A constant contact side bearing assembly for a railcar including a housing with wall structure defining a central axis for the side bearing assembly and a multipiece cap. The cap is arranged in operable combination with the housing and includes a movable first member and a movable second member carried by the first member. A spring resiliently urges the cap members toward railcar body structure. The cap members define cooperating angled surfaces therebetween for urging wall structure on the first member and wall structure on the second member into frictional engagement with the wall structure on the housing in response to a vertical load acting on the friction contacting surface on the cap. An apparatus, carried by the cap members, allow the cap members to horizontally slide relative to each other while limiting vertical separation of the cap members relative to each other during operation of the constant contact side bearing assembly.