Well,
Since I appear to have offended a few people here, I figured I'd go back and look up some real data...
You guys should check out TheDieselStop.com for info on guys driving 6.9 liter diesels of all sorts.
As you may choose to see, none of these Ford 6.9 liter diesel owners are claiming to get over 20 mpg under any driving conditions.
They all get around 18, at best.
Sorry, blame someone else, not my data.
As long as some people keep believing that big vehicles can get high mpg's when fully loaded then some people will believe anything.
I'd love to see a big truck get good mpg's it just aint happening.
