The automotive industry faces many competitive challenges including weight and cost reduction to meet CAFE standards. In particular, a thin door panel optimized for weight reduction can cause high manufacturer warranties and durability problems. Traditionally, the assessment of door slam durability is accomplished by tests rather than using computer aided techniques. Many simple CAE techniques such as simple linear static and dynamic analyses have been used to evaluate the door structural integrity. However, the door slam event requires complex analysis due to the transient impact phenomenon. To solve this complex door slam event with a computer based technique is a challenging and interesting problem for CAE engineers. However, a simplified technique has been developed to anticipate the potential durability problem in the door. This technique involves the use of the computer- based finite element method incorporating inertia relief and fatigue life prediction. Actual testing validated the analytically predicted results. This method provides an inexpensive way of predicting door slam durability reducing development time and product cost. As a result, the new approach aided the door design robustness.