A lot of research has been done to improve the fatigue strength of materials by creating compressive residual stress field in their surface layers through the shot peening. In the present work, it is found that relaxed residual stress field varies with shot peening intensity and affects weight of EN 45A spring steel leaf springs. A stress approach model for weight reduction of leaf springs used in automotive vehicles has been experimentally developed simulating with industrial environment. Paper discusses a time saving and reliable method of predicting thickness and weight of leaf springs at various shot peening intensities for industrial applications. A model based on experimental results has been developed which predicts weight reduction of leaf springs for a given stress at varying shot peening conditions. (C) 2012 The Authors. Published by Elsevier Ltd. Selection and/or peer review under responsibility of American Applied Science Research Institute