A spare tire winch mechanism which performs the steps of lowering the spare tire from its location and locating the flat tire on this location via a rope winding assembly. A worm gear and a threaded drum prevent the rope from winding onto the threaded drum in an overlapping and irregular manner which results in locking of the parts and the damage to the parts due to the application of extreme force during the winding. The spare tire performs free fall movement with its own weight as a result of the tire wrench being activated with a pulling force applied perpendicular to the floor axis and the worm gear disconnects from the drum body, in case one of the tires of the motor vehicle needs to be changed.