I'm looking at buying a pretty nice Ecoboost, with one problem. It is geared 3.31 and my plans for it involve a lift with big tires and towing a good size trailer. Pretty sure 3.73 is the way to go. Should I keep looking for a truck that already has 3.73 or would it be worth it to change this one to 3.73? What would it take to change it as far as parts? Estimates on cost? The truck is a great deal, so I have some wiggle room to put into gearing, just not sure how much it is going to take. Thanks in advance.