The lubricating composition of this invention is primarily comprised of an admixture of an API Group V base oil component and a polyolefin base oil component. In general, the blend components include at least 45 wt. % of a Group V base oil component having a kinematic viscosity of less than 20 cSt at 100° C., and from 10 wt. % to 60 wt. % of a polyolefin base oil component having a kinematic viscosity of at least 500 cSt and not greater than 4000 cSt at 100° C. The lubricating composition has improved efficiency and lower operating temperatures, comparable to polyalkylene glycol-based lubricant level, which provides improved machine life and seal life, relative to other lubricating compositions.