How are engine oil grades classified?
1 Answers
The classification of engine oil grades is as follows: 1. Classification according to SAE viscosity grades: (1) There are 6 types of winter oils, 5 types of summer oils, and 16 types of all-season oils. (2) The 6 types of winter oils are 0W, 5W, 10W, 15W, 20W, and 25W. 'W' stands for Winter, and the smaller the number before it, the greater the fluidity of the oil and the lower the applicable temperature. (3) The 5 types of summer oils are 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. (4) The 16 types of all-season oils are 5W20, 5W30, 5W40, 5W50, 10W20, 10W30, 10W40, 10W50, 15W30, 15W40, 15W50, 20W20, 20W30, 20W40, and 20W50. 2. Classification according to API quality grades: (1) API quality grades divide engine oils into the S series and the C series. (2) The S series represents gasoline engine oils; the C series represents diesel engine oils. (3) When labeled with both S and C, it indicates that the oil is suitable for both diesel and gasoline engines. (4) Each series is sorted alphabetically (A, B, C, D, E, F, etc.), with letters further in the alphabet indicating higher grades and better performance.