This is an image of the assembled front truck. Note the bracing is in a U shape over the front axle, which is clearance for the sprung draft gear the locos were equipped with. Also note the forged frame around and above the bolster. The locomotive did not contact the bolster pads directly on the front truck, it rode on the forged frame (called an equalizer by WISCO) that allowed the truck to roll under the loco frame on uneven track. The loco rolled with the movement of the center truck however, which had hard bolster pads to contact the frame.