VISCOSITY OF OILS 5W-20, 0W-20
The viscosity of an oil is the resistance to shear between layers of a liquid, it depends on temperature, with an increase in temperature, the viscosity decreases and vice versa. The less the viscosity of the oil changes with temperature, the higher the viscosity index. Learn more here that can i use 0w20 instead of 5w20.
For engine oils, the following types of viscosity are distinguished: kinematic viscosity (unit of measurement cSt or mm2 / s) and various dynamic viscosities (unit of measure mPa * s): CCS, MRV and HTHS. It is these types of viscosities that formed the basis of the international classification of SAE J300 oils.
If you look at the oil canister, it will show the viscosity according to SAE J300: 0W-20, 5W-20, 5W-30, etc., and in the same form, the permissible viscosities for use in a car will be indicated in the owner's manual. But still, there are cases when the automaker does not indicate a complete list of viscosities, and in this case it is important to understand what the numbers in the SAE J300 viscosity mean.
The first digit after the letter W (SAE 0W-, SAE 5W-…) characterizes the low-temperature viscosity class, the lower the number, the better the low-temperature properties of the oil and the lower the temperature the engine can start. The second digit (SAE ..- 20, ..- 30, ...) is the high-temperature viscosity class, it already characterizes the viscosity at the engine operating temperature and the thickness of the oil film, that is, the larger the second figure, the more viscous the oil at the engine operating temperature ...
For example, oils 0W-20 and 5W-20 have the same high-temperature viscosity class, which means they have the same viscosity in a warm engine, but at the same time, 0W-20 oil has an advantage, because its low temperature properties are much better.
For engine oils, the following types of viscosity are distinguished: kinematic viscosity (unit of measurement cSt or mm2 / s) and various dynamic viscosities (unit of measure mPa * s): CCS, MRV and HTHS. It is these types of viscosities that formed the basis of the international classification of SAE J300 oils.
If you look at the oil canister, it will show the viscosity according to SAE J300: 0W-20, 5W-20, 5W-30, etc., and in the same form, the permissible viscosities for use in a car will be indicated in the owner's manual. But still, there are cases when the automaker does not indicate a complete list of viscosities, and in this case it is important to understand what the numbers in the SAE J300 viscosity mean.
The first digit after the letter W (SAE 0W-, SAE 5W-…) characterizes the low-temperature viscosity class, the lower the number, the better the low-temperature properties of the oil and the lower the temperature the engine can start. The second digit (SAE ..- 20, ..- 30, ...) is the high-temperature viscosity class, it already characterizes the viscosity at the engine operating temperature and the thickness of the oil film, that is, the larger the second figure, the more viscous the oil at the engine operating temperature ...
For example, oils 0W-20 and 5W-20 have the same high-temperature viscosity class, which means they have the same viscosity in a warm engine, but at the same time, 0W-20 oil has an advantage, because its low temperature properties are much better.
For example, in many Hyundai cars the use of SAE 5W-20 viscosity oil is indicated and many car owners are looking for this particular viscosity, but even if the SAE 0W-20 viscosity is not indicated in the owner's manual, then it can be used in this car and show better properties since the high-temperature viscosity class is the same, SAE 20, that is, the viscosity of the oil in a warm engine will be the same for SAE 5W-20 and SAE 0W-20 oils, while the low-temperature properties of SAE 0W-20 oil are better.
There is a widespread belief that SAE 0W-20 oil is used only in winter, but this is not the case, SAE 0W-20 oil is an all-season oil, its component composition provides better performance in both summer and winter compared to SAE 5W-20 viscosity. Even if in a particular region there are high temperatures in summer,
Therefore, if the instruction manual indicates the use of a viscosity of 5W-20, then 0W-20 can be used, if the viscosity is 5W-30, then an oil with a viscosity of 0W-30 can be used, thereby improving the low-temperature properties of the oil.
The number at the letter W affects only the low-temperature properties of the oil, the second figure already affects the operating viscosity. This is very important for the correct selection of lubricant.
There is a widespread belief that SAE 0W-20 oil is used only in winter, but this is not the case, SAE 0W-20 oil is an all-season oil, its component composition provides better performance in both summer and winter compared to SAE 5W-20 viscosity. Even if in a particular region there are high temperatures in summer,
Therefore, if the instruction manual indicates the use of a viscosity of 5W-20, then 0W-20 can be used, if the viscosity is 5W-30, then an oil with a viscosity of 0W-30 can be used, thereby improving the low-temperature properties of the oil.
The number at the letter W affects only the low-temperature properties of the oil, the second figure already affects the operating viscosity. This is very important for the correct selection of lubricant.