[C-ya]

The one and only warning I got from the DEF system was 100 miles until no start. I had owned the vehicle for about 10 months at that point and had driven about 5K miles. I topped the tank off within a few days of purchase so I would have a baseline. Weird that I got no other warnings.

 

[C-ya]

For what it's worth, I have never added without being prompted by the system in my 4 years of ownership.

I have eschewed that approach since I was only given "100 miles". I top off twice a year.