SAE is the abbreviation of American Society of Automotive Engineers, and SAE grade represents the viscosity grade of engine oil. SAE30, SAE40 and SAE50 are single-stage oils, while SAE 10W-30, SAE 15W-40 and SAE 20W-50 are multi-stage oils. Among them, the smaller the number before "W" means that the lower the low-temperature viscosity is, the better the protection ability of the engine during cold start; The number after "W" is the index of high temperature resistance of oil. Please refer to the following table for specific use temperature:
Suitable climate for lubricating oil:
API is the abbreviation of API specific gravity, and API grade represents the classification of engine oil quality. It uses a simple code to describe the working ability of oil.
API engine oil is divided into two categories: "S" series stands for gasoline engine oil; "C (commercial vehicle)" series represents diesel engine oil; When the letters "S" and "C" exist at the same time, it means that the oil is commonly used in gasoline and diesel. If "S" is in the front, it is mainly used for gasoline engines. On the contrary, it is mainly used in diesel engines.
From "SA" to "SM", with each additional letter, the performance of engine oil will be better than the previous one, and there will be more additives in engine oil to protect the engine. The lower the letters, the higher the quality level.
At present, most oil products on the market are SF grade or above. For example, Great Wall Jinjixing gasoline engine oil (SL 5W40) is APISJ grade, while Great Wall Jixing gasoline engine oil (15W/40) is APISG grade, indicating that Jinjixing's quality grade is higher than Jixing's. At the same time, the greater the numerical difference before and after W indicates that the comprehensive performance of engine oil is getting better and better, which is what we usually call the difference between synthetic oil and mineral oil, because the greater the numerical difference before and after W indicates the greater the temperature span, for example, there is a 5-degree difference between 15W/40 and 10W/40 at low temperature, which means that the starting performance of 10W/40 is better in the same environment.
SJ level is not high, according to the oil classification standard, I'd better stick something to you first.
API stands for api gravity's evaluation standard of engine oil quality grade. S stands for gasoline engine oil. L stands for grade, from API SA, SB, SC, SE, SF, SG, SH, SJ, SL, the lower the letter, the higher the oil grade. C stands for diesel oil. F stands for grade, from API CA, CB, CC, CD, CE, CF, CF-4, CG-4 and CH-4, the lower the letter, the higher the grade of oil. SAE stands for American Society of Automotive Engineers (abbreviation) regulation on viscosity grade of lubricating oil. 5W indicates the service temperature range of oil products, ranging from 0W, 5W, 10W, 15W, 20W, 25W, etc. The smaller the number, the better its low-temperature fluidity, and it can work better at low temperature. 40 represents the viscosity of engine oil at 100℃, and the brands are SAE 20, 30, 40, 50 and 60. The higher the number, the higher the viscosity. 5W50 is commonly known as multi-grade oil. It shows that the viscosity of the oil meets the requirement of 5W at low temperature, the viscosity of 100℃ meets the requirement of No.40, and "5W40 SL/CF" shows that the oil has good fluidity at low temperature and meets the requirement of 5W. At 100℃, its viscosity is in the range of 40, which has the performance of SL grade of gasoline engine and CF grade of diesel engine. It is a pure synthetic lubricating oil, which can be used in winter and summer.