An aircraft bypass turbojet engine lubrication unit includes from three to five superposed pumps, a body housing the pumps and an internal passage in the body for communicating with each of the pumps. The material of the body exhibits a stack of layers in a direction of stacking, the pumps being housed in the said stack of layers. The passage exhibits an end in the direction of stacking of the layers and an internal profile, for example triangular, with two straight lines which form the said end and which are inclined with respect to the stacked layers. The lubrication unit may be manufactured by additive manufacturing in layers.