Abstract: An improvement to a sliding door system for a shower-bathtub installed adjacent to three walls of a bathroom. The sliding door system includes an upper track that has the following elements: (1) at least two wheel supports, (2) at least two wheel stays positioned above the two wheel supports, and (3) at least two lower bearing supports positioned at least five inches below the two wheel supports. The upper track is rigidly attached to the two short walls of the shower-bathtub and provides enough support so that the presence of a lower track is unnecessary. In a preferred embodiment, the outside wall of the bathtub and the two short shower walls comprise molded dams.