Gear oil is dark in color and heavy in smell, is it a quality problem?

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Gear oil is dark in color and heavy in smell, is it a quality problem?

Engine gear oil is a higher viscosity lubricant, designed to protect the transmission of power parts, in the contact surface between the teeth and teeth, can form a continuous tough oil film, that is, with a high degree of oily, so that the transmission of oil between the transmission parts to maintain the toughness of the boundary oil layer, to ensure that the transmission parts wear and tear is small and to prevent it from abrasion.

We know that the composition of the lubricating oil for the basic oil and additives, vehicle gear oil is no exception, so what kind of base oil and additives used to determine the color and smell of vehicle gear oil.

For large vehicles commonly used in heavy-duty gear oils, due to heavy loads and extreme pressure requirements, in general, the base oil are used in the base oil of a larger part of the viscosity of a better bearing capacity of a class of base oils, and a class of base oils due to the origin and production process of different colors ranging from transparent to dark brownish-red, the smell is also different (the color of the base oil and the smell of the base oil can not be characterized base oil quality is good or bad).

Now on the market, the color of gear oil for large vehicles is also divided into two main categories, dark yellow or dark brown-red, which is in addition to the base oil has a relationship with the selection of additives also has a great deal to do with the market several well-known additive composite agent company's additive system have their own characteristics, and even with the same composite agent company, the composite agent of the gear oil will also be subdivided into several categories. This also leads to the market vehicle gear oil color and smell more diversified.

Some garage masters like to judge the gear oil according to the color and smell to the good or bad, said the smell of gear oil quality is not good, because it may be used in the recycling of pickling oil or poor quality oils, this statement is not true, the smell is part of the characteristics of a class of base oils, and at the same time, due to the existing gear oil additives mainstream use of extreme pressure sulfur and phosphorus type of compounding agent system, but also lead to the smell of the vehicle gear oil with a part of the sulfur It also leads to the odor of vehicle gear oil with part of sulfur's irritating odor. Conclusion: So the smell and color can not be used to directly judge the gear oil good or bad.