| abstract |
A gear oil composition excellent in flame retardancy and self-extinguishing properties is provided. A gear oil composition, wherein (A) a phosphorus-containing compound having a kinematic viscosity at 40 ° C. of 1 to 1,000 mm 2 / s as a base oil is 20 to 70% by mass with respect to the total amount of the base oil, and (B) One or more selected from a polyol ester and a complex ester having a kinematic viscosity at 40 ° C. of 100 to 30,000 mm 2 / s and a flash point of 200 ° C. or higher is 30 to 30% based on the total amount of the base oil. 80% by mass, (C) tetrazole, 0.5 to 5.0% by mass with respect to the total amount of the gear oil composition, and (D) extreme pressure agent containing sulfur, the gear oil composition A gear oil composition containing 0.1 to 10% by mass with respect to the total amount and having a kinematic viscosity at 40 ° C. of 50 to 1,000 mm 2 / s. [Selection figure] None |