Abstract: A power lift assembly for applying a rotary cranking force to the crank stub of a mechanical window crank in an automobile door is disclosed. The power lift assembly is intended for use in combination with an automobile door having interior and exterior side panels enclosing a compartment, a window mounted for reciprocal movement into and out of the compartment, and a mechanical crank assembly contained within the compartment and coupled intermediate the door and window. The force required to raise and lower the window is developed by an electrical drive motor which is mounted on the interior panel at a remote location relative to the crank stub. The rotary driving force developed by the drive motor is transmitted to the crank stub through a flexible drive shaft and a worm and gear assembly which is coupled directly to the crank stub.