In order to reduce the breakdown and improve the performance of automobile, the performance of bearing is more and more important. Now, about 100-150 bearings are playing a role in the vehicles with mainstream engines. In this paper, we take the automobile transmission and differential gear as an example to explain how the bearing is used in the automobile. Figure 1 device for transmitting engine power to axle Bearings used in transmission In the transmission, different types bearings play their own characteristics. In the automobile parts, many bearings are also used. Transmission can be divided into manual transmission and automatic transmission. In vehicles with manual transmission, the operating lever is set in the driver's seat. Fig. 2 operating lever for manual transmission The operator manually operates the gear lever to change the engine power into driving force suitable for driving conditions. The manual transmission consists of shaft and gear. The...