LUBRICATING OIL COMPOSITION FOR INTERNAL COMBUSTION ENGINE

摘要

A lubricating oil composition for internal combustion engines which is excellent in antiwear performance and high-temperature detergency although reduced in ash content and is especially suitable for use in diesel engines equipped with an exhaust-gas post-treatment device. The lubricating oil composition for internal combustion engines comprises a base oil comprising a mineral oil and/or a synthetic oil and, incorpoarted therein, A 0.08 to 0.40 wt.% ash-free succinimide dispersant in terms of nitrogen amount, B 0.06 to 0.22 wt.% metallic detergent in terms of metal element amount, C 0.04 to 0.08 wt.% zinc sec-alkyldithiophosphate in terms of phosphorus amount, and D 0.01 to 0.04 wt.% ash-free phosphorus-compound antiwear agent in terms of phosphorus amount. The content of sulfated ashes derived from metal elements in the composition is 0.3 to 1.0 wt.%.