Jumpin' Jehoshaphat ! If it's a stock slant 6 and at 14.7, I'd be look'n into that before I even thought of leaving. Ouch to that!! Even at 70 mph, I'd think 20 + would be more than reasonable to get. We got 17 mpg with a '70 dodge truck with a 340 and mild cam at 65 mph on a 2000 mile trip back in the late 90's. Thermoquad and 2.76's.
