Abstract: A multi-piece siderail is fabricated for use as a truck frame which has potential cost and weight reductions while also providing superior weight loading characteristics. Each section of the multi-piece siderail includes a webbed portion having longitudinal ribs that form alternating protruding and recessed sections. An upper and a lower flange are provided on each section and each flange is formed with a stepped, lipped configuration. The unique structure of each section provides increased rigidity and support to that section and also allows for a nesting arrangement between each of the three components. Furthermore, this structure provides multiple attachment zones throughout the frame—two zones on each flange and three zones on the front and rear section webs and five zones on the center section web. Each of these attachment zones are surrounded by a work hardened corner to provide reinforcement.