To enable automatic control of level attitude in the transverse direction and attitude amendment for a machine body sinking due to the uneven hardness of a rice paddy while reducing the vibration of the machine body, in a vehicle running with an endless caterpillar track such as a harvester.

A running track device equipped with a pair of right and left endless caterpillars is interlocked with a balancing mechanism so that both of them may be lifted and lowered synchronously by a first hydraulic mechanism 18. In addition, a second hydraulic mechanism 23 capable of lifting and lowering either of them is set in this interlockable balansing mechanism. Further, a first hydraulic switching valve 25 for the first hydraulic mechanism 18 and a second hydraulic switching valve 26 for the second hydraulic mechanism 23 are automatically controlled through a controller CPU to keep the machine body in a certain height range and horizontally in relation to the ground surface of the rice paddy based on the signals from a sinking detector S1 for detecting the depth below the surface of the rice paddy sunk due to the weight of the machine body and from an inclination detector S2 for detecting the unbalance of the machine body between the right and left sides.