How Many Kilometers Should You Change Your Engine Oil?
3 Answers
For the timing of engine oil changes, it is generally recommended to follow the vehicle's user manual, which suggests changing the oil every 5,000 kilometers or every 6 months, whichever comes first. Types of Engine Oil: Engine oil can be divided into three types: full synthetic oil, semi-synthetic oil, and mineral oil. Engine Oil Specifications: The packaging of engine oil often displays specifications such as 5w30, 0w20, or 5w40, which indicate the oil's type. The 'w' stands for 'winter,' meaning that if the oil has the letter 'w,' it can be used during winter. Precautions for Oil Change: When the viscosity of the engine oil changes significantly under high temperatures, it is generally considered necessary to replace the oil if the kinematic viscosity at 100 degrees Celsius deviates by more than 20%. Additionally, if the oil's detergency and dispersancy performance decline, it may no longer effectively dissolve and disperse the carbon deposits produced during engine operation.
I was also really torn about this when I first bought my car. In fact, there's no one-size-fits-all answer—it depends on the specific vehicle condition and oil type. My old naturally aspirated car uses mineral oil, and the mechanic insists I change it every 5,000 km to protect the engine. But my colleague’s new car uses full synthetic oil, and the dealership says it’s perfectly fine to go 10,000 km. The most reliable method is to check your car’s maintenance manual; the manufacturer’s test data is far more accurate than online rumors. Cars with lots of short commutes experience faster oil degradation, while frequent highway driving can actually extend the interval. In northern winters, cold starts are tough on the engine, so I change the oil a few hundred kilometers early. Remember to have the mechanic check the dipstick during each service—if the oil is black or has lost viscosity, it’s time for a change.
It depends on how you use your car. I drive for Didi and am always stuck in city traffic, with the engine constantly running at low RPMs, leading to severe carbon buildup. The mechanic suggested that under such conditions, I should change the oil every 7,000 km, otherwise sludge will clog the oil passages. A friend who enjoys weekend road trips can go up to 12,000 km with the same oil. There's also the quality difference in oils—full synthetic oil resists degradation more than twice as well as mineral oil. German cars, with their higher oil temperatures, demand even stricter oil quality. Don't believe the nonsense online about 'changing oil only at 15,000 km.' Once I tried changing at 10,000 km, and the engine sounded like a tractor. Regularly checking the oil condition is the most practical approach.
