Diesel Exhaust Fluid - Chevrolet GMC Duramax 2023 Manual

If the infotainment display returns to the
previous screen, then one or more of the
necessary safety conditions has not been
met. If you cannot determine which
condition has not been met, see
www.gmupfitter.com to contact the GM
Upfitter Integration Group.
Continue to follow the instructions in the
DIC messages. Hold the exhaust brake
switch on the center stack below the climate
controls for more than three seconds, and
then release it, to begin the regeneration
process.
If the EXHAUST BRAKE ON message displays,
then the switch was released too soon.
Press it again to turn off the exhaust brake,
then try again when the DIC message
prompts.
When manual regeneration begins, the
engine speed increases, the engine cooling
fan sound increases, and a DIC message
indicates that cleaning is in progress.
A DIC message will display when cleaning is
complete. Cleaning could take up to
30 minutes. Upon completion, the engine
will return to normal idle, but exhaust
components will remain hot for several
minutes. Do not move the vehicle until the
exhaust has had time to cool. Manual
regeneration can be canceled at any time by
pressing the brake pedal or by turning the
engine off. Unusual noises may be heard if
regeneration is interrupted.

Diesel Exhaust Fluid

Warning
Avoid getting Diesel Exhaust Fluid (DEF)
on your skin or in your eyes as it could
cause irritation. For more safety,
handling, and storage information, see
the Diesel Exhaust Fluid container label.
Caution
Use only DEF that is GM approved,
or fluid containing the API certified or ISO
22241 label. The use of other fluids could
damage the system, requiring costly
repairs that will not be covered by the
vehicle warranty.
Driving and Operating
Caution
Do not mix fuel with DEF, and do not put
DEF in the fuel tank. This could lead to
costly repairs that might not be covered
by the vehicle warranty.
Diesel Exhaust Fluid (DEF) is used with diesel
engines to reduce the amount of regulated
emissions produced. Products such as AdBlue
are types of DEF. The fluid level in the DEF
tank must be maintained for the vehicle to
run properly. DEF is not a fuel additive. DEF
freezes when exposed to temperatures
below 11 °C (12 °F). For DEF tank capacity
see Capacities and Specifications 0 66.
It is normal to hear the DEF system purge
fluid back into the tank after the vehicle is
shut off.
Locating Diesel Exhaust Fluid
DEF can be purchased at your authorized
dealers. Additionally, some diesel truck
fueling stations or retailers may have DEF
for purchase. For vehicles with an active
OnStar or connected services plan, OnStar
can help to locate a DEF retailer. See
Customer Assistance Offices in the owner s
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