Abstract: A wheeled vehicle of good stability and high manoeuvreability is disclosed. The vehicle is hydraulically driven and skid-steerable by rotation upon one only, transverse pair of wheels, herein called the pivot wheels, all other wheels being allowed to slide laterally into each new position; and is provided with automatic loading means operative upon the pivot wheels to ensure that ground pressure at these two wheels is always greater, under all drive conditions, than at any other of the wheels. The wheels are articulated to the vehicle frame to absorb irregularities in terrain and provision is also made for adjusting the fore and aft angle of the frame with respect to the wheels for hill climbing or descending.