So I am thinking of buying an ecodiesel and have found two decent deals on a 2014 SLT and a 2015 Big Horn. One has 118,000 and the other 112,000. Should I be concerned about the mileage? I heard that the ecodiesel has had some issues. I love the idea of the gas mileage and towing but just want to make sure before before I get rid of my F150