Abstract: Railway vehicle trucks having at least two wheel-sets, each with a live axle mounted in a respective pair of bearings, at least one axle bearing of one wheel-set being elastically interconnected with at least one axle bearing of the other wheelset through bracing structure providing bracing between the wheel-sets. Side frames are connected to respective axle boxes via a primary spring mounting and each side frame is of fabricated construction constituting a bridge member of I-section form which a sub-frame depends, the bridge member and sub-frame defining a space therebetween into which respective side flanges of a bolster project, each said side flange being supported by the respective sub-frame via a secondary spring mountings.