| abstract |
Provided is a lubricating oil composition having good cleanliness despite low sulfated ash content and having a good friction reducing action even after deterioration. A lubricating oil composition comprising a base oil (A), a metal-free sulfur-based antioxidant (B), and a hindered amine having one piperidine-derived skeleton in the molecule. A sulfur content of the metal-free sulfur-based antioxidant (B) is 800 mass ppm or more based on the total amount of the lubricating oil composition. The content of the hindered amine antioxidant (C) in terms of nitrogen atom is 100 mass ppm or more and 400 mass ppm or less based on the total amount of the lubricating oil composition, and the sulfated ash content of the lubricating oil composition is 0.70 mass. %, And the lubricating oil composition has a total base number of 4.0 mgKOH / g or more. [Selection figure] None |