A method of manufacturing a pump assembly includes sand casting a pump housing with a cavity and die casting an impeller that includes pump blades and a first portion of a shroud. The pump housing may be sand cast as a one-piece component and the impeller may be die cast as another one-piece component. A pump cover is provided with a second portion of the shroud. The pump cover is inserted into the cavity so that the second portion of the shroud is adjacent to the first portion of the shroud, providing a substantially continuous surface defining flow channels through the impeller. A pump assembly manufactured according to the method is also provided.