An automatic transmission system is a new technology in the gear box of the vehicles. The driver can automatically change gear ratios as the vehicle moves, freeing the driver from having to shift gears manually. Most automatic transmissions have a defined set of gear ranges, often with a parking pawl feature that locks the output shaft of the transmission. Bassicaly the Automatic transmission system uses in heavy duty vehicles and it effected to mileage. After fit this system the vehicle has more weight than manual.
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