What is the different between 15w – 40 and 10w-40 meant in the diesel engine oil?
The winter viscosity rating is lower (the 10W) in the 10W-40. If you are in a cold climate use the 10W-40. engine oil Engine oil grades As long ago as 1911 the Society of Automotive Engineers recognized a need for standardizing grades of oil for automobile engines. Today the ratings are provided in collaboration with the ASTM and the American Petroleum Institute (API). In the United States, engine oil ratings are indicated by a trademarked circular design on the package. The mark contains three pieces of information. In the inner circle is a viscosity grade. In the upper part of the outer circle is an API Service Classification, and the bottom of the outer circle may contain an energy conservation rating. The package may also have a starburst symbol. The presence of this symbol indicates that the oil meets standards set by the International Lubricant Standardization and Approval Committee, whose members represent American and Japanese automobile manufacturers. Viscosity The purpose of
