The forecasts about the behaviour of the Product Life Cycle (PLC) have been done by the Bass Model. The main contribution of this investigation is to propose the use of the clients assisted variable in the face of sales variable. Its main target is to analyze which variable is the most useful to calculate the stages of the PLC through Bass model, proposing a new way to manage marketing and sales departments in companies. In this investigation 223.557 clients assisted were analyzed nationwide by an automobile network dealer, 36.819 of them purchased cars during 24 months, which was the period of the study. In this analysis, the Bass model and non linear regression models were applied to define the stages of the product life cycle. The results show that we can get more consistent estimations of the product life cycle thanks to clients assisted variable. This study has theoretical and practical implications that can help enterprise management.