DEF Math
The owner's manual says my truck has a 5.5 gal DEF tank. I waited until I was down to 1/4 on the gauge, just above the red zone, and added a 2.5 gal box of Blue DEF from Advance Auto. Now the gauge ...
Forum Discussion
I think it's beyond dumb to not have a DEF gauge, or at least a way to check the level in the EVIC. Anytime I'm leaving for a longer trip I like to have my DEF tank topped off so I don't have to screw around with it until I get back home. A warning at 30% at the beginning of a trip is something I would have to deal with while on said trip.
