we stored motor oil in 55-gallon ... Viscosity is an oil's ability to flow at different temperatures. Multi-weight oils like SAE 5W-30 (the "W" stands for winter weight) perform well over wide ...

In the past, there have been similar shifts in preferred engine oil viscosity grades. An example is the transition in heavy duty diesel engine oils in the 1980s from monograde viscosity SAE 30 and ...