Preferably, an embodiment of a tire inflation system includes at least an axle housing a pressurized fluid, a hubcap supported by the axle and having an interior and an exterior, a rotary union axially aligned with the axle and mounted to the hubcap from the exterior of the hubcap, and a lubrication trap axially aligned with the axle, supporting the rotary union and secured to the hubcap from the exterior of the hubcap for rotation with the hubcap. In another embodiment, a tire inflation system includes at least an axle housing a pressurized fluid, a hubcap supported by the axle and having an interior and an exterior, a rotary union axially aligned with the axle and mounted to the hubcap from the exterior of the hubcap, and a bushing axially aligned with the axle and disposed between the rotary union and the hubcap.