| abstract |
PROBLEM TO BE SOLVED: To improve the high temperature cleanliness of a piston portion despite the fact that it contains an ultra-low ash content of a level substantially free of ash content derived from a metal detergent, which could not be achieved only by optimizing the conventional additive composition. An excellent lubricating oil for an internal combustion engine is provided. The heavy fraction of GCD at 550 ° C. or more is 6% by volume or more, the sulfated ash content is 0.6% by mass or less, and the content of the additive containing a boron compound is at least 0. A lubricating oil composition for an internal combustion engine, characterized by being 02 mass%. [Selection figure] None |