What does AT stand for in cars?

1 Answers
RafaelMarie
07/30/25 9:50am
AT in cars stands for Automatic Transmission. Automatic transmission, also known as automatic gearbox, is a transmission device that can automatically shift gears based on the vehicle's speed and engine RPM, as opposed to manual transmission. It consists of a torque converter, planetary gear transmission, and control mechanism. Depending on the working principle, automatic transmissions can be categorized into: 1. Hydraulic Automatic Transmission: Achieves automatic shifting through hydraulic transmission and planetary gear combination; 2. Mechanical Continuously Variable Transmission (CVT): Characterized by a continuous gear ratio rather than discrete points, improving overall fuel economy; 3. Electronically Controlled Mechanical Automatic Transmission: Uses an automatic shifting system to operate the clutch and select/shift gears; 4. Dual-Clutch Transmission (DCT): Employs two sets of clutches that work alternately to achieve seamless gear shifting.
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