What does the oil grade mean?
2 Answers
The oil grade indicates viscosity and quality. The oil grade consists of two parts: classification and viscosity specification. The number following the classification represents its viscosity specification, which is divided into high-temperature types for summer use, low-temperature types for winter use, and all-season types for year-round use. Engine oil, or engine lubricant, is a substance enhanced with additives in base oil, primarily containing anti-wear additives, detergents, dispersants, and multi-grade viscosity index improvers. The main functions of engine oil are to reduce friction and wear of moving parts, and to remove sludge (one of the functions of dispersants) and varnish (the function of detergents) from the engine.
As a veteran driver who frequently takes long trips, the motor oil grade is the combination of numbers and letters on the packaging, such as symbols like 5W-30. Simply put, it represents the viscosity grade of the oil. The 'W' stands for winter, and the smaller number before it indicates better oil flow at low temperatures during startup, preventing it from being too thick. The larger number after it means the oil can protect the engine at high temperatures. Choosing the wrong grade can accelerate engine wear. For example, when I drive more on mountain roads, I use 10W-40, which works well in both winter and summer. Otherwise, the engine starts slowly in cold weather. When changing the oil, always check the standards recommended in the car manual—don’t just rely on the mechanic’s advice to avoid wasting money and damaging the engine. Regular checks and oil changes can extend the car’s lifespan, after all, the engine is the heart of the car.
