Good afternoon,
I have a 2016 F-150 XL with 245/70/17 tires, I am considering going to a 265/70/17. What issues might I incur?

 

Being wider, sufficient clearances would come to mind. Maybe(?) a slight increase in tire wear in the center of the tire but that remains to be seen.

 

A lot of times when we go to a wider tire when the steering wheel is turned to either extreme end the tire now makes contact with the inner part of the vehicle

Sometimes we can't see this until the wider tire is installed. You might check just how much clearance there is when your present tire is turned to the extreme position.