Diesel Exhaust Fluid - Dodge 2015 RAM Owner's Manual

3. Stop filling the DEF tank immediately when any of the
following happen: DEF stops flowing from the fill
bottle into the DEF tank, DEF splashes out the filler
neck, or a DEF pump nozzle automatically shuts off.
4. Reinstall cap onto DEF tank.
Filling The Def Tank In Cold Climates
Since DEF will begin to freeze at 12°F (-11°C), your vehicle is
equipped with an automatic DEF heating system. This
allows the DEF injection system to operate properly at
temperatures below 12°F (-11°C). If your vehicle is not in
operation for an extended period of time with temperatures
below 12°F (-11°C), the DEF in the tank may freeze. If the
tank is overfilled and freezes, it could be damaged. There-
fore, do not overfill the DEF tank.
Extra care should be taken when filling with portable
containers to avoid overfilling. Note the level of the DEF
gauge in your instrument cluster. On pickup applications,
you may safely add a maximum of 2 gallons of DEF from
portable containers when your DEF gauge is reading ½ full.
On Chassis Cab applications a maximum of 2 gallons may
be added when the DEF gauge is reading ¾ full.

DIESEL EXHAUST FLUID

Your vehicle is equipped with a Selective Catalytic Re-
duction system to meet the very stringent diesel emis-
sions standards required by the Environmental Protec-
tion Agency.
The purpose of the SCR system is to reduce levels of NOx
(oxides of nitrogen emitted from engines) that are harm-
ful to our health and the environment to a near-zero level.
Small quantities of Diesel Exhaust Fluid (DEF) is injected
into the exhaust upstream of a catalyst where, when
vaporized, it converts smog-forming nitrogen oxides
(NOx) into harmless nitrogen (N2) and water vapor
(H2O), two natural components of the air we breathe.
STARTING AND OPERATING 267
4