Lubricating compositions

A multigrade lubricating composition comprising at least about 30% by weight of at least one mineral oil having a kinematic viscosity of less than about 8cSt at 100° C., and an amount of a concentrate, sufficient to deliver to the multigrade lubricating composition, (A) from about 15% to about 40% by weight of at least one polymer having a {overscore (M)}w from about 1000 to about 45,000, the polymer being selected from polyalkylenes, terpolymers of ethylene, propylene and a diene monomer, and mixtures thereof, and (B) up to about 30% by weight of at least one fluidizing agent, provided that when the fluidizing agent is a polyα-olefin having a kinematic viscosity from about 2 to about 30 cSt at 100° C., then the poylα-olefin is present in an amount up to about 12% by weight, wherein the lubricating composition is a gear oil and wherein the lubricating composition has a shear loss of less than about 15% in the 20 hour taper bearing shear test.

A multigrade oil composition comprising at least 40% by weight of at least one mineral oil, having a kinematic viscosity of at least about 8 cSt at 100° C., (A) from about 15% to about 40% by weight of at least one polyalkylene or derivative thereof, ethylene alpha-olefin copolymer, ethylene, propylene polymer or mixtures thereof, (B) Up to about 30% by weight of at least one fluidizing agent, the fluidizing agent being selected from alkylated aromatic hydrocarbons, polyalphaolefins having a kinematic viscosity in the range of about 2 to about 30 cSt at 100° C., and mixtures thereof, provided that when the fluidizing agent is a polyalphaolefin having a kinematic viscosity from about 2 to about 30 cSt at 100° C., then the polyalphaolefin is present in an amount up to about 12% by weight, wherein the lubricating composition is a gear oil and wherein the lubricating composition has a shear loss of less than about 15% in the 20 hour Tape Bearing Shear Test.

A lubricating composition comprising at least about 30% by weight of at least one mineral oil having a kinematic viscosity of less than about 8 cSt at 100° C., (A) from about 20% to about 40% by weight of at least one polymer having a {overscore (M)}w less than 50,000, the polymer being selected from polyalkylenes, terpolymers of ethylene, propylene and a diene monomer, and mixtures thereof, and (B) up to about 30% by weight of at least one fluidizing agent, provided that when the fluidizing agent is a polyα-olefin having a kinematic viscosity from about 2 to about 30 cSt at 100° C., then the polyα-olefin is present in an amount up to about 12% by weight, wherein the lubricating composition is free of polyacrylates having a {overscore (M)}w less than 50,000 and wherein the lubricating composition has a shear loss of less than about 15% in the 20 hour taper bearing sheet test.