Looking at your information I can't understand why the automatics don't get better fuel Mileage than they do, to put it into perspective I just returned home from a vacation in Hilton Head. On I-95 there were stretches that I maintained 80 mph for up to three hours solid and the tachometer steady on 3500rpm with my 5 speed. A full 750 rpm higher than your auto and still returned 31.7 mpg. but what I wouldn't give for a taller 5th gear and a lower rpm. The engine drone at that speed is a little annoying after 8 hours of driving.