Chevrolet 4500HD Series 2019 Manual page 192

Any substance other than the
DEF may cause a breakdown to
the SCR system.
Use the DEF handling
equipment made of correct
materials (Polyethylene or
Stainless-steel).
Avoid contamination from using
dirty funnel for filling.
If a fluid other than the specified
DEF is mistakenly added,
incorrect fluid may cause a
failure. Have it inspected and
serviced at a dealer immediately.
Ammonia odor may be
generated when the DEF is
exposed to high temperature.
Do not add DEF above the F
position on the level gauge. DEF
may leak from the breather hose
while driving. Also, the sensor
may be broken when DEF
freezes.
Do not put your feet on or stand
on the DEF tank. The tank, pipe
or sensors may be damaged.
After stopping the engine, a flow
sound may be heard from the
DEF tank or DEF supply pump.
This sound occurs as the DEF in
the piping is returning to the
tank, and does not indicate an
abnormality.
See Winter Driving 0 151.
Adding DEF
1. Turn the engine control switch
to the ACC or LOCK position
and make sure to stop the
engine.
Driving and Operating
2. Wipe off dust or dirt from
around the filler port of the
DEF tank.
3. Turn and remove the filler cap.
4. Refill the tank up to the F
position in the level gauge on
the front face of the tank. The
DEF may overflow from the
filler port if it is added in excess
of the F position.
5. Tighten the cap after refilling is
completed.
6. Wipe off DEF that is spilled at
refilling.
Warning
On occasion, you may notice an
odor when the DEF tank is
opened. Do not sniff the filler
port, etc.
When refilling the DEF tank:
Failure to follow the above
instructions could result in a fire
or a breakdown of the selective
catalytic reduction (SCR) system.
191
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