Chapter 16 Vehicle automatic transmission 同©大学 TONGII UNIVERSTTY Section 1 Overview >Definition of Automatic Transmission:One type of motor vehicle transmission that can automatically change gear ratios of transmission system according the working conditions such as engine load and yehicle speed,so that to make the vehicle to obtain good power performance and fuel economy,and reduce engine emissions ,and improve the driving safety and riding comfort and handling easiness.Chapter 16 Vehicle automatic transmission Definition of Automatic Transmission：One type of motor vehicle transmission that can automatically change gear ratios of transmission system according the working conditions such as engine load and vehicle speed, so that to make the vehicle to obtain good power performance and fuel economy, and reduce engine emissions ,and improve the driving safety and riding comfort and handling easiness. Section 1 Overview