The wagon has a loading space comprising a floor conveyor (5) limited by a front wall (7) at front side. The floor conveyor is pivotable with a hydraulic cylinder (9) that comprises a pressure sensor (9a), which actuates displacement of the floor conveyor and/or the front wall when reaching a predetermined pressure value. The pressure sensor is coupled with a control device (10) that is arranged in a cabin of a tractor. The front wall is trough-shaped, and a central portion extends forward than side walls (6). The front wall is pivotable on a conveyor rotor (8) about horizontal axis.