Do you seriously want to ruin your engine by breaking the rules every now and then? Your gas tank says supreme unleaded fuel only. there is a reason why they tell you 'only'. I am not trying to be a smart a$$ here, but I have seen this question many times and I drive an Infiniti G35 coupe that requires premium gas only and I dread having to pay for the premium unleaded gasoline, but I use it because I bought myself a high performance car. Being in San Francisco with many hills and stop lights, my gas doesn't go a very long way and the $4 prices for supreme that will hit me in the summertime will not help me either. Your engine was designed to use a higher octane gasoline, so you should use it. Other cars, such as hondas and toyotas are designed to run on regular gas only, but people believe that buying a higher octane will give them better performance. not true.Why risk the chance of ruining such a nice SUV as yours? Stick with premium unleaded.Hope this helps.