Just purchased new 2017 Expedition XLT. Can I use 4A to drive all the time except off road ?

 

Welcome to FTE! Yes, you can use 4A all the time; it is like the "AWD" on many SUV's and cars that kicks in when you need it but won't cause drivetrain "windup" like the 4H or 4L settings which should not be used unless you are totally on loose or slippery surfaces.

On dry roads in the summer, or on dry-road long trips, 2H *might* get you a bit better MPG.

Happy New Year. I have been really tempted by the great deals on 2017 Expeditions and prefer the XLT, but have avoided buying one so far
George