I would experiment with different grades, and see what kind of mileage you get. I have always run midgrade (87 here) and it has worked fine. 85 gives me all sorts of knocking and pinging. The last time I filled up, I was in a hurry and pulled up to a pump that had only premium and regular. So, I just filled up with premium for an experiment. I keep track of mileage on every tank of fuel, so when I filled up the next time, I compared the premium gas mileage to the regular. I got an extra 20 miles or so on the premium, so it was worth the extra 2.00 it cost at the pump, at 18mpg. So, the switch may not be benificial if you get lower mpg. <img src="/forums/images/graemlins/cheers.gif" alt="" />