SAE Gradation (Society of Automotive Engineers)

The importance of viscosity is that much which society of automotive engineering of the USA with acronym of SAE, has put in place a special gradation system for classifying engine lubricants according to their viscosities, and recognizes SAE grade as one of two selection standards of engine oil. This procedure is acceptable to all engine oil producers and consumers worldwide.

Oils are divided into two main groups based on viscosity: Mono grade oils as Ecco V HD 50, and Multi grade oils as Ecco V Prima 10W40, Ecco V Dinol 15W40 and Ecco V 16000 20W50. Multi grade oils are specified with “W” letter (means winter) and two numbers in its left and right sides. Multi grade oils are appropriate to use in all seasons of year functionally. The left side number of W, refers to the low-temperature viscosity and the right side number refers to the high-temperature viscosity (summer).

It is proved that the most important property of oil is its presence on all the moving and fixed parts of engine from the start moment till its switch off nonstop, and for achieving this goal, low-viscosity of oil at engine start moment is very important. For this reason, using of multi grade oils which have low viscosity in cold air and with timely lubricating of components, prevent engine parts wear is the first recommendation of oil producers.