The WCM philosophy foresees, basically, the reduction of losses and waste through the elimination of stages that do not add value to the process, providing the company with greater production speed and competitive advantage. The company that is the object of this study is a heavy equipment assembler that has in its product catalog the hydraulic excavator. The company faces several problems related to the labor force in the assembly line of this equipment, defects caused by lack of training, lack of attention from employees, forgetfulness and lack of motivation are some of the factors that affect costs, production time and product quality. This work aims to describe the implementation, in an innovative way, of the Quality Gate quality tool, in order to identify, control and reduce the failure rate found in the assembly line of the hydraulic excavator. To this end, the concepts and techniques of world classmanufacturing (WCM) were applied, together with a treatment flow for the respective defects. The results of the research show that Quality Gate is a tool that is simple to implement and promising in terms of the desired results.