Autonomous Vehicles (AVs) will revolutionize the way people travel by car. However, in order to deploy autonomous vehicles, effective testing techniques are required. The driving quality of an AV should definitely be considered when testing such systems. However, as in other complex systems, determining the outcome of a test in the driving quality on an AV can be extremely complex. To solve this issue, in this paper we explore the application of Quality-of-Service (QoS) aware metamorphic testing to test AVs modeled in MATLAB/Simulink, one of the predominant modeling tools in the market. We first defined a set of QoS measures applied to AVs by considering as input a recent study. With them, we define metamorphic relations. Lastly we assess the approach in an AV modeled in Simulink by using mutation testing. The results suggests that our approach is effective at detecting faults.