2021 CHEVROLET COLORADO radiator

Chevrolet Colorado Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14430421) - 2021 - CRC - 2/10/20
248 Vehicle Care
3.6L V6 Engine
1. Coolant Surge Tank and Pressure Cap
2. Engine Cooling Fan (Out of View)
{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.
{Warning
Do not touch heater or radiator 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.
Engine Coolant
The cooling system in the vehicle is filled
with DEX-COOL engine coolant mixture. See
Recommended Fluids and Lubricants0321
and
Maintenance Schedule 0312.
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 0250.
What to Use
{Warning
Plain water, or other liquids such as
alcohol, can boil before the proper
coolant mixture will. With plain water or
(Continued)
Warning (Continued)
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.
.Protects against rust and corrosion.
.Will not damage aluminum parts.
.Helps keep the proper engine
temperature.
Caution
Do not use anything other than a mix of
DEX-COOL coolant that meets GM
Standard GMW3420 and clean, drinkable
water. Anything else can cause damage
to the engine cooling system and the
vehicle, which would not be covered by
the vehicle warranty.

Chevrolet Colorado Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14430421) - 2021 - CRC - 2/10/20
Vehicle Care 249
Never dispose of engine coolant by putting
it in the trash, or by pouring it on the
ground, or into sewers, streams or, bodies of
water. Have the coolant changed by an
authorized service center, familiar with legal
requirements regarding used coolant
disposal. This will help protect the
environment and your health.
Checking Coolant
The vehicle must be on a level surface when
checking the coolant level.
Check to see if coolant is visible in the
coolant surge tank. If the coolant inside the
coolant surge tank is boiling, do not do
anything else until it cools down.If coolant is visible but the coolant level is
not at or above the mark pointed to, add a
50/50 mixture of clean, drinkable water and
DEX-COOL coolant.
Be sure the cooling system is cool before
this is done.
If no coolant is visible in the coolant surge
tank, add coolant as follows:
How to Add Coolant to the Coolant
Surge Tank
{Warning
Spilling coolant on hot engine parts can
burn you. Coolant contains ethylene
glycol and it will burn if the engine parts
are hot enough.
{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.
{Warning
Steam and scalding liquids from a hot
cooling system are under pressure.
Turning the pressure cap, even a little,
can cause them to come out at high
speed and you could be burned. Never
turn the cap when the cooling system,
including the pressure cap, is hot. Wait
for the cooling system and pressure cap
to cool.
Caution
Failure to follow the specific coolant fill
procedure could cause the engine to
overheat and could cause system
damage. If coolant is not visible in the
surge tank, contact your dealer.
The coolant surge tank pressure cap can be
removed when the cooling system, including
the surge tank pressure cap and upper
radiator hose, is no longer hot.

Chevrolet Colorado Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14430421) - 2021 - CRC - 2/10/20
250 Vehicle Care
1. Turn the pressure cap slowlycounterclockwise. If a hiss is heard, wait
for that to stop. A hiss means there is
still some pressure left.
2. Keep turning the cap and remove it.
3. Fill the coolant surge tank with the proper mixture to the mark pointed to
on the front of the coolant surge tank. 4. With the coolant surge tank cap off,
start the engine and let it run until the
upper radiator hose starts getting hot.
Watch out for the engine cooling fan. By
this time, the coolant level inside the
coolant surge tank may be lower. If the
level is lower, add more of the proper
mixture to the coolant surge tank until
the level reaches the mark pointed to on
the front of the coolant surge tank.
5. Replace the cap tightly.
6. Verify coolant level after the engine is shut off and the coolant is cold.
If necessary, repeat coolant fill procedure
Steps 1–6.
Caution
If the pressure cap is not tightly installed,
coolant loss and engine damage may
occur. Be sure the cap is properly and
tightly secured.
Engine Overheating
The vehicle has an engine coolant
temperature gauge on the instrument
cluster to warn of engine overheating. See
Engine Coolant Temperature Gauge 084.
Caution
Do not run the engine if there is a leak
in the engine cooling system. This can
cause a loss of all coolant and can
damage the system and vehicle. Have
any leaks fixed right away.
If the decision is made not to lift the hood
when this warning appears, get service help
right away.
If the decision is made to lift the hood,
make sure the vehicle is parked on a level
surface.
Then check to see if the engine cooling fan
is running. If the engine is overheating, the
fan should be running. If it is not, do not
continue to run the engine and have the
vehicle serviced.
If Steam Is Coming from the Engine
Compartment
{Warning
Steam and scalding liquids from a hot
cooling system are under pressure.
Turning the pressure cap, even a little,
can cause them to come out at high (Continued)