Deep rolling is a method of cold work deformation and burnishing of internal combustion enginecrankshaftjournalfillets to increase durability and design safety factors. Compressive residual stresses can be measured below the surface of a deep-rolled fillet. Other types of fillets on shafts or tubes can also benefit from this method. Cast iron crankshafts will experience the most improvement potentially doubling their fatigue life. Typically the crankshaft is machined with under-cut fillets as opposed to tangential radiused for ease of manufacture, although all types can be deep-rolled. Most automakers are currently utilizing this technology including: GM, Ford, and Chrysler engines. Hegenscheidt-MFD Corporation, the French SPMS SUPRAMATIC brand, and ICM (teamed with Lonero Tooling) are the only major machine/tooling manufacturers of this application in Europe and North America, supplying a highly specialised product throughout the global manufacturing sectors.