Operating Temperature; Winter Cover - Chevrolet 4500 HD 2023 Manual

Let the engine idle for 3 minutes before
shutting off the engine. This allows the
turbocharger to slow down while keeping
the bearings lubricated.
If the Vehicle Has Not Been Used for a Long
Period
If a diesel vehicle has been standing for an
extended period of time, the turbocharger
bearings should be pre-lubricated prior to
starting. See your authorized dealer for
more detailed information.
Before using a vehicle that has not been
driven for a long period, check the engine
and transmission for oil leakage, and make
sure the oil is at the required levels. If there
is insufficient oil, it will not adequately
reach and lubricate components, and a
breakdown will result.
Start the engine and allow it to idle for at
least five minutes. Check for abnormal
noises.
For instructions on warming up the engine,
refer to Starting the Engine previously in
this section.
If one year has passed since the diesel
exhaust fluid (DEF) in the DEF tank was
added, the DEF in the tank should be
replaced. Be careful not to inhale the
ammonia odor when replacing the DEF. Also,
please contact your nearest dealer about the
replacement work.

Operating Temperature

Recommendations for Warming Up the
Engine
The engine is sufficiently warmed up when
the needle of the engine coolant
temperature gauge starts to move.
Do not race the engine or quickly accelerate
before the engine has sufficiently warmed
up. Oil would not have adequately reached
and lubricated components, and a
breakdown may result.
The exhaust pipe becomes extremely hot
while the engine is idling. Before warming
up the engine, make sure there is no
flammable material, such as grass, waste
paper, oil, or old tires near the exhaust pipe.
Driving and Operating
Engine Warm-up System
During cold ambient conditions, the
automatic engine warm-up system operates
to reduce engine warm-up time during
idling.
Automatic Engine Warm-up : When the
engine is idling with the engine coolant
temperature below 62 °C (144 °F), the engine
warm-up system automatically closes the
exhaust brake and increases engine idle
speed so that the engine is warmed more
quickly. Warm-up is cancelled when the
accelerator pedal is pressed, and resumed
when the pedal is released. Warm-up is
automatically cancelled entirely after the
engine coolant temperature rises above
65 °C (149 °F).

Winter Cover

Do not cover the front of the radiator
with newspapers, cardboard or any other
flammable material to raise the engine
coolant temperature.
If you allow the engine to warm up but
the engine coolant temperature does not
rise, have the nearest dealer inspect the
thermostat.
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