What is the Engine Oil Grade Chart?

[KingstonLee]

Automotive engine oil grades are classified based on two major indicators: the viscosity index SAE and the quality index API. Below is an introduction to the classification of engine oil grades: 1. Classification according to SAE viscosity grades: 1. There are 6 types of winter engine oils: 0W, 5W, 10W, 15W, 20W, and 25W. The "W" stands for Winter, and the smaller the number before it, the greater the fluidity of the oil and the lower the applicable temperature. 2. There are 5 types of summer engine oils: 20, 30, 40, 50, and 60. The larger the number, the higher the viscosity of the oil, the stronger the high-temperature protection performance, and the higher the applicable temperature environment. 3. There are 16 types of all-season (winter and summer) engine oils: 5W20, 5W30, 5W40, 5W50, 10W20, 10W30, 10W40, 10W50, 15W30, 15W40, 15W50, 20W20, 20W30, 20W40, and 20W50. 2. Classification according to API quality grades: 1. The API quality grades divide engine oils into the S series and the C series. 2. The S series indicates gasoline engine oils; the C series indicates diesel engine oils. 3. When labeled with both S and C, it means the oil is suitable for both diesel and gasoline engines. Each series is sorted by letters (A, B, C, D, E, F, etc.), and the further back the letter, the higher the grade and the better the performance.