My 04 EB 2x2 with 5.4L 2V 3.73 gears, gets 8-9.5 around town and 17-18 hwy.
If I drive around town like I have an egg on the accelerator, it MAY get close to 10.5.
I don't get Ford in this area. This mildly tuned engine should get much better econ.
I had a 2001 Suburban 4x4 GMT800, 3.73 gears, LS1 5.7L 350HP engine. At that HP the engine is obviously tuned more radically and is larger, but it got MUCH better fuel econ than this Expy ... 14-15 city 18-19 hwy, driven normally and measured by hand, regular as clockwork. That Sub was heavier than my Expy.
I've gone over the Expy, monitoring params whilst driving, and I don't see anything that would cause this terrible mileage. I'd seen people complain forever about the Expy's mileage, so it is what it is, I suppose.
Wish it had a diesel. My GMC 3500 SRW Duramax gets 15city, 20hwy (no trailer) so think what the Expy could get... not to mention that it'd be unbeatable in a drag race.