The wheel hub oil seal is a daily car maintenance. The number of times the car oil seal may be replaced belongs to the auto parts with a large amount of consumption. The oil seal can also be called the oil baffle. Among many auto parts, many are installed with oil seals, such as on the car. Parts such as rolling bearings or sliding bearings, etc., are used to prevent the leakage or leakage of lubricating oil or other oils, as well as prevent dust from infiltrating, maintain good lubrication conditions for rolling or sliding friction parts, and prolong service life. . Engine: Crankshaft – crankshaft front and rear oil seals, valves – valve oil seals, transmission – transmission front and rear oil seals, transfer case – transfer case front and rear oil seals and other parts of the car need oil seals.