The invention relates to a railway car truck incorporating an interconnection between a side frame and a bearing adapter. The bearing adapter may receive a reduced coefficient of friction surface member in a recess on a top surface of the bearing adapter, facilitating a reduced lateral spring rate of the wheelset. Alternatively, or in combination, an adapter plate is received in the pedestal jaw on the bearing adapter to retain the reduced coefficient of friction surface member above or below the adapter plate. The adapter plate may be provided with surfaces about perpendicular to the longitudinal and lateral axes of the side frame to support elastomeric members, which may provide different longitudinal and lateral spring rates in response to a load applied to the truck.