Increased Capacity Railcar and Method

A railway car includes a railway car underframe having a first longitudinal side sill and a second longitudinal side sill with at least one sidewall assembly disposed along the first longitudinal side sill of the railway car underframe. The sidewall assembly is formed in part from a side sheet, an interior vertical support post, and an exterior vertical support post. A first end of the interior vertical support post and a first end of the exterior vertical support post are each respectively disposed adjacent to the first longitudinal side sill of the railway car underframe. The exterior vertical support post is coupled to an exterior surface of the side sheet. The interior vertical support post is coupled to an interior surface of the side sheet.