2010 Ford Ranger 4.0L gas; kept first 4 yrs of fill-ups on phone app. Overall average including winter, summer, city, highway, 4x4, winter starts and idling was(is) .... 20L/100km. Window sticker said 11.x/100km highway, 15.x/100km city. Worst was one winter week with mostly 4x4, that put me in the 33L/100km range. This average was not particularity lead footed, but not eggshell on gas pedal either as it was used as a utility service vehicle and had time constraints to meet. Also tools and equipment added about 500 lbs and a ladder rack with 2 ladders sticking out on top made me as un-aerodynamic as could be.
One winter morning I left Regina headed to LaRonge. Distance is 600km but throwing in fuel stops and eats, its about 7-8 hrs. Should have made it to Prince Abert (~350km), except it was -35c going straight into a very very stiff wind. Made it to Melfort (280km) with my cabin heater putting out less and less heat, where I put 72L into a 65L tank! The fuel stop out of the wind allowed the vehicle to defrost a bit and the cabin heater regained its ability to heat normally. At the end of a week, they asked me to return to Regina at 3:30 pm; sundown was sometime around 4:30. Having been scared once, I told them they better get me a room for another night as I wasn't going to travel alone at night in the bitter cold on a road that normally has light traffic, and even less traffic in the cold, and very little cell reception for the first 200km. They were super pi**ed as they had me booked in Regina for the next day already.
Just jealous hearing that you can get 14L/100km when to get anywhere near that I would need to be going downhill with a stiff wind behind me.