This oil seal sits at the outer end of the front planetary gear housing, retaining lubricant inside the final-drive assembly while excluding dirt and moisture from the wheel-end environment. It seals the rotating shaft against the stationary housing, maintaining the oil film that the planetary gears and bearings require for proper load distribution. A leaking seal allows gear oil to escape, which leads to insufficient lubrication and accelerated wear on the planetary set. Corteco manufactures this seal to match the original housing bore and shaft journal geometry, so the sealing lip contacts the shaft at the correct interference and angle without requiring additional shimming or adapter sleeves. On reinstall, ensure the housing bore is clean and free of burrs, and press the seal squarely to the shoulder depth.