But to do that, you will have to push the car at the speed of around 25-40 miles per hour, which is fairly impractical. If you choose to propel the car by attaching it to another vehicle, it may become difficult to control it, as you would need to push it down a steep slope to reach this speed. Because Automatic Car Gears have more complexity than the manual ones, the car becomes more difficult to predict and propel as well, and may lead to unexpected damage. So, though this is a possible option, it is unsafe and not possible most of the times. here