This self-aligning spherical roller bearing supports a rotating shaft in the threshing or separating drum of a grain harvester. It accommodates angular misalignment between the shaft and the housing, which occurs as the drum deflects under load. The bearing’s spherical outer raceway allows the inner ring to tilt, maintaining contact with the rollers and distributing load evenly across the raceway. A worn bearing produces radial play that causes the drum to wobble, leading to uneven crop flow and increased vibration in the support structure. The C3 internal clearance is specified for applications where thermal expansion of the shaft is expected during operation. On installation, ensure the housing bore is clean and free of burrs, and press the bearing onto the shaft using the inner ring face only to avoid brinelling the rolling elements.