Gas or diesel?
Towing you can expect 9-10mpg at best with either
City driving, 14mpg at best with Gas maybe a touch better with diesel
Highway, 75mph cruise about 16.5 gas and 18/19 diesel maybe a touch better depending on road conditions.
Come over to the XD forumns and get better info. I know what my ProX4 is getting, not much difference between 2wd and 4wd.