U not going able get good mpg with this.
Get 90's F150 with 300 6 cylinder with 5 speed 2wd plus 3.08 gear. I got 24 mpg on long highway at 65 mph but city it turd due 3.08 is highway gear.
And my old 1994 Explorer got 24 mpg out 4 speed auto with 4.0L OHV plus 3.73 on 300 miles highway. But average is 19-20 at 65 mph No cruise control.
3.0L you maybe not happy with power/gas.