Abstract: An apparatus is provided to supply oil to a differential bearing mounted between relatively rotating concentric shafts, for example, inside a gas turbine engine. In one form, the apparatus includes a fixed nozzle that injects oil into an annular collector dam mounted on the outer floating shaft. The dam construction utilizes centrifugal force to cause the oil to flow forward through passages into an interior area of the outer shaft. Inside such shaft, the oil is directed by dispensers into an oil transfer tube that traverses the distance inside the shaft from the dispensers to the bearing. The inside wall of the tube is flared to a larger diameter at the forward end, and the centrifugal force resulting from shaft rotation forces the oil forward into the bearing. At the forward end, the transfer tube contacts the outer race of the bearing thereby lubricating the bearing throughout a 360 degree surface area.