This paper describes the methods employed to attain very low vehicle tare weight in the development of a new line of high entry tilt cab highway tractors. Design criteria mandated no sacrifice in durability or reliability, and substantial improvements in driver space, ride, noise level and aerodynamic drag as compared to the old model. The methods used to define and organize the Engineering program are covered as well as the design and test methods employed. Specific examples are provided to illustrate the design, use of computer aided engineering such as finite element analysis and life prediction, as well as the use of accelerated testing procedures. Finally, the production vehicle is compared to the targets and to competition at introduction time where it placed lightest weight in its class.