Community Forums

luvlabs · 06-22-2017, 10:42 AM

I think the current estimate is about 6 gallons. There must be an official number somewhere but that seems about right.

Hooligan · 06-22-2017, 01:50 PM

Sprinter cut-away chassis, with the V-6 diesel engine- (Sprinter, Navion, View etc) has a 4.7 gallon DEF tank. Mercedes estimates 1720 miles per gallon of DEF. Seems fairly close to my results (1650+) over the 23K miles on my 2016. Again it depends on driving style and conditions..

MtnTrek · 06-22-2017, 05:40 PM

Quote:

Originally Posted by Hooligan

Sprinter cut-away chassis, with the V-6 diesel engine- (Sprinter, Navion, View etc) has a 4.7 gallon DEF tank. Mercedes estimates 1720 miles per gallon of DEF. Seems fairly close to my results (1650+) over the 23K miles on my 2016. Again it depends on driving style and conditions..

With those same records/logs estimate fuel consumed for those 23K mi. I'd expect the DEF to overall fuel consumed to be approx 2-3%?

Camper Ken · 06-25-2017, 08:41 PM

As "Hooligan" posted, I also had about 1700 miles when I added a gallon of DEF to top it off. My plan is to add a gallon about that often to avoid some problems associated with running it so low you get the warning light.

Camper Ken · 06-25-2017, 08:48 PM

Quote:

Originally Posted by TexasSprinter

We just did a 4700 mile trip without adding DEF once. I tested once and was running about a liter every 600 miles. That seemed high so I took it to MB dealer. They tested, calibrated, tested some more, and said my usage was 'normal'. So I've not quite figured it out yet. I'm a little leery of the "wait until you get the message" method, but the dealer swears that is better than continually topping it off.

I was told the exact opposite. The dealer said keep it topped off to avoid running it so low to expose the sensor in the tank. Even though DEF is available on the road, I don't want to be looking for it while traveling. DEF is also sensitive to long term storage in high temps so I prefer not to carry it with me.

MtnTrek · 06-25-2017, 10:53 PM

Quote:

Originally Posted by Camper Ken

DEF is also sensitive to long term storage in high temps so I prefer not to carry it with me.

No, it's direct sunlight (UV) DEF is not stable with. Would you suppose the folks in AZ's 120 heat drain it out and replace it with a fresh pint from the north side of the ice box every other day? They mount those reservoirs in spots that are warm / hot to thaw them out in sub freezing weather.
Obviously if it makes you feel better add it a pint at a time, do that.
Many modern day fluid sensors are not even exposed to the fluid they sense.

Keep the shiny side up.

Camper Ken · 06-26-2017, 11:48 PM

Quote:

Originally Posted by MtnTrek

No, it's direct sunlight (UV) DEF is not stable with. Would you suppose the folks in AZ's 120 heat drain it out and replace it with a fresh pint from the north side of the ice box every other day? They mount those reservoirs in spots that are warm / hot to thaw them out in sub freezing weather.
Obviously if it makes you feel better add it a pint at a time, do that.
Many modern day fluid sensors are not even exposed to the fluid they sense.

Keep the shiny side up.

Thanks for setting me straight on all this. Certainly makes sense. I was repeating what I'd read on forums like this.

MtnTrek · 06-27-2017, 03:21 PM

No worries my friend.

We should all check our facts the best we can from time to time. There's definitely wonderful merit to these forums and opinions being expressed. It seems the biggest issue in this information era is so much data. The trick is managing to make sense of it all.

Keep it between the ditches.