The design of leaf spring has been a constant challenge for automotive and manufacturing engineers and it has undergone multiple revisions [2, 3 and 4]. The aim of this paper is to investigate and analyze how failure occurs on the semi-elliptical master leaf spring of a commercial car by analytical approach and using FEM simulation to ascertain the failure condition and to provide a cost-effective design modification for the same. The currently used 10 mm thick master leaf fails repeatedly at a particular zone close to the spring hanger end. After multiple trials for different thickness values and materials, recommendations were given for a better and modified design of the master leaf spring.