| abstract |
A lubricant oil composition having a synergistic oxidative stability is disclosed, the composition comprising at least one hindered phenolic antioxidant, at least one mono-boronated hindered phenolic antioxidant, at least one di-boronated hindered phenolic antioxidant, at least one alkylated diphenylamine and at least one organomolybdenum compound. The invention also provides a lubricating oil additive concentrate composition that imparts synergistic oxidative stability to a lubricant oil upon its addition, the concentrate composition comprising at least one hindered phenolic antioxidant, at least one mono-boronated hindered phenolic antioxidant, at least one di-boronated hindered phenolic antioxidant, at least one alkylated diphenylamine and at least one organomolybdenum compound. Further, the concentrate compositions of the present invention may also be prepared with a high concentration of hindered phenolic antioxidants without deleterious effects on viscosity or lubricant solubility. |