A self-unloading pipe trailer carries a rack of pipe and automatically unloads segments as it moves along a pipeline location. A single operator can maneuver the trailer and operate the unload controls. In unload mode, the operator drives along the pipeline and the trailer unloads the segments automatically. The trailer employs a power pipe rolling assembly that engages with weight-bearing tires in order to translate the distance traveled across the ground to directly power a pipe unloading system such that each foot of ground travel equates to a foot of pipe unloading. If the operator needs to change speed and/or stop, it can be done without modifying the unload mode as the dispensing process automatically responds to the change in speed. There is no complex externally powered unloading system to break-down, lose timing, or otherwise complicate matters. Pipe is simply unloaded automatically as the trailer moves down the pipeline.