Didn't know we were discussing mileage. I've gotten as high as 14 on mine, and average 10 in town.
Update: Not sure when I last updated everyone, but we took our longest trip in Feb, to Florida and everything worked great. About a month ago we took another long one to NovaScotia by way of New Brunswick(Bay of Fundy-a must see) and Maine, returned thru New Hampshire with a great visit to Mt. Washington. NS is beautiful, as is NB and the other states. btw, do not patronize the Yogi Bear Campground in Sturbridge, Mass. Its a horrible place.
Big baby is going in for service next week, all of 18k miles, but it's time. I purchased brass tire valves for the duals, and the Chevy dealer will install them. Now I can check the tires without injury.