Abstract: A tiltable trailer is disclosed having a wheel-mounted chassis with a frame element (3) pivotable between a horizontal travelling position and a backwardly-downwardly inclined position. The frame element (3) has longitudinal guide (12, 12') along which a basic frame (2) is displaceable, the basic frame being included in each of a plurality of different add-on units forming a series, and, locking device (16) for securing, at least in the travelling position, the basic frame (2) to the pivotable frame element (3), the trailer further having a winch (23) by means of which the basic frame (2) can be hauled up on the inclined frame element from a position behind the frame element to a position coinciding with that of the frame element, in which latter position the locking device can secure the basic frame to the frame element.