What is the classification of diesel engine oil?
2 Answers
Diesel engine oil grades are roughly divided into: CA, CB, CC, CD, CE, CF, CF4, CG4, CH4, CI4, CJ4. Here is more information about diesel engine oil grades: 1. Different models of diesel engine oil indicate different oil grades and corresponding applicable vehicle models. In other words, the further back the letters are arranged, the higher the oil quality grade. 2. The English letter C at the beginning represents diesel engine oil. The further back the letters are arranged, the higher the oil quality grade. Generally, CD-grade oil is sufficient for ordinary diesel engines. Turbocharged diesel engines require higher oil quality, such as CF4, where 4 indicates that the oil is suitable for four-stroke diesel engines.
I've worked on many diesel vehicles, and the classification of engine oil mainly depends on the API standards, which are a set of rules established by the American Petroleum Institute. Diesel engine oil grades start with 'C,' such as CH-4, CI-4, CJ-4, CK-4, and FA-4. These represent the level of engine protection, with higher numbers indicating newer standards. For example, CK-4 is the mainstream standard post-2016, suitable for modern engines with exhaust gas recirculation. Viscosity is also crucial, like 5W-30 or 15W-40, where the first number indicates low-temperature fluidity and the second denotes high-temperature protection. Choosing engine oil isn't just about the grade; you also need to refer to the vehicle's manual, as different engines have specific requirements. Older heavy-duty trucks might only need CI-4, while newer cars may require CK-4 or higher to reduce emissions and maintenance costs. Don’t randomly select the grade—using the wrong one can accelerate wear or clog the DPF system. It's recommended to check the label during regular oil changes.
