This complete gearbox assembly drives the grain unloading auger system on a combine harvester. It transfers torque from the hydraulic motor to the discharge auger, controlling the flow of grain from the tank to the unloading tube. A worn or damaged gearbox causes irregular auger rotation, leading to uneven unloading speed or complete driveline failure. This assembly is built to the manufacturer's original specifications, matching the housing geometry and gear ratios of the original unit so no adapter plates or shaft modifications are needed. On installation, verify the input shaft aligns with the hydraulic motor coupling and fill the housing with the specified lubricant before operation.