First half-tank that I hand-measured was 9. That was on the lift and stock tires. Currently running through the first complete full tank of lift and tires.
I have been using it for putting around- not a whole lot of highway driving. Even when I have driven it to work, my commute consists of highway driving that is almost always pretty busy (not quite stop-and-go, but almost). I expect closer to 11-12 once I can get it on the highway at 65 for a few hours.
I let my brother in law use it for a few days. I'm excited to get it back and take some interior dimensions in the rear so I can CAD up a rear platform. I use Catia and Creo extensively at work, so that will be no problem. It will be a problem to work around the huge spare tire that will live in the stock spot until I feel like springing for a rear bumper with tire carrier.
Also going to be ordering an '05 grill to freshen up the front a bit.
Taking it on a short camping trip with some friends in 1.5 weeks. Would like to flush the coolant, change the oil, and replace plugs before then.
Nice! Not as bad as I had figured. When I was in the Navy I had an F350 dually 4x4 with the V10 and it only got about 7 or 8 on stock tires, but the truck wasnt exactly driven "lightly" if you know what I mean. I had to tow a 42ft enclosed 5th wheel weighing in around 23K lbs, and the V10 did ok, but returned me about 4 or 5 mpg.
And I am SUB'D to this one!