A steering and suspension arrangement for agricultural vehicle includes a horizontal axle transverse to the direction of movement with the ground wheel mounted at each end of the axle. The length of the axle can be adjusted by extending and retracting end portions of the axle relative to a centre section of the axle. Each end of the axle carries a wheel hub on a suspension arrangement defined by an upper plate, a lower plate, a first channel member attached to the lower plate and a second channel member attached to the upper plate with the channel members facing each other and connected by two parallel pivoting links. Between the plates is mounted a gas bag spring. The frame is divided into a front portion and a rear portion which are held against steering movement but can pivot, each relative to the other about a horizontal axis along the direction of travel to accommodate twisting beyond the limited suspension movement. The steering is effected by steering movements of the front wheels controlled by two separate cylinders which are arranged in a hydraulic circuit which automatically compensates for any fluid leakage to maintain the wheels aligned.