A drive mechanism of a front-wheel drive vehicle adapted to selectively drive the rear wheels includes an overrunning clutch mounted coaxially with the rear axleshafts. The clutch and drive mechanism are lubricated by way or ports formed in the casing that carry lubricant thrown radially outward by a bevel pinion rotating through the oil bath to a chamber that is baffled to permit only a portion of the lubricant to flow from the chamber through bearings that support the rear axleshafts. Helical recesses are formed on a portion of the axleshafts and pump lubricant from the chamber axially inward into interior abutting surfaces of members that rotate relative to adjacent members. The pressure head produced by the hydraulic pump, according to this invention, forces the fluid through the roller-race assembly and through spline connections radially outward against a drag connection between the race and a ground connector. The lubricant is pumped radially outward and carried in that direction toward the oil ports formed in the casing by a bevel pinion rotating within the oil sump.