What is the meaning of gear oil 80w90

Gear oil is used to lubricate various gears in transmissions, reducers and differentials, which can prevent tooth surface wear, scratches, sintering, etc., extend service life, and improve transmission power and efficiency. Gear oils have different types and grades. Different grades of gear oils are selected according to the harshness of the gear working conditions. Some gear oils are marked with 80w90. What does gear oil 80w90 mean?

Gear oil 80w90 is a kind of viscosity grade identification. At present, the viscosity classification of vehicle gear oil in my country adopts SAE viscosity classification, which can be divided into 7 viscosity grades: 70W, 75W, 80W90, 85W90, 85W140, 90, 140. SAE is a gear oil viscosity grade classification standard established by the American Society of Automotive Engineers. W means low temperature gear oil, 80 means low temperature viscosity, the smaller the number, the smaller the viscosity, the better the fluidity, and the stronger the low temperature performance, 90 means The higher the high temperature viscosity, the higher the number, the higher the high temperature viscosity and the higher the temperature resistance.

In addition, the American Petroleum Institute has divided the API performance of gear oils, which can be divided into performance levels such as GL-1, GL-2, GL-3, GL-4, GL-5, and GL-6. There is also a corresponding logo. Among them, GL-1, GL-2, and GL-3, which are heavily loaded, have been eliminated on the market, and currently GL-4 and GL-5 are commonly used in family cars. The level of GL-5 is higher than that of GL-4, and the price of GL-4 is lower than that of GL-5. Compared with GL-4, GL-5 contains more sulfur and is more acidic. The general manual wave family car is more suitable for GL-4 transmission oil.