Abstract: A chassis for a vehicle having three large diameter, low soil pressure tires includes two elongate linear side rails which diverge from one another from back to front and are spaced far enough apart at the front to house a large engine and more closely at the rear to reduce the wheel span. A special front portion to which the front wheel assembly and associated steering means are mounted is constructed of beam-like members extending forwardly and upwardly from the side rails. The beamlike sides of the front portion are bent to forwardly approach one another, terminating at a bearing which receives a mounting yoke carrying the front tire.