Recent years have seen a spurt in the demand for pick up trucks and sport utility vehicles (SUVs). Over a thirty percent jump in demand is expected in the next five years for the domestic and the transplant SUVs combined. The ratio of trucks to passenger cars on the road will be adversely affected in the near future by this growing demand. This shift of balance may compel an extension of CAFÉ to these classes of vehicles in the next few years.The differential carrier, one of the heaviest components in the drive train, is an excellent candidate for conversion into aluminum from iron. The potential weight saving is nearly fifty percent. The objective of this paper is to detail the successful development of an aluminum carrier to replace traditional ductile iron carriers.The paper highlights the design and developmental activities such as, comparison of alloys for conversion, design modifications to improve manufacturability, selection of casting process, pre-engineering, as well as manufacturing aspects of one typical differential carrier. Automotive designers are now convinced that the aluminum carriers meet the performance requirements and challenging demands of heavy duty drive trains of trucks, SUVs and sporty passenger cars, which are typically rear wheel drives.Opportunities exist for design modifications to improve manufacturability, reduce mass and cost. The paper identifies the scope for further improvements.