Much research has been carried out to improve the fatigue strength of materials in general and leaf springs in particular by creating a compressive residual stress field of their surface layers through shot peening. The phenomenon of surface roughness is important when considering contact between metallic bodies. The effect of shot flowrate on surface roughness was identified. Full-scale laboratory testing of EN45A spring steel leaf springs was carried out using an electrohydraulic testing system to show the extent of improvement in fatigue life due to shot peening. Double shot peening was performed on leaf springs and its effects on surface roughness, compressive residual stress field, and fretting fatigue were noted. The surface roughness model is in accordance with the experimental results.