This truck comprises: a) a chassis (5) articulated on the body in a manner that enables it to pivot about a vertical axis; b) on either side of this axis, two transverse structures (8a, 8b) supported by said chassis with the ability to pivot about a vertical axis (14), and c); swing arms (10) supporting, at one of the ends thereof, a wheel (12) independent of the others, each arm (10) being articulated by its other end on a horizontal and transverse axis of one of the transverse structures. According to the invention, the vertical articulation (14) on the chassis (5) of each transverse structure (8a, 8b) supporting the swing arms (10) is joined to or at least near the articulation (4) of this chassis (5) on the vehicle body, whereas each structure (8a, 8b) is associated with assisting, pneumatic or hydraulic means controlled by means that compare a reference geometrical axis of the truck with a reference geometrical axis of the vehicle body.