Operation method
As shown in the figure, we can see the string identification of API SN/CF SAE 5W/40 from the lower left corner of the bottle body. First, we will take the string apart.
The first line: API SN/CFAPI: API (American Petroleum Institute) is the abbreviation of American Petroleum Institute. API grade represents the quality grade of engine oil. It uses simple codes to describe the working ability of the engine oil. SN: S series represents gasoline engine oil, and N represents grade. Specifications: API SA, SB, SC, SD, SE, SF, SG, SH, SJ, SL,SM, SN。 The higher the letter from SA to SN, the higher the quality. There will be more additives used to protect the engine in the oil. CF: "C" series represents diesel engine oil, and F represents grade. Specifications: API CA, CB, CC, CD, CE, CF, CF-2, CF-4,CG-4, CH-4, CI-4, The higher the letter after the same is, the higher the quality is. The NX9 engine oil has both SN and CF marks, which means that the product has the performance of SN grade of gasoline engine oil and CF grade of diesel engine. The second line: SAE 5W/40SAE: The Society of Automotive Engineers (SAE) classifies the engine oil according to the oil viscosity classification method, and classifies the lubricating oil into high-temperature type Low temperature type for winter and all-weather type for winter and summer. 5W: The symbol W stands for winter. The smaller the number before W, the smaller its low-temperature viscosity, the better its low-temperature fluidity, and the lower the applicable minimum temperature; Usually: 0W, 5W, 10W, 15W, 20W, 25W. Owners in North China can choose 0W, and those in South China can choose 5W. 40: It represents high temperature performance. The larger the number, the greater the viscosity, and the higher the applicable maximum temperature; Usually: 20, 30, 40, 50. The general oil grades in winter and summer are respectively 5W ／ 20, 5W ／ 30, 5W ／ 40, 5W ／ 50, 10W ／ 20, 10W ／ 30, 10W ／ 40
It can be seen from the above that the quality of engine oil does not depend only on the brand. The meaning of the engine oil label is more important than the brand. I hope that the majority of car owners can buy the most suitable engine oil.
