Customer satisfaction appears important not only in service companies, but in industry where product differentiation is increasingly difficult, too. The product is considered a global package “good & service”, services adding value to the product use. The study reveals information about measuring and monitoring business quality indicators in automotive industry. The case study has started from the decrease of the customers’ satisfaction. The quality indicators and their evolution over time were monitored. The input data were collected by direct observation, indicators and targets were set, and then the results were compared using different quality instruments. The purpose of this paper is to diagnose after-sale activity undertaken by a service unit through SIX SIGMA concept, Speci?cally this article will focus on the actions and activities of the service during the Warranty period when a customer purchases a new vehicle. A practical solution for scheduling the clients, documented in a procedure, followed by speci?c training and hiring technical staff has been set in place.