I don't refill DEF till it's almost out. We were on a trip, my turn to drive out in morning. There was a red icon on the dash that looked like fire. Checked the RAM owners manual to see what this icon meant--nothing. Manual gives so much other BS but nothing on what these pictures mean. I saw the DEF gauge and noticed the DEF had gone past the white line into the red line. Now I know what the red fire icon means.
2016 RAM 2500 4X4 Mega cab