Moving toward sustainable manufacturing has turned to an important debate between managers of any manufacturing organizations in order to keep in touch with the enormous competitiveness of the market. One important step to achieve this goal is to control the impact of their manufactured products toward three dimensions of sustainability (environment, economic and social). During the years, methodologies have been developed in order to assess the sustainability level of manufactured products. However, none of them focused on weighing their selected elements and sub elements using mathematical approaches. Consequently, lack of these weighting can have negative effects on precision of the assessment results. In this paper, a weighted fuzzy assessment method for product sustainability assessment was developed. Fuzzy analytical hierarchy process was used to weight selected elements and sub elements. Then, fuzzy logic was utilized to assess the product sustainability level based on acquired weights. Integrating fuzzy evaluation with weighted elements and sub elements and as a result, inclusive involvement with expert knowledge has made the proposed method more precise than the other existing methods. A case study of an automotive component was conducted to illustrate the efficiency of the developed method. Consequently, the results show that how a simple replacement in the product material can lead a manufacturer toward producing more sustainable products and achieving the ultimate goal of sustainable manufacturing.