Abstract: A self-propelled unit comprises a work facilitating implement coupled to a high-clearance chassis vehicle, the implement being provided with a support for supporting it on longitudinally and horizontally extending flanges fixed on the chassis. The vehicle is relatively movable between the support of the vehicle and the implement to allow disengagement of the latter from the vehicle by longitudinal movement of the vehicle relative to the implement when the latter is supported on the ground, the relative movement being effected independently of the implement support and providing for support of the chassis on the ground.