What Is Motor Oil Viscosity?
Motor oil is the lifeblood of any engine. It keeps all the moving parts from grinding against each other and causing irreparable damage. When you buy motor oil for a car, you might notice a variety of viscosity ratings like 0W-20 or 10W-40. What does that mean?
One of the difficulties with motor oil is the wide temperature range engines start and operate at. In cold weather, motor oil needs to be thin enough to allow the engine to start. At high operating temperatures, the oil needs to be thick enough to provide lubrication. The two numbers in viscosity ratings…