Abstract: A hidro-pneumatic piston traction controller is implemented inside a differential (1-2) that contains a pressurized piston (10) in which are situated the planet gears (3) and satellites gears (4) of the differential. The planet gears are in intimated contact with the internal wall of the differential case (1 and 2) by means of the ring gears (6). In case of changing separator (9) by a separator with pistons, the ring gears (6) are in contact with the head of the planet gears (3). The pressure and friction condition inside the differential case do not affect the normal torque transmission lobbied to the wheels; even though the vehicle turns to a high speed, but oppose to the excessive acceleration and speed of some planet gear when the corresponding wheel slides, loosing grip over the asphalt or terrain.