an oil meeting the requirements of more than one SAE viscosity grade classification, and may therefore be suitable for use over a wider temperature range than a single-grade oil.
one of the multiviscosity number oils in which one oil combines three SAE viscosity number grades. For example, multigrade SAE 1 OW-40 grade may be used where SAE 1 OW, SAE 20W, SAE 20, SAE 30, or SAE 40 grades are specified. These oils are made possible by improved refining processes and the use of polymer additives.