What is SAE Classification for Lubricants?
SAE (Society of Automotive Engineers) viscosity classification is the most widely used system to classify Engine Oil viscosity. The system, has been adopted worldwide for engine oil viscosities. Two series of SAE viscosity are defined: those with the suffix “W”, which are essentially for winter conditions and those without the “W”. For the W grades, viscosity is measured by two test methods, one in the cold cranking simulator and the other in a pumping test that evaluates borderline pumping temperature. The cold cranking simulator reports dynamic viscosity in Pascal seconds (Pa s), but the W grades have additionally to meet minimum viscosity requirements at 100C measured in mm2/s. For the grades without the W, viscosity is defined in mm2/s at 100C and there is no requirement for the tests applied to the W grades.
