filled up yesterday after first tank after dealer, 636miles total, tank was topoff, ran 377miles @ 18.17gals=20.7mpg, truck said i used 20.7gals total=18.2.
I run 56 miles, mostly hwy miles to and from work @70mph about 15 city to get out @ 35mph. A lot better them my 04 cc 4x HD 6.0