He is a car crusher used in the same junkyard as his assistants, the Crane and Magneto. As his name suggests, he is a large crushing machine designed only for crushing cars. Since the Crusher needs the Magneto to be able to accomplish this, it is likely that he and the Magneto are both part of the same body. Like the Crane and Magneto, the Crusher can speak by singing "Worthless", but like Street Lamp and Traffic Signal, whereas most appliances and the Junkyard Cars can move, he seriously can not. Its only moving components are the conveyor belt that brings its victim cars to him, and an upper mandible piston which proceeds to crush them into cubes.
He is first seen in the Luxo, Jr.'s dream. He appears after Luxo, Jr. is chased by the several giant balls. He looking very evil at the situation to crush Luxo, Jr. into the cube. As Luxo, Jr is killed by the crusher, he and his friends are awoken by a loud thunderclap, bringing him out of his nightmare.
He is later seen ordering Magneto to catch Luxo, Jr. and the appliances into the junkyard.
He appears near the end of the film, when the main characters are sent to The Junkyard, an automotive junkyard. As they are about to be killed by the crusher, Luxo, Jr. jumps into the workings of the machine, using his own body to jam its gears. Crusher is disabled just in time, and the Luxo, Jr. is repaired by the Master.