Abstract: A framework is provided for a relatively large off-highway truck which has front wheels supported by independent suspension struts positioned on opposite sides of the engine. The framework includes a pair of longitudinally disposed, laterally spaced main side rails and a superstructure which provides an upper, transverse bridgework interconnecting the side rails to add transverse rigidity in a manner which does not obstruct overhead accessibility to the engine. The superstructure also provides radial support for the upper ends of the struts to minimize twisting of the main side rails by moment loads created by the wheels. The superstructure further supports a roll-over protective structure for the operator cab of the truck in a manner which minimizes the transmission of severe impact loads in the event of rollover to the main frame.