Abstract: A spiral groove flow passage with a clockwise spiral direction and a spiral groove flow passage with a counterclockwise spiral direction are provided inside a spindle. When the spindle is accelerated to rotate in the forward rotation direction, a pressure in the direction of causing a reverse flow of a coolant is applied to the left-hand spiral groove flow passage by the axial-flow pumping action, but a pressure in the forward direction is applied to the right-hand spiral groove flow passage by the same axial-flow pumping action to cancel out the pressure causing the reverse flow described above.

Abstract: A wheel hub and bearing assembly for use on the ends of a stationary axle and particularly on tractor and trailer axles. A wheel hub, a pair of bearings, a bearing spacer and seals are assembled and installed on the axle end. The bearing spacer is positioned between the pair of bearings and has one or more vanes mounted thereon for redirecting the flow of lubricant disposed in a cavity in the wheel hub between the bearings in a bi-axial flow direction towards each spaced bearing to lubricate and cool the bearings.