Lubricating oil composition for automatic transmissions

A lubricating oil composition for automatic transmissions, the lubricating oil composition comprising:

• a low viscosity base oil at a concentration of 60% to 98% by mass,
• wherein the low viscosity base oil comprises one or more of a Group 2 base oil, a Group 3 base oil, and a Group 4 base oil, with each of the Group 2 base oil, the Group 3 base oil, and the Group 4 base oil being categories defined by the American Petroleum Institute,
• wherein the low viscosity base oil has a kinematic viscosity of 2 mm2/s to 5 mm2/s at 100° C., and
• wherein at least 45% by mass of the low viscosity base oil comprises at least one Fischer-Tropsch synthetic oil;
• a high viscosity base oil at concentration of 1% to 20% by mass,
• wherein the high viscosity base oil comprises a metallocene/poly-α-olefin, and
• wherein the high viscosity base oil has a kinematic viscosity of a 100 mm2/s to 600 mm2/s at 100° C.;
• and
• a polymethacrylate at a concentration of 1% to 20% by mass, wherein the polymethacrylate has a molecular weight of 10,000 to 50,000 by weight-average,
• wherein the lubricating oil has:
• a kinematic viscosity of 5 mm2/s to 7 mm2/s at 100° C.;
• a viscosity index of at least 190;
• a low temperature (−40° C.) Brookfield viscosity of not more than 5000 mPa·s;
• a rate of reduction of not more than 3% as measured by a KRL shear stability test of a 100° C. kinematic viscosity;
• and
• an evaporation loss of not more than 10% by mass as measured by the NOACK method for 200° C./hour.