This oil seal sits in the header assembly of a self-propelled forage harvester or combine. It seals the rotating shaft against fluid leakage and prevents contaminants from entering the bearing cavity. A worn or hardened seal allows lubricant loss and ingress of debris, which accelerates bearing wear and can lead to shaft scoring. The manufacturer machines this seal to the original housing bore and shaft diameter tolerances, so it seats correctly without additional shimming. On installation, ensure the sealing lip faces the lubricant side and that the housing bore is clean and free of burrs.