What is the API grade of engine oil?
1 Answers
API engine oil is divided into three categories. The following is the relevant content introduction: 1. The "S" series: Represents oil for gasoline engines, with specifications including: API SA, SB, SC, SD, SE, SF, SG, SH, SJ, SL, SM, SN. 2. The "C" series: Represents oil for diesel engines, with specifications including: API CA, CB, CC, CD, CE, CF, CF-2, CF-4, CG-4, CH-4, CI-4. 3. When both "S" and "C" letters are present, it indicates that the oil is suitable for both gasoline and diesel engines: The meaning of the letters following S or C is: from "SA" to "SN", each increasing letter indicates that the environmental protection level of the oil is better than the previous one. The further back the letter, the higher the environmental protection level. In international brands, most engine oil levels are above SF, and currently, the highest environmental protection level of engine oil is "SN" grade.