This gear transmits drive from the unloading auger shaft to the metering mechanism that controls grain flow out of the combine tank. It meshes with the mating gear in the transfer case, converting rotational speed to match the auger’s delivery rate. A worn or broken tooth causes intermittent grain flow, leading to uneven unloading or jamming in the discharge tube. The original gear is machined to the same tooth profile and bore tolerance as the factory assembly, so it seats on the shaft without additional shimming. On replacement, inspect the mating gear for wear and ensure the retaining clip is fully seated.