Just completed a 1495 mile vacation( NH - VA and back )in my 2011 Patriot 2.4L CVT FDI. My overall average was 30.18 MPG for the trip( well the highway to and back portion - not counting in city while there ). Best tank was 34.2 and worst was 28.09. Very happy with the results.
A point to make seeing as this thread is about MPG @ 75MPH+...
I kept the vehicle at a reasonable speed and it paid off with MPG well above the EPA rating of the vehicle. No way I see those same #'s if I went 75MPH+. I might have seen 24-25 MPG tops. I set my CC at 62 MPH in the 65 MPH zone as it seems to be the best compromise for this vehicle between speed and MPG. If the posted limit was lower I went 5 MPH over unless it was a work zone( LOTS of those )where I stuck to the max limit.
One way the trip distance was 659 miles. So basically 10 1/2 hours of driving @ 62 MPH. If I floored it and went 75 MPH like the OP talks of it would have taken 8 3/4 Hours. Just not worth it, for me, to lose the MPG and risk a ticket to gain an hour and a half. When you are talking the shorter distances we all drive in our normal day to day affairs the time savings is minimal at best.
2014 Jeep Cherokee
3.2L Pentastar V6
Active Drive I