Adjustable tread device for wheels of the same axle

The device has a central cradle (2) integrated to a chassis of a vehicle using a suspension system. Four pivot axles (A-D) are placed on apex of a geometrical assembly forming a parallelogram when projected in a horizontal plane. The parallelogram is deformable to adjust spacing between wheels and to change steering of the vehicle, when a spacing and steering cylinders (7,8) are activated, respectively.