Patent ID: 8309499

Claim:
A lubricating oil composition comprising: a base oil having a kinematic viscosity at 100° C. of 2 to 30 mm 2 /s, a % CA, as determined by ring analysis, of 3.0 or less, a sulfur content of 50 ppm by mass or less, and a viscosity index of 70 or more; (A) at least one compound selected from the group consisting of disulfide compounds represented by formula (I): R 1 OOC-A 1 -S—S-A 2 -COOR 2 (I) wherein R 1 and R 2 each independently represent a C 1 to C 30 hydrocarbyl group, A 1 and A 2 each independently represent a group of the formula CR 3 R 4 or CR 3 R 4 —CR 5 R 6 where R 3 to R 6 each independently represent a hydrogen atom, wherein the content of component (A) is determined so that the lubricating oil composition has a sulfur content of 0.3% by mass or less, (B) a molybdenum-amine complex, wherein the content of component (B) is determined so that the lubricating oil composition has a molybdenum content of 50 to 2,000 ppm; and (C) 0.05% to 3.0% by mass based on the total mass of the lubricating oil composition of at least one of a phenol-based antioxidant and an amine-based antioxidant, wherein the lubricating oil composition has a phosphorus content of 0.1% by mass or less, and a sulfated ash content of 1.0% by mass or less.