Abstract: A railroad coupler knuckle includes a single, solid rib at a horizontal centerline of the knuckle that passes through a pivot pin hub thereof. The single, solid rib extends generally from a flag hole of a finger cavity of the knuckle to an opposite side of the knuckle from the flag hole. In another aspect, a railcar coupler knuckle includes a tail section, a hub section, and a nose section. The tail, hub, and nose sections define internal cavities including (i) a combined void that defines a pivot pin hub cavity and a kidney cavity and (ii) an isolated finger cavity. The combined void is formed using a first internal core during manufacturing of the coupler knuckle. The isolated finger cavity is formed using a second internal core during manufacturing of the coupler knuckle, such that molten alloy substantially separates the combined void and the isolated finger cavity.