LUBRICATING OIL HAVING ENHANCED RESISTANCE TO OXIDATION, NITRATION AND VISCOSITY INCREASE

摘要

This invention is directed to an antioxidant system for use in lubricating oils comprising sulfurized isobutylene and hindered phenols that provides enhanced oxidation resistance and is particularly useful in natural gas fueled engines, the method for making this antioxidant system, lubricating oils comprising the antioxidant system and methods for lubricating engines using lubricating oil comprising this antioxidant system.