GMC Canyon/Canyon Denali Owner Manual (GMNA-Localizing-U.S./Canada-
13566643) - 2020 - CRC - 10/4/19
Vehicle Care 235
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.
GMC Canyon/Canyon Denali Owner Manual (GMNA-Localizing-U.S./Canada-
13566643) - 2020 - CRC - 10/4/19
236 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 withthe 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 0104.
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.
