Technically, it is difficult to distinguish between the pros and cons of oil, and the test oil standard is nothing more than "look, smell and ask."

The so-called hope refers to the color of the oil, the good oil color is golden and crystal clear, the flow speed is uniform when filling without obvious block or rhythm; If the color is uneven, the abnormal color lines when filling flow may be inferior oil or recycled oil. Smell is judged by the taste, good oil has a slight aroma, poor oil will have pungent odor and even the taste of fuel, this oil base instinct judgment for recycled oil; It's just a rhyming question. Make sure you don't get an answer that says fake oil; After looking at the color and smell of the cut finger, you can touch it and grind it with your fingers. If you feel astringent, poor viscosity, or even have impurities, you can basically judge it as fake oil.

These several simple ways can roughly judge the quality of the oil, as for the brand and level no longer repeated only in the description of the oil label choice:

Take 5W-30 as an example, W stands for winter/low temperature. The number before W plus minus 35 is the freezing point of oil or understood as low temperature fluidity. 5W is minus 30 degrees, and the ideal temperature for practical application is minus 20~25 degrees. 30 represents high temperature fluidity or oil viscosity. The normal working temperature of the engine is about 85~125 degrees. The stronger the high temperature fluidity, the smaller the engine running resistance and the more direct the performance; The larger the number, the higher the viscosity, such as 40 viscosity engine crankshaft stirring oil resistance will increase, power will be significantly worse. The high temperature fluidity/viscosity of selected oil is determined by the recommended value in the manual, and the low temperature fluidity before W is determined by the actual ambient temperature; After the service life of the vehicle is too long and too many kilometers begin to appear slightly burning oil, the viscosity of the selected oil should be properly improved, with the purpose of increasing the viscosity to increase the thickness of the oil film. Although this upgrade reduces the power, it can solve or prevent the phenomenon of slightly burning oil.