I just purchased a set of Michelin MXV 4. The original tires lasted 32K. I was averaging 53mpg with my old tires. Since I installed the Michelins, the ride is exceptionally smooth and much quieter then the factory rubber. The mpg however dropped to 47-49mpg. That's a pretty good hit. I love the ride and quiet but I never expected the loss of mpg. I am thinking of pumping these bad boys to 40psi and see if that helps. Your thoughts?
I replaced my stock 16" wheels with 17" Motegi hoops and the MXV4's, I'm running mine at 40 rear and 42 front, I don't really track the mileage hard core, just go by the displayed MPG #, feels like I might have lost a mile or two, nothing major at all. I'm not a hypermileing driver, I average right at 45mpg tank after tank, pretty much the same as the stock wheel setup. I'm very happy with these tires, much better handling and all the wallowing around in windy conditions is gone. Not sure this helps you...just my experience.
You should read the fuel economy section more often. http://priuschat.com/forums/gen-iii...614-my-mpg-results-three-different-tires.html The MXV4 is not really a LRR tire and everyone that purchases them drops mpg over the OE tire. They are good tires but not good for fuel efficiency. For better than OE tire fuel efficiency you should look into the Energy Saver A/S, Ecopia EP100 and dB Super E-Spec.
The Michelin energy saver A/S was not available so I got the similar, but not LRR Harmony. My fuel economy has dropped some but Michelin claims that the Harmony is an 80,000 mile tire compared to the energy saver A/S 60,000 for the same price. If it does last 80,000 miles I'll probably be in a nursing home by then.
