LUBRICANT OIL COMPOSITION

摘要

PROBLEM TO BE SOLVED: To obtain a lubricant oil composition for transmission gears that has excellent increasing effect on both of dynamic and static friction coefficients, particularly of a wet clutch. SOLUTION: The objective lubricant composition is obtained characteristically by formulating (A)>=0.035 mass % of a boron-containing, ash-free dispersant calculated as boron on the basis of the whole amount of the composition and (B)>=0.01 mass % of an alkaline earth metal sulfonate with the whole base value of 50-500 mg KOH/g calculated as an alkaline earth metal on the basis of whole amount of the composition, to a lubricant base oil.