What does 5w30 engine oil mean?
2 Answers
5w30 is the viscosity specification of engine oil grade. The viscosity specification of engine oil grade is divided into three parts: w, the number before w, and the number after w. w stands for winter; The number 5 before W indicates that the applicable temperature is minus 3 degrees. The smaller the number, the greater the viscosity of the engine oil at low temperatures; The number 30 after w refers to the kinematic viscosity at 100 degrees Celsius. The larger the number, the higher the viscosity of the engine oil and the stronger the ability to withstand high temperatures. Engine oil, also known as engine lubricant, plays roles such as lubrication and wear reduction, auxiliary cooling, sealing and leakage prevention, rust and corrosion prevention, shock absorption, and buffering for the engine.
That day I happened to be at the repair shop watching the mechanic change the oil. He told me that 5W30 is a standard oil viscosity rating. The 5W represents the oil's low-temperature performance in winter, meaning it can still flow smoothly at -25°C to aid cold starts. The 30 indicates the oil's high-temperature viscosity in summer, maintaining stable protection against engine wear under heat. After driving for so long myself, I've realized how crucial viscosity ratings are - using the wrong one increases engine noise and fuel consumption, especially making winter starts difficult, so it's worth double-checking. Manufacturers recommend 5W30 because it suits most climates, but if you live in extreme cold or heat, some adjustment may be needed. Never neglect regular oil changes - the engine's lifespan depends on it. A simple oil change can save you from major repairs, and I always notice smoother acceleration and better fuel efficiency after each change.
