One of the main trends in diesel engine technology is the reduction and control of lubricant consumption, since the lube oil constitutes a major contributor to the particulates exhaust gas emissions. Many efforts have been recently dedicated to the development of oil consumption simulation tools. This paper presents a methodology based on piston and ring dynamics simulation, coupled with an additional code that simulates the engine oil consumption. An example of the procedure is shown for a typical DI diesel engine, where some piston design parameters influence are studied. Finally, some engine tests results are presented in order to validate the numerical prediction.