Have the same truck and average 10.4 mpg on shot trips in town. Just got back from a 300 mi trip in Vt almost all highway @ 70mph on cruise and averaged 15 on the lie o-meter. We have some long mile plus hill grades and the truck only downshifted twice to 5th. The rest of the time 6th and never dropped out of lock-up. The other thing was even on the pull up the hills the speed stayed locked @ 70. The needle never wavered. Every other vehicle I have driven has had a 4-5 mph drop before it would down shift. I'm impressed. Love my trk.