Before talking about the oil replacement cycle, we need to simply know what the oil is used for. Oil is engine oil, as the name suggests, the most important role is to lubricate the engine and reduce wear.

There are many metal surfaces in the engine that friction with each other, these parts move fast, the environment is "poor", the working temperature is very high, in such "harsh" conditions, the lubrication of oil is particularly important.

The engine is known as the "heart" of the car, and the oil is often compared to the "blood" of the engine.

In addition, the oil also plays a role in sealing the engine to prevent leakage, rust and corrosion, shock buffering, and auxiliary engine cooling and cooling.

There are many classification methods of oil, such as according to the viscosity division, according to the fuel economy grade division, different scenarios, the selection of oil has different requirements.

Common household car oil can be roughly divided into three categories according to its synthesis method, ordinary oil (non-synthetic mineral oil), semi-synthetic oil and fully synthetic oil.

Ordinary oil is the non-synthetic traditional mineral oil, which is a "crude oil" that is simply refined after being mined from the ground, while the full synthetic oil is the oil synthesized in the laboratory, and the semi-synthetic oil is a mixture of the two.

Different types of oil also have different performance, and the type of oil will have a certain impact on engine performance, fuel consumption, and even vehicle emissions.

In general, fully synthetic oil can provide better anti-wear protection and high temperature protection for the engine, followed by semi-synthetic oil, and then ordinary oil.

At the same time, different components also determine the service life of different types of oil.

In the time dimension, the time life of different types of oil is usually not the same.

Relevant studies have shown that the main forms of engine oil quality deterioration are oxidation deterioration and pollution deterioration, and the antioxidant in the oil additive will degrade and fail with the increase of time. Therefore, even if the car is parked for a long time, it needs to change the oil regularly.

Different types of oil, due to different composition, oxidation rate is not the same. In general, conventional mineral oils oxidize faster, and synthetic oils oxidize relatively slowly.

Additives in oil, such as some antioxidants, can also effectively extend the service life of oil.

In terms of mileage, the oil life is also different under different working conditions.

In the operation of the engine, the oil is dynamically involved and plays a role, so the life of the oil is also related to the operating state of the engine.

Simply put, the more the engine spins, the greater the oil consumption will be.

The service life of oil is related to the type of oil, and there are also differences in different models and different working conditions.

How long the oil is changed depends on the type of oil used (fully synthetic oil, semi-synthetic oil, mineral oil), in general, the replacement time of fully synthetic oil is one year or within 10,000 kilometers; Semi-synthetic oil is within 7500 km or 6-8 months; Mineral oils in one or five years. But here, to give you a relatively rough data reference, but also need to be based on the actual situation.