A notch communicating a pair of pockets adjacent to each other in the circumferential direction of pockets of a retainer is provided in a range from an end section on the axially one side to the axially intermediate section of each of pillar portions of the retainer for an angular contact ball bearing, the notch having a substantially rectangular opening shape as seen from the circumferential direction, and an inner surface of the notch having an outer diameter side flat surface portion arranged on the radially outer side from the center of a pocket and extending substantially linearly in the axial direction, an inner diameter side flat surface portion arranged on the radially inner side from the center and extending substantially linearly in the axial direction, and a back side flat surface portion arranged on the axially other side from the center and extending linearly in the radial direction.

An axle assembly having a wheel mount that is disposed on a planet carrier of a planetary gear set. The wheel mount may be fixedly positioned with respect to the planet carrier with one or more fasteners and one or more dowels so that the wheel mount and planet carrier may rotate together about an axis.

An axle assembly having a wheel mount that is disposed on a planet carrier of a planetary gear set. The wheel mount may be fixedly positioned with respect to the planet carrier with one or more fasteners and one or more dowels so that the wheel mount and planet carrier may rotate together about an axis.