This paper will describe the use of simulation at the US Army Tank-automotive and Armaments Command – Research, Development and Engineering Center (TARDEC) to investigate the vehicle stability, handling, yaw stability and ride quality of large military trucks. The multi-body modeling methodology used to create the vehicle models as well as the characteristic data used to define the models and their subsystems will be described. The criteria used to evaluate the dynamic stability characteristics, and the truck yaw stability / handling performance are identified. Also, the “virtual” tests performed in simulation to evaluate these performance characteristics are discussed. Efforts to improve the vehicle’s performance through an iterative modify-simulate-evaluate procedure, and experiments using the computer models designed to identify parameter modifications that have the greatest impact the vehicle’s yaw stability performance are also described. Design parameter trade-offs between lateral stability and yaw stability influences are identified as well as efforts to balance these trade-offs to arrive at an optimum configuration.