Abstract: A steering axle assembly for a motor vehicle, including an axle, at least one king pin mounted at one end of the axle, a pivotal steering knuckle having a bore rotatably receiving the king pin, a closure cap mounted on the steering knuckle for closing the bore, and an annular sealing element disposed between the end cap and the knuckle. The end cap includes an annular recess for receiving a portion of the sealing element, a central, lubricant reservoir in alignment with the bore, and a lubricant check valve which permits lubricant to pass only outwardly from the reservoir.