Although engine oil is not an original component of a car, it plays a pivotal role in the entire operation process of the car. Engine oil is called lubricating oil. If the engine is compared to the heart of a car, then engine oil is the blood of the car. It not only lubricates the parts of the engine, but also has the functions of cleaning, cooling, rust prevention, and sealing. The engine cannot operate normally at all without the participation of engine oil. This is also to ensure the service life of the engine under high-efficiency operation. So why does the engine oil need to be replaced after the car has traveled a certain distance or after a certain period of time?
As mentioned earlier, engine oil mainly functions as a lubricant in the engine, and also has the functions of cleaning, cooling, rust prevention, sealing, anti-oxidation, buffering, etc. There will also be some loss during the operation of the engine. In addition, as a chemical substance, engine oil has a certain shelf life (especially when the engine is running at high speed and high temperature). After the shelf life, its effect will deteriorate or even fail. Furthermore, engine oil has a cleaning effect on the inside of the engine. Moreover, if some poor-quality engine oil is used, it will damage the auto engine parts and affect the service life of the car.
Generally speaking, regular mineral oil requires maintenance every 5,000 km. In fact, car owners generally do not choose mineral oil (except for the requirements of some owners of low-end cars). Semi-synthetic engine oil can be maintained at 7,500 km. At present, most 4S stores of Japanese cars use semi-synthetic engine oil for maintenance. Fully synthetic engine oil can be used up to 10,000 km, and its anti-oxidation and anti-wear additives are just starting to work at 8,000 km. Therefore, engine oil does not require maintenance and replacement every 5,000 km without exception. For turbocharged models, it is recommended to use fully synthetic engine oil.
When a car undergoes maintenance each time, the correct approach is to clean out the remaining engine oil inside. The purpose of doing this is to avoid oil sedimentation. Develop the habit of regular maintenance. Different cars have different instructions; some manuals specify changing the oil every 5,000 kilometers, others every 7,500 kilometers, and the mileage for the first maintenance is even lower. So when exactly should the oil be changed? In fact, using the car’s mileage is the most common method, but there is also the method based on time. Of course, the frequency of oil changes should be determined according to one’s actual situation.
