What grade is CK engine oil?

[McMila]

CK belongs to the fourth-grade engine oil. The information about CK fourth-grade engine oil is as follows: 1. Grade standard: According to the diesel engine oil standard established by the American Petroleum Institute (API), the grades from low to high are CC, CD, CE, CF, CF-4, CG-4, CH-4, CI-4, CJ-4. 2. Grade: Each increment in the letter indicates a higher quality grade of the engine oil. Information about engine oil is as follows: 1. Engine oil: (Engine-oil) is the lubricating oil used by the engine. It consists of base oil and additives. 2. Function: The density of engine oil is about 0.91×10³ (kg/m³). It can lubricate and reduce wear, assist in cooling and temperature reduction, seal and prevent leaks, prevent rust and corrosion, and provide shock absorption for the engine. It is known as the 'blood' of the car.