An unload auger assembly (58) for a combine harvester (10) includes a drive coupler (64) configured between adjacent first and second auger segment (62)s. The coupler includes a driver component (70) and associated driver cog (74) coupled to the first auger segment (60). A driven component (78) and associated driver cog (80) is coupled to the second auger segment (62). The driver cog (80) is rotationally engaged by the driver cog (74) to transmit rotational drive from the first auger segment (60) to the second auger segment (62). A friction clutch (84) is configured in-line between the driver component (70) and driven component (78) and rotationally couples the driver component (70) to the driven up to a release torque value wherein the friction clutch (84) disengages the driver component (70) from the driven component (78).
