One of the major applications for cold formed carbon steel 'C' sections is through load carrying structural frame side members in heavy road vehicles. Though it is expected that forming operations would enhance the mechanical properties of sections as a whole by strain-hardening, it leaves certain amount of residual stresses throughout the sections. It is thus necessary to account for the effect of residual stresses remaining from cold forming operations accurately, while assessing the mechanical behavior of truck side frame rail sections. In this work, an experimental investigation was carried out to assess residual stresses induced by cold forming operation of truck frame rail sections through X-ray diffraction method. Also an attempt was made to study the effect of shot-peening operation employed as a surface enhancement method on frame rail residual stresses. © (2012) Trans Tech Publications, Switzerland.