What is the classification of automotive engine oil grades?
1 Answers
Automotive engine oil grades range from SA up to SN, with each successive letter indicating improved performance over the previous grade. The further the letter is in the alphabet, the higher the quality grade. The functions of engine oil are: 1. To separate the surfaces of relatively sliding parts, thereby reducing wear; 2. To carry heat back to the oil tank and then dissipate it into the air, assisting the radiator in cooling the engine; 3. To circulate carbon deposits, sludge, and worn metal particles from engine parts back to the oil tank, flushing away contaminants generated on the working surfaces of parts through the flow of the lubricating oil. The effects of using inferior quality engine oil are: gum and incompletely combusted substances can accumulate on valves, intake passages, and combustion chambers, affecting engine operation and potentially causing engine damage.