How Important Is Viscosity in Engine Oil?

Answer Viscosity or kinematic viscosity--the resistance of a liquid to flow--is one of the most important characteristics of engine oil. The viscosity of engine oil must be sufficient to lubricate the mov... Read More »

Top Q&A For: How Important Is Viscosity in Engine Oil

How to Rate Engine Oil Viscosity?

Engine oil contains a base oil and additives that help with its performance. Engine oil is rated based on its viscosity. Viscosity is a measure of how easily the oil flows. A "W" next to the viscos... Read More »

How to Cut Oil Viscosity?

Every bottle of oil has a viscosity rating. For example, 10W30 oil has a viscosity of 10 when cold and a viscosity of 30 when heated up. The higher each number, the thicker the oil. Many people mix... Read More »

What Is Oil Viscosity?

Oil is rated by the Society of Automotive Engineers (SAE) for viscosity. Viscosity is a rating which describes the thickness of a fluid. Engines are designed to use oil rated at a certain viscosity... Read More »

Viscosity of Used Oil vs. New Oil?

Many drivers know they must periodically change their vehicle's oil, but some car owners may not understand why the oil does not last forever. As the vehicle runs, the oil's viscosity changes and t... Read More »