Lubricating oil compositions with improved performance

Abstract

Disclosed are stabilized lubricating oil compositions with improved oxidative performance. These lubricating oil compositions contain certain phenolic antioxidants, in combination with other antioxidants, which contribute to the improved performance. These certain phenolic antioxidants are defined in formula (I), wherein, R1 is alkyl of 1 to 4 carbon atoms, n is 1 to 4, R2 is H or R3, R3 is —(CH2)x—COOR4 where x is 1 to 10, R4 is straight or branched chain alkyl of 1 to 24 carbon atoms or E, when n is 1, E is straight or branched chain alkyl of 1 to 24 carbon atoms; when n is 2, E is straight or branched chain alkylene of 2 to 12 carbon atoms or said alkylene interrupted by one to five O or S atoms; when n is 3, E is a straight or branched chain alkanetriyl of 3 to 6 carbon atoms; and when n is 4, E is pentaerthyrityl.

Dependencies are inferred from the claim text.