My diesel now has 870 miles on it. 460 of those miles were driven today. At highway speeds of 70 to 80 the mileage ranged from 28.2 to 31.2. I was pleased. Before the drive I checked the diesel exhaust fluid. The "wheel" in the center display showed it about half full. I added a 2.5 gallon container and the "wheel" showed full. That was the last time I was able to access the "wheel" to show me the remaining fluid. It ain't there. I checked the owners manual. It does not reference diesel exhaust fluid anywhere except to say "for those vehicles equipped" there is a gauge. I will search online to determine the consumption rate but the disappearing display should show that. Dealership closed. Something here is definitely goofed up.