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
ktmrfs wrote:
two ways
1) my truck gives an initial warning at 30% which even worst case is at least 1,000 miles. Then it continues to count down and give warnings. If I'm dumb enough to ignore the gauge for 1,000 miles I get what I deserve.
2) DEF usage is about 1 gallon of DEF for 100 gallons of diesel. pretty easy to keep track of in my head.
3) If I'm traveling, before I leave I can have a pretty good idea based on last fill how many miles I can go before the 30% warning comes on. If I think I will be close, easy enough to put a 2.5gallon jug in the bed.
You need to keep that LML. #1 I've never seen a warning of more than 300 miles. And the mileage given isn't right, it's short 20-25%. And #2 the L5P sucks DEF. The one time I kept track of the fuel for a whole tank of DEF worked out to about 1 gal DEF to 45 gal diesel. That's twice the rate of the LML.
