The elevation change may have also contributed to your mileage. What's Dallas, about 500' elevation or so? By the time you got to the rim of PD Canyon, you were at about 3600', and then when you left, you had to climb 800' just to get out of the canyon.
Everytime I drive to Dallas from Amarillo, I notice better mileage going than returning.
It was really nice meeting you & Terri over the weekend. Ya'll should come up more often, if only just for the better gas mileage.
