Can oil be mixed? Will it affect the engine?

The most important step in car maintenance is to change the oil. However, in addition to the normal oil change, if the oil is lost and new oil needs to be added, many car owners think that as long as the oil level and viscosity are the same, it will not affect the use of other brands of oil at all. However, the fact Is this really the case?

Different oils cannot be mixed.

At present, there are many kinds of engine oil on the market, various viscosities, various models, and various choices. Faced with rows of engine oil shelves, many car owners do not understand engine oil knowledge and often fall into the misunderstanding of engine oil use. For example, the problem of mixed oil. Many car owners will choose different oil brands when maintaining their cars, because they believe that as long as the type and level of oil are the same, there is not much difference between the oils, and the mixing is completely fine.

However, engine oil is composed of base oil and additives. Although additives account for a relatively small proportion, they determine the performance of engine oil. The additive formula of each engine oil is also different. If mixed at will, it is likely to cause chemical reactions between additives, reduce lubrication effect, precipitate stratification, and reduce cleaning performance, resulting in engine oil failure.

Old and new oil can not be mixed

All car owners must pay attention to the fact that old and new oils cannot be mixed. The answer is very simple. It is like a bottle of beverage that has been opened for a long time and has almost deteriorated. Mix it with a bottle of newly opened beverage. Regardless of the brand and model, the mixed beverage is not suitable for drinking again. In the same way, the old engine oil contains a lot of oxidizing substances. When the new engine oil is mixed with the old engine oil, the new engine oil will be polluted and the oxidation deterioration rate will be greatly accelerated. Even if the performance will not decline significantly, compared with the new engine oil, The service life is still greatly shortened. Therefore, when changing the oil, we must pay attention to the fact that the old oil should be put clean and not have too much residue.