Here's a real life comparison....
I bought a wake boat 18 months ago. An Axis A-22, trailer and boat weight over 5000lbs. Bought a 2011 Ecoboost F-150. The engine had no issues pulling the boat through rolling hills; 5 to 6% grades. The rear springs sagged when the trailer was attached. I added airlift air bags to fix that issue. Wife leaves, we get divorced, she took the truck. I buy a 2012 Chevy 1500 with the the v-8. Chevy pulls the same boat with ease. The Chevy is not sagging like the F150 did, so I don't need the air bags. The Chevy gets better fuel economy in almost all driving situations. The Ecoboost was 1 mpg better driving at 65 mph with an empty truck. Other than that, the Chevy gets better economy. Both are nice trucks, the Chevy seats feel more comfortable to me. Real life fuel economy, I am not heavy footed, I am usually the last guy off the line at a stop light and I rarely speed.
Before someone thinks that I am a biased Chevy owner, let me say that as a contractor that drives a 1 ton service truck 30,000 miles a year, I prefer the F350 (had 3) to the Chevy 3500 (have 1); going back to the F350 when I trade later this year. Had a 2000 Dodge Ram, won't ever buy another Dodge truck.