Abstract: In a sliding door for a vehicle having an opening in at least one side thereof, the sliding door is connected to the vehicle for non-linear movement along a fixed path between an open position and a closed position with respect to the opening. The fixed path is defined by an upper guide track, a lower guide track, and an intermediate guide track. Each elongate guide track has an identical generally C-shaped cross-section with an elongate slot opening through a lower surface. At least one guide member is engagable within each track for guiding the sliding door while moving in either direction between the open position and the closed position with respect to the opening in the vehicle. Preferably, at least one load bearing roller is provided on each door mounting bracket, or at least two load bearing rollers are provided on two of the three door mounting brackets.