Patent ID: 8278255
Filing Date: 2012-10-02
Classification: C10M,C10N

Abstract:
1. A lubricating oil with favorable shear stability, consisting of: a) 91.85 to 94.35 wt. % of Group III base stock; b) a viscosity index improver at 4.5 to 7.0 wt. % of the lubricating oil consisting essentially of a polymethacrylate with a permanent shear stability index of less than 20 defined by ASTM 5621 with 10 percent polymer in a Group I mineral oil; c) an antioxidant additive; d) a corrosion additive; and e) at least one additional additive selected from the group consisting of an antiwear additive, metal passivator, demulsifier, pour point depressant, and any combination thereof, wherein the combination of the antioxidant additive, corrosion additive, and at least one additional additive constitutes the balance of the lubricating oil, wherein the lubricating oil has a kinematic viscosity at 40° C. of at least 43.92 cSt and less than 75 cSt, wherein the ratio of the % viscosity loss in KRL of the lubricating oil relative to the same lubricating oil except for a Group I basestock replacing the Group III basestock in the formulation is about 0.7.