An axle is a shaft on which the wheels revolve. A full-floating axle is used to drive the rear wheels. It does not hold them on nor support them. A semi or one-quarter floating axle is used to drive the wheels, hold them on, and support them. A three-quarter floating axle is used to drive the rear wheels as well as hold them on, but it does not support them. A live axle holds the wheels and transmits power to the wheels. A dead axle or beam axle merely holds the wheels, but does not transmit power to the wheels. Also see, Dropped axle , Elliot type axle , Full-floating axle , Live axle , Low pivot swing axle , Rear axle housing , Rear axle ratio , Reverse-Elliot type axle , Semi-floating axle , and Swing axle .