A railcar bogie includes: a cross beam supporting a carbody; a pair of front and rear axles sandwiching and arranged in front of and behind the cross beam in a railcar longitudinal direction to extend in a railcar width direction; bearings provided at both railcar width direction sides of each and rotatably supporting the axles; axle boxes accommodating the bearings; side members extending in the railcar longitudinal direction supporting both railcar width direction end portions of the cross beam and each including both railcar longitudinal direction end portions supported by the axle boxes; contact members provided at both railcar width direction end portions and disposed on railcar longitudinal direction middle portions of the side members so as not to be fixed to the side members in an upper-lower direction; and supporting members provided at the axle boxes and supporting the railcar longitudinal direction end portions of the side members.

An improved leaf spring side bearing assembly for railway freight cars is provided that achieves improved tracking and curving by the limitation of rock of the railway freight car. The side bearing comprises a base with two raised end sections. A leaf spring assembly is provided on the base that extends to the underside and support channel of the freight car. A top wear plate and a bottom travel stop are also included with the leaf spring side bearing assembly.