Marine diesel engine lubricating oil composition having improved high temperature performance

摘要

A lubricating oil composition containing a base oil of lubricating viscosity, overbased sulfurized alkylphenate detergent or its calcium salt, an overbased alkylsulfonate detergent or its calcium salt, an ashless dispersant, and a zinc dialkyldithiophosphate and/or zinc diaryidithiophosphate is described. The lubricating oil composition provides improved heat stability and anti-wear performance in marine diesel engines operated under severe conditions where the cylinder liner temperature may reach 200 to 260° C.