Patent ID: 8258087

Claim:
A lubricating oil composition for internal combustion engine, which comprises: (A1) a lubricant base oil as a main component characterized by kinematic viscosity at 100 degree C. being 1 to 8 mm 2 /s, aniline point being 100 degree C. or more, paraffinic content in saturates being between about 40% and 70 mass %, monocyclic naphthenic content in saturates being 25 mass % or less, bicyclic to hexacyclic naphthenic content in saturates being 35 mass % or less, iodine number being 2 or less, and ratio of tertiary carbon to the total carbon atoms composing the (A1) being 6.3% or more; and which further comprises, to the total mass of the composition: (B) 0.16 to 0.5 mass % of a metallic detergent as metal content; (C1) 0.005 to 0.2 mass % of a boron-containing succinimide ashless dispersant as boron content.