The general public considers auto service operators to be experts in their work, and they use their advice and guidance when changing the oil. Therefore, due to the importance of this issue, during applied research conducted in a mixed (quantitative and qualitative) manner, an attempt was made to identify and prioritize factors affecting the offer of motor oil brands by Iranian auto services using the fuzzy Delphi technique. In terms of the research method, this research is considered descriptive survey research, and its statistical population includes all the operators of Iranian auto services. The statistical sample of the research consists of 36 Iranian auto service operators who were selected as a cluster from all over Iran. In the following, after collecting data through semi-structured interviews and questionnaires and analyzing the information, it was determined that the engine oil quality factor is the most important in introducing the engine oil brand by the auto services, according to the experts present. Also, after the quality of the engine oil, the two factors of matching the engine oil with the technical specifications of the car and the timely delivery of orders from the manufacturing companies were placed in the second and third ranks of importance, respectively.
