This paper will discuss how proven automotive systems engineering lightweighting principles and practices are being adapted and applied to combat and tactical ground vehicle systems. An automotive lightweighting methodology has most recently been utilized to reduce the weight of a light-duty pickup truck by 511 kilograms resulting in a 20.8% vehicle mass reduction. A holistic approach to light-weighting offers great benefits with additional mass reduction at a cost savings, reducing the overall vehicle lightweighting cost impact. Automotive studies have shown additional vehicle mass-reductions in the range of 3-5% are achievable when vehicles are aggressively light-weighted (i.e., approximate 20% vehicle mass reduction range). Although many factors like customer usage, function and performance requirements, production volumes, product life cycles, value stream, manufacturing infrastructure, litigation application, etc., are indeed considerably different between automotive and military, these differences do not significantly alter the fundamentals of a robust systems engineering approach to lightweighting.