A grain tank for an agricultural harvester includes a floor, a plurality of upstanding walls, and an unloading conveyance. The floor has a plurality of side edges. Each wall has a lower edge positioned along a corresponding side edge of the floor. The unloading conveyance has an inlet in communication with an interior of the grain tank adjacent to the floor. At least one of the walls of the grain tank is movable relative to the floor between an expanded harvest position and a folded transport position.
