METHOD FOR IMPROVING NITRILE SEAL COMPATIBILITY WITH LUBRICATING OILS

摘要

Provided are a lubricating engine oil and a method of improving nitrile seal compatibility with a lubricating oil in an engine lubricated with such lubricating oil. The method includes using as the lubricating oil a formulated oil comprising a lubricating oil base stock as a major component and one or more additives selected from the group consisting of (i) a sulfone, sulfolane, or derivative thereof; (ii) a borate ester, boron amide, or mixtures thereof; (iii) a sulfurized olefin; (iv) a thiadiazole or derivative thereof; and (v) a succinic anhydride or derivative thereof, as a minor component. Nitrile seal compatibility is improved as compared to nitrile seal compatibility achieved using a lubricating oil containing a minor component other than the one or more additives.