| abstract |
This invention relates to a lubricating composition comprising a major amount of an oil of lubricating viscosity and (A) a di or trihydrocarbyl phosphite, (B) at least one reaction product of a di or trihydrocarbyl phosphite and sulfur or a source of sulfur; at least one di or trihydrocarbyl monothiophosphate; or salt thereof, and (C) a salt of a hydrocarbyl phosphoric acid ester. In one embodiment, the lubricant composition contains less than 0.1% phosphorus or less than about 0.75% borated dispersant. This combination of phosphorus compounds provides antiwear and thermal stability to lubricants, even at low phosphorus levels. The lubricating compositions containing the combination of the phosphorus compounds has low corrosivity to copper and low odor as well. |