A load-carrying truck having a fork lift mechanism mounted on a chassis, the chassis having a front end and a rear end and a left and a right side, the truck comprising: a pair of front wheels (24, 26) each disposed towards the front end of the chassis, one on the left side and the other on the right side, and a single rear wheel disposed towards the centre of the rear end of the chassis, wherein at least one of the front wheels (24, 26) is driven and steerable and the rear wheel is driven and steerable, wherein the truck is operable in: a forward/reverse mode of operation with the front wheels (24, 26) aligned generally parallel to the front-rear axis of the chassis and with steering controlled by steering the rear wheel which is in a neutral steering position when parallel with the front wheels (24, 26), and a sideways mode of operation with the rear wheel aligned generally perpendicular to the front-rear axis of the chassis and with steering controlled by steering the at least one of the front wheels which is in a neutral steering position when parallel with the rear wheel, the truck further comprising an electrical motor control system for driving the at least one front wheel and the rear wheel at varying speeds of rotation relative to one another, wherein when the truck is operated in said forward/reverse mode or said sideways mode with neutral steering, the electrical motor control system drives the at least one front wheel (24, 26) and the rear wheel at rotational speeds proportional to one another in inverse relation to the ratio of the front and rear wheel diameters; characterized in that when the truck is operated in said forward/reverse mode of operation and is steered in the direction towards the side on which the at least one driven front wheel (24, 26) is located, the relative speed of that wheel is decreased progressively in dependence on the angle of steering of the rear wheel such that the front wheel comes to a stop when the axis of rotation of the rear wheel intersects the front wheel position, and the front wheel (24, 26) is driven in reverse at increasing speeds as the axis of the rear wheel passes said point of intersection with further increasing steering angle; and in that when the truck is operated in said sideways mode of operation and is turned in the direction towards the rear end of the chassis, the relative speed of the rear wheel is decreased progressively in dependence on the angle of steering of the at least one steered front wheel (24, 26) such that the rear wheel comes to a stop when the axis of rotation of the at least one steered front wheel intersects the rear wheel position, and the rear wheel is driven in reverse at increasing speeds as the axis of the steered front wheel passes said point of intersection with further increasing steering angle. a pair of front wheels (24, 26) each disposed towards the front end of the chassis, one on the left side and the other on the right side, and a single rear wheel disposed towards the centre of the rear end of the chassis, wherein at least one of the front wheels (24, 26) is driven and steerable and the rear wheel is driven and steerable, wherein the truck is operable in: a forward/reverse mode of operation with the front wheels (24, 26) aligned generally parallel to the front-rear axis of the chassis and with steering controlled by steering the rear wheel which is in a neutral steering position when parallel with the front wheels (24, 26), and a sideways mode of operation with the rear wheel aligned generally perpendicular to the front-rear axis of the chassis and with steering controlled by steering the at least one of the front wheels which is in a neutral steering position when parallel with the rear wheel, a forward/reverse mode of operation with the front wheels (24, 26) aligned generally parallel to the front-rear axis of the chassis and with steering controlled by steering the rear wheel which is in a neutral steering position when parallel with the front wheels (24, 26), and a sideways mode of operation with the rear wheel aligned generally perpendicular to the front-rear axis of the chassis and with steering controlled by steering the at least one of the front wheels which is in a neutral steering position when parallel with the rear wheel, the truck further comprising an electrical motor control system for driving the at least one front wheel and the rear wheel at varying speeds of rotation relative to one another, wherein when the truck is operated in said forward/reverse mode or said sideways mode with neutral steering, the electrical motor control system drives the at least one front wheel (24, 26) and the rear wheel at rotational speeds proportional to one another in inverse relation to the ratio of the front and rear wheel diameters;