A power drive system is adapted for a sliding door mounted on at least one side of a vehicle for sliding movement forwardly and rearwardly of the vehicle. The system includes a reversible motor. A bracket is guided within a guide along a fixed path between the opened and closed positions of the door. An elongated drive member is slidably disposed within the guide and connected to the bracket at one end for driving the bracket along the fixed path. A translator mechanism operably engages with the drive member for powering movement of the door. The translator mechanism can include a rotatable hub, operably engageable with the drive member, a gear transmission for driving the hub, and a clutch mechanism for connecting the motor to the transmission. The translator mechanism preferably has sufficient power to pull the sliding door into a primary latch position with respect to the corresponding portions of a latch mechanism attached to the door and frame defining the door opening. A power striker moves the door into and out of sealing engagement with the frame. A lock mechanism selectively maintains the latch in a locked position. At least one sensor provides an input signal to a control system corresponding to movement of the door, position of the lock mechanism, and position of the power striker for controlling the door drive unit, power striker drive unit, and lock mechanism drive unit in accordance with a program stored in memory.