Abstract: A trailer for transporting large machinery such as farm combines and the like. The trailer comprises a main or center portion flanked laterally by side portions, each side portion comprising a plurality of outwardly telescoping sections which form runways to receive the wheels of the machinery. The trailer wheels and towing gear are attached to the main portion. The side sections are extendable to accommodate equipment having a wide wheel-span. Each of the three side sections on each side, can be separately extended or retracted by a single person. An alignment system is provided to facilitate alignment of the three sections. A chain limits the outward extension of the side sections. Locking pins hold the side sections in their inner positions.