The present invention provides a low ash engine oil composition which, despite the low ash content, has engine detergency which enables the composition to pass severe detergency tests for diesel engine oils. The engine oil composition contains 0.6 percent by mass or less of a sulfated ash and comprises a low ash engine oil composition with a sulfated ash content of 0.6 percent by mass or less, which comprises: a lubricating base oil with a %CA of 2 or less, a kinematic viscosity at 40°C of 25 mm2/s or less and a viscosity index of 120 or greater; a viscosity index improver contained in such an amount that the viscosity index of the composition will be 160 or greater; (A) a metallic detergent with a metal ratio of 3 or less; and/or (B) a sulfur-free phosphorus compound.
本发明提供了一种低灰分发动机油组合物,尽管灰分含量低,但其发动机清净性却能使该组合物通过柴油发动机油的严酷清净性测试。该发动机油组合物含有 0.6% 或更低质量的
硫酸盐灰分,包括
硫酸盐灰分含量为 0.6% (以质量计)或更低的低灰份发动机油组合物,其中包括:润滑基础油,其 %CA 为 2 或更低,40°C 时的运动粘度为 25 mm2/s 或更低,粘度指数为 120 或更高;粘度指数改进剂,其含量应使组合物的粘度指数为 160 或更高;(A)
金属比为 3 或更低的
金属清净剂;和/或 (B) 无
硫磷化合物。