Patent ID: 8592355

Claim:
An engine oil composition, consisting essentially of: (A) a base oil mixture comprising a first base oil and a second base oil, the first base oil having a kinematic viscosity of 2 to 50 mm 2 /s at 100° C., a viscosity index of 80 or higher, and a sulfur content of less than 0.03 mass %, the second base oil having a kinematic viscosity of 2 to 50 mm 2 /s at 100° C., a viscosity index of 60 or higher, and a sulfur content of 0.03 mass % or more; (B) an oil-soluble molybdenum-containing composition which is prepared by reacting an acid molybdenum compound or a salt thereof with succinimide at a temperature of of 120° C. or lower to form a product (m); and subjecting product (m) to a stripping process, a sulfurizing process, or a combination of these at a temperature of 120° C. or lower to produce an oil-soluble molybdenum-containing composition having a light absorbance of less than 0.7 at a wavelength of 350 nm; and (C) a molybdenum-based friction modifier, wherein based on the total amount of engine oil composition, the content of the second base oil is 1 to 15 mass %, the content of (B) oil-soluble molybdenum-containing composition is 50 to 1000 mass ppm in terms of amount of molybdenum, and the content of (C) molybdenum-based friction modifier is 100 to 1000 mass ppm in terms of amount of molybdenum.