Hi Stacey - I ran into this recently on my trip to Charlotte in July. I was due for an oil change and DEF top-off, but I only had ~3000 mile since last oil change and DEF top-off. About an hour into my trip, the DEF Low alarm went off and profanity ensued. I knew I needed to stop and found a large diesel truck stop outside of Scranton which had one set of diesel pumps (for the big-boys) and another set gasoline and diesel pumps for cars & light duty trucks by the Welcome Center.
I drove down to the big-boy pumps (which advertised DEF at-the-pump) to find a
single LARGE diameter nozzle = I didn't see a 2nd small nozzle with a
blue handle for the DEF. Thinking maybe it was just the pump I stopped at, I walked over to a few other pumps and found every pump only had a single LARGE diameter nozzle.
Knowing that the LARGE diameter nozzle doesn't fit in our capless system, I couldn't use the big-boy pumps for:
I guess what surprised me is that the big boy pumps dispensed both diesel fuel and DEF
thru the same nozzle? This doesn't seem quite right to me as DEF is like 66% water and everyone knows that any sort of fuel and water don't mix. I would think this sort of dispensing would contaminate the small 5.5 gallon DEF tank in our trucks. Maybe someone who fills at-the-pump can chime in with their experiences...
After learning my lesson, I put my-tail-between-my-legs and skulked up to the Welcome Center to purchase a 2.5 gallon jug of DEF from the convenience store part of the complex. Filling my DEF tank from the 2.5 gallon jug was actually a lot easier than I thought it would be, and I was back on the road about a half hour later.
If you do plan to fill your DEF at-the-pump, you will need to find a service center with a separate DEF pump with a small diameter nozzle with a
blue handle to fit the filler-neck setup on our trucks. I did notice a new Mobil gas station recently built near me had dedicated DEF pumps with
blue handled nozzles.
Lesson Learned: Plan out where you are going to fill your DEF at-the-pump