Try to use "Car" diesel. It's B5-B10. Truck stop diesel can be up to B20. You'll get better mileage with the B10 in the smaller diesels (under 10 liter) IMHO. The big truck 13 liters, etc... don't seem to mind the B20. (I drive both.)
You will hardly use any DEF in everyday driving.... When towing you will use a lot more.
Def is Highly corrosive make sure rinse off any overspill.
Make sure you keep the red plug in the diesel filler when adding def. You can over fill the def before you know it. Def tank is about 6 gals but I could only get about 2 gals in it when the gage read 1/2.
Did you get 2wd or 4wd?
2016 FR Vengeance 25V Toy Hauler
2015 Ram 2500HD CC 4x4 6.7L Cummins
2004 Kawasaki Vulcan 2000
2005 Troy Built 3500/5250 Genny