What does SL5W40 oil mean? The SL5W40 represents the oil label, where SL represents the quality level of the oil, S means the oil engine oil, and L indicates that the quality of the oil is L. 5W can simply understand that the freezing point of motor oil is minus 30 ° C. Among them, W represents winter, 5 represents minus 25 ° C. 40 means that when the oil is at 100 ° C, the motion viscosity standard is between 12.5mm2/s and between 16.3mm2/s, which means that the standard range of the viscosity of the oil at 100 ° C. The SL5W40 engine oil can be understood as the level SL level, the freezing point is -30 ° C, and the gasoline engine with higher viscosity.
In fact, the label of the car oil is based on foreign standards. The meaning of the specific representatives is as follows:
“SL” is an abbreviation API oil grade logo from the American Petroleum Association. The beginning of “S” represents oil engine oil, and then the alphabets behind will start after the letters A. SA, SB, SC, SD, SE , SF, SG, SH, SJ, SL, SM, SN, which represent different oil quality levels. As the alphabet increases, the higher the quality level of the oil. Now there are newly launched, and the level has reached the SP -level engine oil.
The latter “5W40” is generally identified as “5W-40”, which is an English abbreviation from the American Automobile Engineer Association. In fact, the label has not changed, but just adds a sign of SAE. In “5W40”, W means the abbreviation of English word Winter (winter), which can be expressed as the meaning of winter motor oil, and the minimum temperature of the environment that can be used with 5W. That is, the freezing point of the oil, 5 corresponds to -30 ° C. In fact, it actually represents the low temperature resistance of motor oil. The oil will rarely freeze.
Then “40” represents the motion viscosity standard of the motor oil at 100 ° C from 12.5mm/s to 16.3mm/s. It represents a motion viscosity standard range at 100 ° C. The larger the number, the larger the motion viscosity range. 50 motion viscosity standards are between 16.3mm/s and 21.9mm/s; and 30 motion viscosity standards are 9.3mm/s to 12.5mm/s. In fact, it represents a standard range of the viscosity of motor oil. In fact, there is no difference in quality and bad. You can choose according to the needs of the vehicle engine.
Then look at the specific low temperature resistance of the number in front of W. From the start of the number 0 to the end of the interval from 5 to 20, 0W corresponds to -35 ° C, 5W corresponds to -30 ° C, 10W corresponds- 25 ° C, 15W corresponds to -20 ° C, and 20W corresponds to -15 ° C. The smaller the numbers, the better the performance of the oil resistance to the low temperature. However, 20W corresponds to minus 15 degrees Celsius, and most of the domestic areas will not generally and do not have such a low temperature. Of course, the selection is still based on the needs of the engine to refer to the extremely low temperature.
Based on the relevant instructions of the above oil label, the SL5W40 oil is actually given the corresponding label of the oil. Including the corresponding applicable gasoline engine, quality level, and the motion viscosity range at low temperature to 100 ° C. In the actual choice of vehicle oil, it is still based on the maintenance manual or the oil label of the car manufacturer.
The label of the oil, except for the quality level, can represent the quality of the oil to a certain extent. Other parameters mainly represent the relevant standard scope of the oil compliance. However, the quality level of motor oil is also updated with the improvement of oil production technology and the requirements of engine technology. The choice of engine oil is mainly based on the engine needs to choose the engine oil. Do not blindly choose high -marked engine oil. Using unsuitable oil, it will affect the normal operation of the engine.
What does SL5W40 oil mean? Represents the level of motor oil and the applicable temperature range