This oil seal fits into the gearbox housing to retain lubricant and exclude contaminants from the rotating shaft. It sits at the shaft exit point inside the transmission case, where it prevents fluid loss and keeps debris from entering the gear train. A worn seal allows oil to weep past the shaft, leading to low lubricant levels and accelerated gear wear. Corteco manufactures this seal to match the original housing bore and shaft diameter, so the sealing lip contacts the shaft at the correct interference for consistent sealing pressure. On installation, ensure the seal face is square to the bore and lubricate the lip before pressing it home.