In the past, single row tapered roller or ball bearings were used most frequently in automobile hub bearings. With the development of technology, the car hub unit has been widely used. With the increasing use of hub bearing unit, it has developed to the third generation: the first generation is composed of double row angular contact bearing. The second generation has a flange for fixing the bearing on the outer raceway, which can simply fix the bearing sleeve on the axle with nuts. Make the maintenance of the car easier. The third generation hub bearing unit adopts bearing unit and anti lock brake system ABS. The hub unit is designed with an inner flange and an outer flange, the inner flange is fixed on the drive shaft with bolts, and the outer flange installs the whole bearing together. Worn or damaged hub bearing or hub unit will cause improper and high cost failure of your vehicle on the road, and even cause damage to your safety. Please pay attention to the following matters in the use and installation of hub bearing:

1. In order to ensure safety and reliability to the greatest extent, it is recommended that you always check the hub bearing no matter how old the vehicle is - pay attention to the early warning signal of bearing wear: including the friction noise during any rotation or the abnormal deceleration of suspension combination wheel during turning. For rear wheel drive vehicles, it is recommended to lubricate the front hub bearing when the vehicle reaches 38000 km. When replacing the brake system, check the bearing and replace the oil seal.

2. If you hear the noise from the hub bearing, first of all, it is important to find the location where the noise occurs. There are many moving parts that may produce noise, or some rotating parts may contact with non rotating parts. If the noise in the bearing is confirmed, the bearing may be damaged and needs to be replaced.

3. Since the working conditions of bearing failure on both sides caused by the front hub are similar, it is recommended to replace in pairs even if only one bearing is damaged.

4. The hub bearing is relatively sensitive, so it needs to adopt correct methods and appropriate tools under any circumstances. During storage, transportation and installation, the components of the bearing shall not be damaged. Some bearings need to be pressed in with high pressure, so special tools are needed. Be sure to refer to the car manufacturing instructions.

5. When installing the bearing, it should be in a clean and tidy environment. The small particles entering the bearing will also shorten the service life of the bearing. It is very important to keep a clean environment when replacing bearings. It is not allowed to knock the bearing with a hammer, and pay attention not to drop the bearing on the ground (or similar improper handling). Before installation, check the condition of the shaft and bearing seat. Even small wear will lead to poor matching, which will lead to early failure of the bearing.

6. For the hub bearing unit, do not attempt to disassemble the hub bearing or adjust the sealing ring of the hub unit, otherwise the sealing ring will be damaged and water or dust will enter. Even the seal ring and the raceway of the inner ring are damaged, resulting in the permanent failure of the bearing.

7. There is a magnetic thrust ring in the sealing ring equipped with ABS device bearing, which can not be collided, impacted or collided with other magnetic fields. Take them out of the box before installation and keep them away from the magnetic field, such as the motor or electric tools used. When these bearings are installed, the operation of the bearings is changed by observing the ABS alarm pin on the instrument cluster through the road condition test.

8. For the hub bearing equipped with ABS magnetic thrust ring, in order to determine which side the thrust ring is installed on, you can use a small light thing * close to the edge of the bearing, and the magnetic force generated by the bearing will attract it. During installation, point the side with magnetic thrust ring to the inside, which is facing the sensitive elements of ABS. Note: improper installation may cause the function of the brake system to fail.

9. Many bearings are sealed, and this kind of bearing does not need to be greased in the whole service life. Other unsealed bearings, such as double row tapered roller bearings, must be greased during installation. Due to the different size of the bearing cavity, it is difficult to determine how much grease to add. The most important thing is to ensure that there is grease in the bearing. If there is too much grease, when the bearing rotates, the excess grease will leak out. General experience: when installing, the total amount of grease should account for 50% of the bearing clearance 10. When installing the lock nut, the torque varies greatly due to the different bearing types and bearing seats.