As far as DEF mpg report....I've got 938 miles on my truck since last fill up, driving back and forth to work, driving around town on my day's off, according to the EVIC, (which has been within a tenth of correct) is showing 16.3 mpg...which, doing the exact same driving would have put the 10 or 12 trucks in the low 14's to upper 13', which would have been some city traffic driving and more than several stops and starts just like in the 13'....Truck is showing 3/4's of a tank of DEF left(if accurate) after a little over 938 miles on the truck....