I have also heard that the early eco-boost motors could have problems. However my brother has a 2011 model with over 100,000 miles in all it's ever had was the spark plug change. If I was looking in 2011 and 2012 I would also consider the 5.0 as it is one hell of a motor it's just not near as torquey as the eco-boost.
My truck is a crew cab 4x4 slightly lifted on 34" 10 ply tires. It will hit 60 in 5.9 sec and that is at ~6700 lbs last time I scaled it. if I run 60-62 with the cruise set it will get 21-23 mpg. When I set cruise at 78 on the interstate it will get ~17.5. When towing, the fuel mileage isn't any better then a V-8. If the turbos are spooled up and building boost, your mileage is not going to be that great. But if you use cruise control when not towing and and keep the boost low, it will get great mileage. I've got over 100,000 miles and I did have an exhaust manifold leak that was replaced under warranty. Other than that it's been a fantastic truck and my next purchase will be another one.
This is the work trailer I pull around the southeast. I get 9 miles to the gallon pulling this trailer but as you can see it's about 10 feet tall and it's 8 1/2 feet wide.
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I've added the heavy springs to the rear and with the LT tires at 80psi it handles loads good. Not as good as my previous F250 but better than any half ton I've ever owned. With the stock springs, it was pretty soft and would sag under a heavy load and sway quite a bit on the highway. Just a $200 spring upgrade made a huge difference.
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