Abstract: An all-wheel-drive vehicle, particularly a fork-lift truck suitable for use on rough terrain, with at least one wheel steerable over an angle of substantially 90.degree. in each direction. To avoid wheel slip, drive motors of the vehicle are arranged to provide a differential action between steerable and non-steerable wheels at intermediate steering angles, and to transmit drive only to the steerable wheel or wheels at large steering angles approaching or at 90.degree.. The drive motors are preferably hydrostatic with an individual hydraulic motor for each wheel.