radiator cap GMC TERRAIN 2020 Owner's Manual

Page 294 of 425

GMC Terrain/Terrain Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13556230) - 2020 - CRC - 9/5/19
Vehicle Care 291
2.0L Gas Engine
1. Engine Cooling Fans (Outof View)
2. Engine Coolant Surge Tank and Pressure Cap
{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.
If the coolant inside the coolant
surge tank is boiling, do not do
anything else until it cools down.
The vehicle should be parked on a
level surface.
The coolant level should be at the
top rib on the middle of the tank. If it
is not, the vehicle may have a leak
at the radiator hoses, heater hoses,
radiator, water pump, or somewhere
else in the cooling system.
If there seems to be no leak, with
the engine on, check to see if the
electric engine cooling fan is
running. If the engine is overheating, the fan should be
running. If it is not, the vehicle
needs service. Turn off the engine.
Engine Coolant
The engine cooling system in the
vehicle is filled with DEX-COOL
engine coolant mixture. This coolant
needs to be checked and changed
at appropriate levels. See
Recommended Fluids and
Lubricants
0377 and
Maintenance Schedule 0368.
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 0294.
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
(Continued)

Page 296 of 425

GMC Terrain/Terrain Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13556230) - 2020 - CRC - 9/5/19
Vehicle Care 293
The coolant surge tank is located in
the engine compartment on the
driver side of the vehicle. See
Engine Compartment Overview
0278.
How to Add Coolant to the
Coolant Surge Tank
{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.
{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
Spilling coolant on hot engine
parts can burn you. Coolant
contains ethylene glycol and it will
burn if the engine parts are hot
enough.
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.
1. Remove the coolant surge tank
pressure cap when the cooling
system, including the coolant
surge tank pressure cap and
upper radiator hose, is no
longer hot.
Turn the pressure cap slowly
counterclockwise about
one-quarter of a turn. If you
hear a hiss, wait for that to

Page 297 of 425

GMC Terrain/Terrain Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13556230) - 2020 - CRC - 9/5/19
294 Vehicle Care
stop. This will allow any
pressure still left to be vented
out the discharge hose.
2. Keep turning the pressure cap slowly and remove it.
3. Fill the coolant surge tank withthe proper mixture to the
indicated level mark.
4. With the coolant surge tank pressure cap off, start the
engine and let it run until you
can feel the upper radiator
hose getting hot. Watch out for
the engine cooling fans. 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
indicated level mark.
5. Replace the pressure 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.
If the coolant still is not at the
proper level when the system
cools down again, see your
dealer.
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 and overheat
messages in the Driver Information
Center (DIC) to warn of engine
overheating. See Engine Coolant
Temperature Gauge 0112.
The decision may be made not to lift
the hood when the engine coolant
temperature gauge is in the
overheat zone or an engine
overheat DIC message displays, but
instead to get service help right
away. See Roadside Assistance
Program 0389.
If the decision to lift the hood is
made, make sure the vehicle is
parked on a level surface. Then
check to see if the engine cooling
fan(s) are running. If the engine is
overheating, the fan(s) should be
running. If they are not, do not
continue to run the engine, and
have the vehicle serviced.