A wheel support structure includes two individual wheel arms (42, 44) tied together by a linkage (52, 54, 52, 54) that pivots about a fore-and-aft extending axis (112, 114, 124) at a location above the wheels (18w) and generally above the plane of the implement frame (12). The linkage constrains the wheel arms (42, 44) to pivot in opposite vertical directions as the implement (10) moves over irregular ground surfaces to improve weight distribution on the wheels (18w). Spring structure (152, 154) may be interposed between the ends of the pivoting linkage (52, 54, 52, 54) and the individual wheel arms (42, 44) to lower frame impact forces. The structure (52, 54, 52, 54) allows two wheels (18w) to be placed side-by-side with their axes (18a) generally aligned and reduces under-frame hardware to improve crop and soil and trash flow.
