What are the classifications and specifications of engine oil grades?
2 Answers
Engine oil grades generally include SA, SB, SC, etc., with SN being the highest grade. Common specifications include 5W30, 5W40, 0W30, 0W40, etc. Below is a related introduction to engine oil specifications: 1. Selection of engine oil types for vehicles: There are two parts. 2. Winter engine oil: There are 6 types, namely 0W, 5W, 10W, 15W, 20W, 25W. 'W' stands for Winter, and the smaller the number before it, the better the oil's fluidity and the lower the applicable temperature. 3. Summer engine oil: There are 5 types, namely 20, 30, 40, 50, 60. The larger the number, the higher the oil's viscosity and the better its high-temperature protection performance, making it suitable for higher temperature environments. 4. All-season (winter and summer) engine oil: There are 16 types, namely 5W20, 5W30, 5W40, 5W50, 10W20, 10W30, 10W40, 10W50, 15W30, 15W40, 15W50, 20W20, 20W30, 20W40, 20W50. 5. Selection of viscosity grade: Many factors influence this, such as driving environment, driving habits, vehicle model, etc. Different vehicle models have different actual working conditions, and thus require different viscosity grades. For example, German cars are recommended to use higher viscosity oil, while Japanese and Korean cars are the opposite, using lower viscosity oil, which is due to differences in engine internal structure.
There's actually quite a variety of motor oil grades and specifications. Having driven for over a decade and frequently helped friends choose oil, I've found two main factors matter most: First is viscosity grade - SAE labels like 5W-30 or 10W-40 indicate lower numbers mean easier cold starts (better for winter). Second is API rating such as SP or SN - higher letters mean cleaner oil that reduces engine carbon buildup. My experience shows it's best to follow your vehicle manual's recommendation - Toyotas typically use 0W-20 synthetic while Volkswagens often require 5W-30. Using the wrong oil can significantly increase fuel consumption. Also, when buying branded oils like Mobil or Shell, always verify specifications on the bottle and avoid counterfeit products. I once used incorrect oil which caused loud engine noise, requiring urgent shop attention to prevent major damage. Remember to check oil condition every 5,000 km to prevent aging damage to your engine.
