Why in the hell are you still paying $3.15 per gallon ($47/14.9)? Where do you live, Rip-off City? Here's-My-Wallet-Help-Yourself-ville? The national average is only $2.34, and a lot less than that in many places. Or did you figure you're MPG wrong?
And no, the X is NOT a high MPG vehicle! If you think there's something wrong with your truck, that's a different question. However unlikely - you posted this as a gas rant. 14.9MPG is not that far off from "average" (it will depend on how you define "average" for these trucks with various extras - tires, lifts, etc.).
-G-