A beam axle is the most commonly used type of front suspension, due to its appearance when exposed without fenders on a vehicle with open front suspension. Independent front suspension is rarely used and most rat rods use a 1928-1948 Ford I-beam axle, with a transverse leaf spring. Although any rear axle can be used in a rat rod, the Ford rear end has been preferred for years due to the availability of spare parts. ""...Ford 9-inchers are the most used rear ends in nearly every form of racing and most high-performance street vehicles ...""