PURPOSE: To adjust the locus of a rear car when a connected car is turned, by installing a steering mechanism linked with the turn of a turntable onto the rear car of the connected car.

CONSTITUTION: A push button 107 is pressed when front and rear cars 2 and 3 are in normal traveling state or in turning state. Then, a servo motor 100 operates to set the lever ratio to the middle position. When a front-side member 24 is turned in this state, the control lever 95 of a control valve 82 swings to the middle position through a link 83, and the piston rod 88 of a hydraulic cylinder 80 is slided, and a wheel W is turned to the middle position through a knuckle arm 90. When the front-part car 2 is turned leftward, the wheel W of the rear car 3 is turned rightward, and the rear wheel W passes on the same locus to that of the front wheel. The locus of the rear car 3 can be set outside of inside the front car 2 by varying the lever ratio by selecting push buttons 106 and 108.