The invention relates to a motor vehicle (1) comprising a chassis frame (2), a platform (5) and at least one folding side (6) movable between a raised position and a lowered position. The platform (5) comprises a stationary portion (50) and at least one lateral movable portion (51) vertically movable between a high position, in which it is flush with the stationary portion (50), and a low position, in which it has been lowered, there being provided means (7) for controlling the vertical movement of the at least one movable portion (51). The or each folding side (6) is connected to a respective movable portion (51) in such a way that they are vertically movable in one piece while the folding side (6) is in the lowered position.