DEF - Usage

Keeping with the Snipe remarks, my 5er has a "Hot" water heater....

I checked with other Ram owners at work, and the general consensus is 500 to 700 miles to the gallon when towing. The Chevy guys report a little better.

As for the advantages of DEF, I only mentioned "Gas" mileage (input snipe here) in my earlier post. The DEF utilizing Rams also go twice as long between oil changes, with downside being the truck doesn't "make oil", so I'm now not recycling as much, and hence not doing my part for the environment. Fuel dilution due to Re-gen blow by and excess carbon build up from high EGR was fairly significant on my 2011.

cbshoestring wrote:
You would also be surprised how many people redundantly say "fluid" after using the term (initials) D.E.F. (Diesel Exhaust FLUID).

Ok...that was a snipe....I deserve troll status.

On a related note... VIN number. That is all.

I've said it more than once. FILL UP DEF AT A TRUCK STOP. Generally when my def is low I get a warning message to fill up in the next 1000 miles. CAN DO!!!! At the pump it goes for $2.78 a gallon. It is fresh (this stuff has a shelf life of 2 years max) No big deal, ever!

Wild Card wrote:

Dont really find it funny when someone gets a lesson on how things work. You really have no idea how many people buy these trucks and think that DEF fluid is used to clean the DPF in the regen process.

You would also be surprised how many people redundantly say "fluid" after using the term (initials) D.E.F. (Diesel Exhaust FLUID).

Ok...that was a snipe....I deserve troll status.

tinner12002 wrote:

Jhurk wrote:
Just on my maiden voyage with my 2014 Ram 3500 Diesel pulling 13,500lb 2009 Cardinal 34'. Pulls like a dream very nice to drive however after 1,000 miles I have gone through 1/2 tank of def, 2.5 gals. Normal,driving I was told I would get 5,000 miles to 5 gals of def. I know pulling under load you use a lot more but I was shocked when I looked at the guage? Is this normal? I'm going to the dealer to inquire and buy so,e more!

That's probably pretty close to what mine does when towing. Empty non towing it hardly uses any but yes, when towing they use a bit more. Normal usage in my opinion.

normal useage is around 1 gallon of DEF for 100 gallons of fuel. this is very close to what I use as well. so your useage seems on the high side, at 10mpg in 1,000 miles that is 100 gallons, so about 1 gallon of def. 2.5 gallons seems high. but the key is to track it accurately over say 5,000 or 10,000 miles.

Jhurk wrote:
Just on my maiden voyage with my 2014 Ram 3500 Diesel pulling 13,500lb 2009 Cardinal 34'. Pulls like a dream very nice to drive however after 1,000 miles I have gone through 1/2 tank of def, 2.5 gals. Normal,driving I was told I would get 5,000 miles to 5 gals of def. I know pulling under load you use a lot more but I was shocked when I looked at the guage? Is this normal? I'm going to the dealer to inquire and buy so,e more!

That's probably pretty close to what mine does when towing. Empty non towing it hardly uses any but yes, when towing they use a bit more. Normal usage in my opinion.

1jeep wrote:

N-Trouble wrote:

1jeep wrote:
I had an 08 diesel that didn't use DEF, it would inject fuel into the DPF, when that regen would happen your MPG turned into how many gallons per mile!

DEF trucks still inject diesel into the exhaust/DPF during regen. DEF is not a replacement for diesel being used during the regen process. Time to do a little homework on what DEF does and how its used.

No need I just get in and drive the truck, add stuff as needed.

BTW, I know it still uses fuel in the DPF, but I guess I should have reread my statement before posting to all these engineers up here...lol

Dont really find it funny when someone gets a lesson on how things work. You really have no idea how many people buy these trucks and think that DEF fluid is used to clean the DPF in the regen process.

You dont have to be an Engineer...you dont even have to be the head cashier at Walmart.

N-Trouble wrote:

1jeep wrote:
I had an 08 diesel that didn't use DEF, it would inject fuel into the DPF, when that regen would happen your MPG turned into how many gallons per mile!

DEF trucks still inject diesel into the exhaust/DPF during regen. DEF is not a replacement for diesel being used during the regen process. Time to do a little homework on what DEF does and how its used.

No need I just get in and drive the truck, add stuff as needed.

BTW, I know it still uses fuel in the DPF, but I guess I should have reread my statement before posting to all these engineers up here...lol

The DEF is only to reduce NOX emissions. Pre DEF systems did this by delaying injection to reduce peak pressures, and pumping a lot of exhaust back into the engine with the EGR. The DEF and SCR allow lower EGR flows, and more advanced timing, which puts the peak pressure where it makes more power, not less NOX. The DEF system then treats the exhaust to break down most of the NOX, to be below EPS levels. Advancing timing also helps with soot production, as the fuel has longer to burn in high temp / high pressure of the engine, before being shot out into the relatively low pressure exhaust system. Remember, more power for the same fuel is the same as less fuel for the same power.

DEF allows the engine to run hotter and produce less particulates. The downside of this is increased NOx which is handled by the DEF after treatment. Since less particulates are being collected in the DPF, regens are less often with a DEF equipped engine.