I just got my first def message since the hot tune was flashed back in June. My Def gauge shows 1/4 till empty and the message came up today. 700 miles until engine won't restart. I've emailed Green Diesel on this but has anyone else had there gauge not go any lower than 1/4? It's been a very long time since I've added Def. Like sometime early last March. Anyone go down to zero miles until restart? Keith replied to my email and said everything will be fine and the truck will restart at zero. Just wondering how long anyone pushed it.