How much oil is left for maintenance?
3 Answers
Engine oil is not replaced based on how much is left, but rather on the mileage driven. Mineral oil is recommended to be changed every 5,000 km, while fully synthetic oil can be changed every 10,000 km or even more. The physical and chemical properties of engine oil are very stable, with a shelf life of 4 to 5 years. If the car is driven less frequently, it is recommended to change the oil every six months. The main functions of engine oil are to reduce friction and wear on moving parts and to remove sludge and paint from the engine. The method to test whether the oil needs to be changed is to drop a drop of oil onto a slow qualitative test paper and observe the color change of the oil, which generally takes 24 hours.
I usually change the engine oil based on mileage, typically needing maintenance every 5,000 to 10,000 kilometers. However, the actual condition of the oil also matters. Like during my last service, the mechanic taught me to use the dipstick to measure—if the level is below the 'min' line, it's time for a change. The easiest way is to check regularly, like asking the mechanic to inspect the oil color during car washes. If it turns black or thickens, it's a sign to replace it. My neighbor, Old Zhang, is very particular about his car. He says aggressive driving can cut the oil's lifespan in half, so he checks it extra after every highway trip. Remember, the first service for a new car is crucial—the dealership recommends an oil change at just 3,000 kilometers.
My car has an oil life monitoring system, and the dashboard displays the remaining percentage. It usually reminds me to get maintenance when it drops below 20%. However, the most accurate method is still checking the dipstick. I prefer to measure it when the engine is cold—pull it out, wipe it clean, reinsert it, and then check. The ideal oil level is about two-thirds between the upper and lower marks. If I notice metal particles in the oil or a burnt smell, I change it immediately, even if the mileage hasn't been reached. Last time, the mechanic at the service shop mentioned that full synthetic oil lasts longer and can go up to 10,000 kilometers, while mineral oil should be changed every 5,000 kilometers.
