating fluid, spreading through the entire mechanism, removes heat from it.

The garbage that oil collects in the course of its work increases the life of the power unit.

Naturally, these tasks will be fulfilled the more successfully, the better the used lubricating fluid. One of its main useful characteristics is viscosity. What it is and how to choose the oil in accordance with it, we will consider in more detail.

Chemical composition

Lubricating fluid is divided by its chemical composition into mineral, semi-synthetic and synthetic.

Mineral is obtained by distilling oil and is considered a natural product. It is cheaper and more often used on cars with mileage than on new vehicles.

Synthetic, on the contrary, completely artificial oil. It is the most expensive, because it best preserves its useful qualities, due to the presence of many additives for various purposes that improve its performance.

Semisynthesis is obtained as a result of mixing of mineral and synthetic bases. This is the best option for the ratio of price and quality. Of course, it will not be possible to obtain such a product on its own, as high-tech equipment is used for its creation. If some enthusiasts decided on such experiments, then as a result they had to change the motor.

After understanding the chemical composition, you can go to the most interesting indicator, the fluidity of the lubricating fluid.

Viscosity is ...

In addition to the oil base, as mentioned above, the most important characteristic is the ability to fluidity of the lubricant and maintain its consistency regardless of the weather conditions. The temperature changes, especially in recent years, are very sharp, and if the lubricating fluid is not adapted to these processes, then the engine will not be easy. Such a property, that is, a level of utility as a function of temperature, is fluidity.

In the world, the classification of motor oils according to viscosity is adopted, which reflects the individual classes according to this characteristic. In accordance with it, there are oils summer and winter.

Winter oils have in the name the letter W, which means winter, that is "winter". The temperature range at low rates is especially important. After all, it is thanks to him that the vehicle is operated safely in the cold season.

Hot weather, as a rule, oils are tolerated without problems.

Separately, it should be said about the so-called all-season lubricating fluids that appeared in recent years. They are easy to recognize by double numbers, where on the one hand the winter limit is indicated, and on the other - the summer one.

The preferences of many car enthusiasts show which engine oil is better. Today, synthetic all-weather liquids have become most widespread.

How to use oils

Theoretical knowledge, of course, matters. But motorists are usually more interested in questions of a purely practical nature, for example, what viscosity to pour engine oil into the engine. In order to easily understand this, use a special classification called SAE. The specific viscosity of the engine oil is determined here. The table, where all the data is laid out, helps to easily understand what level is required for a particular car. The interpretation of the values in it is not difficult.

Viscosity of engine oil: table

It can be seen from the table that, at high temperatures, a technical fluid with a thicker consistency is required, and at low temperatures, a liquid one is required.

Note that the higher the index, the greater the viscosity of the engine oil. The table below will complete the idea of the possibilities of all-weather events.

Right choice

In order not to be mistaken with lubrication, it is necessary first of all to follow the recommendations of the car manufacturer. Normally, the operating instructions describe in detail all the characteristics that engine oil must meet, including the required viscosity level.

Besides this, of course, the nature of the vehicle's operation is also important.

Often, domestic consumers acquire the all-weather 10W40, and in recent years also 5W30 or 5W40.

At normal temperatures from minus twenty to plus twenty, the first option will be optimal, where use is possible from minus thirty to plus forty. Then starting the motor will always be easy and safe for him.

The limiting minus temperature is determined very simply: from the first number it is necessary to take forty. Thus, in oil 10W40, from 10 we take forty and get -30. That is, with this lubricant, you can safely use the car at temperatures up to minus thirty degrees.

If the temperature often drops below thirty, then it's better to use 5W30 or 5W40. Then the motor will be easily launched and in such difficult conditions.

If the choice is incorrect

It happens that the lubricating fluid is not used in the operating conditions for which it is intended. It is clear that such a service will not pass without a trace on the engine. The situation is fraught with the following negative consequences.

1. If the viscosity of a synthetic engine oil in winter is not sufficient, then due to excessive density it will not immediately be taken to work after starting the engine. Therefore, for some time, the friction between the parts will be dry, which will lead to overheating and rapid aging of the unit.
2. If too hot oil is used in the heat, it will not be able to hold onto the parts and cover them while working with the film. Because of this, there comes the so-called oil starvation, which is fraught with the most unpleasant consequences for the engine.

That is why when choosing the oil it is so important to use the necessary viscosity class of motor oils for various operating conditions.

Motor oil grades

Today the market of lubricating fluids is simply huge. Usual motorist is easily lost in all products offered by manufacturers with various additional additives, washes and other.

At the vehicle manufacturer, oils from specific manufacturers are often recommended. If you are not particularly versed and do not want to delve into this topic, the easiest way is to take advantage of their advice and buy those brands that are offered. However, of course, the main thing that drives car companies in this matter is commercial interest. Often they simply enter into contracts with the producers of oils to advertise their products. Therefore, it is more appropriate to use other ways of choosing a lubricating fluid.

Test of engine oils

Interesting are some product reviews that can be found in the media. If the test of motor oils is carried out by independent publications, sometimes it is useful to study to determine the choice of brand.

If you stopped at something and started using this oil, it's best not to change it anymore and put only one brand in the engine. It is known that when replacing from five to ten percent of the used fluid remains in the engine. If after that, pour oil of another brand, it is not known how the additives of one and the other lubricant behave in the chemical reaction. Therefore, if you care about your engine, it's better not to take chances.

On the other hand, if, nevertheless, any test of motor oils convinced you of the need to use a certain brand, it is advisable to flush the engine with the same oil that you will then fill it with.