<p>A front wheel drive shaft is connected to a sun gears disposed at the center of each front wheel. The front wheel is rotated by rotating a ring gear disposed on the outer periphery of planetary gears through the planetary gears disposed on the outer periphery of the sun gear. Stays provided at the upper and lower ends of the steering knuckle in the front wheel are connected to the outer ends of upper and lower suspension arms respectively through spherical joints. The right and left front wheels are so provided on a work vehicle that those front wheels are capable of steering and can be separately swung in the vertical direction of the vehicle.</p>
