Gear lubricating oil composition

摘要

A gear lubricating oil composition comprising a base oil of lubricating viscosity having dissolved or dispersed therein an alkali metal borate or a hydrate thereof in an amount of 0.04 to 1.0 wt % in terms of boron content, an oil-soluble sulfur-containing extreme pressure agent in an amount of 0.01 to 5.0 wt % in terms of sulfur content, an oil-soluble phosphorus-containing extreme pressure agent in an amount of 0.001 to 1.0 wt % in terms of phosphorus content, and a zinc dialkyldithiophosphate in an amount of 0.01 to 1.0 wt % in terms of phosphorus content.