Overview
GL-4 Grade is a gear oil range under API GL-4. Grades: GL4 75W80, GL4 85W90, GL4 85W140. API 1560 describes GL-4 as intended for axles with spiral-bevel gears under moderate to severe conditions, or hypoid gears under moderate conditions; it is also used in some manual transmissions and transaxles.
Every grade has its own row in the specification table, with viscosity at 100 °C, viscosity index, flash point, pour point and density.

