4 mi / kWh is normal for you? What's your ambient temp, driving conditions, and terrain like? Cause I have suburban hilly areas with 60 mph freeway at 50F to 60F temps with off/on rain and get average 3.6 mi / kWh, HVAC set to 70F ECO just on defogger, recirc on, fan on 2nd from lowest, and heated steering wheel on.
In the summer with 70F to 85F, no rain, same commute, I get average 4.15 mi / kWh, HVAC set to "65" blowing just on me, recirc on, and fan at 2/3s. I am impressed you get near 5.