“Automatic transmissions originally had a feature that allowed push starting, a rear pump in addition to the front pump. If the car was rolling the rear pump would provide pressure even if the engine was not running. Some speed was required 15 to as much 30mph recommended for some makes to transmit enough torque through the torque converter to turn the engine for starting. All automatic cars through 1958 and some into the mid 1960s were push startable, some examples are GM's hydramatic through 1958, Chevrolet's powerglide through 1966, Fordomatic/Cruseomatic through 1963 and some Fords through early 1968, Chrysler's Torqueflite through 1965. Reference "how to push and tow automatic drive cars" inside back cover of MOTOR AUTO REPAIR MANUAL.”