| 摘要 |
Provided is a lubricating oil composition that can keep metal-to-metal friction coefficients high and that has excellent seizing resistance. This lubricating oil composition is characterized by comprising, in a lubricating-oil base oil, (A) at least 0.05 mass% of a polysulfide, (B) at least 0.05 mass% of a thiadiazole, and (C) at least 0.1 mass% of a phosphorus-based additive with respect to the total amount of the composition, wherein: the sulfur content in the composition is at least 0.2 mass% in terms of sulfur atoms; the phosphorus content in the composition is at most 0.2 mass% in terms of phosphorus atoms; and the ratio (S/P) of the mass percentage in terms of sulfur atoms to the mass percentage in terms of phosphorus atoms is from 3.0 to 5.0. |
