The changing of the viscosity with temperature is determined by the viscosity index (VI). We know that the viscosity and temperature are inversely proportional and we need to take care about high viscosity because of the losses which take place due the churning and squezzing. The higher the viscosity of the lubricating the thicker the film and this improve the properties against wear, damping and scuffing loading capacity. One important property of the gear oil is the viscosity and it has direct influence in the formation of the lubricant film. The lubricant is used in a gearing system mainly to control friction and wear between metal surfaces and to transfer heat away from the contact área. The purpose of this article is to provide some basic information about gear oil viscosity which can help engineers to specify the right gear oil.
