This bushing sits in the cutterbar drive of the parent combine, acting as a wear surface between the rotating shaft and the stationary housing. It maintains the correct radial alignment of the drive components, preventing metal-to-metal contact that would accelerate wear on the shaft or housing bore. A worn bushing allows play in the drive, which can cause vibration and uneven cutting at the header. The bushing is machined to the original inner and outer diameter tolerances so it fits the bore without reaming and accepts the shaft without excessive clearance. On installation, ensure the bushing is fully seated and lubricated before the shaft is inserted.