Cooling System - GMC Sierra 2500 HD 2023 Owner's Manual

Caution
If the air cleaner/filter is off, dirt can
easily get into the engine, which could
damage it. Always have the air
cleaner/filter in place when driving.

Cooling System

If the vehicle has the Duramax diesel
engine, see the Duramax diesel supplement.
The cooling system allows the engine to
maintain the correct working temperature.
Warning
An underhood electric fan can start up
even when the engine is not running and
can cause injury. Keep hands, clothing,
and tools away from any underhood
electric fan.
1. Engine Cooling Fan (Out of View)
2. Coolant Surge Tank and Pressure Cap
Warning
Do not touch heater, radiator, a/c pipes
or hoses, or other engine parts. They can
be very hot and can burn you. Do not
run the engine if there is a leak; all
coolant could leak out. That could cause
an engine fire and can burn you. Fix any
leak before driving the vehicle.
Vehicle Care
Engine Coolant
The cooling system in the vehicle is filled
with DEX-COOL engine coolant. This coolant
is designed to remain in the vehicle for
5 years or 240 000 km (150,000 mi),
whichever occurs first.
The following explains the cooling system
and how to check and add coolant when it
is low. If there is a problem with engine
overheating, see Engine Overheating 0 313.
What to Use
Warning
Plain water, or other liquids such as
alcohol, can boil before the proper
coolant mixture will. With plain water or
the wrong mixture, the engine could get
too hot but there would not be an
overheat warning. The engine could catch
fire and you or others could be burned.
Use a 50/50 mixture of clean, drinkable
water and DEX-COOL coolant. This mixture:
Gives freezing protection down to 37 °C
( 34 °F), outside temperature.
Gives boiling protection up to 129 °C
(265 °F), engine temperature.
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