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GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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336 Vehicle Care
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.
If no coolant is visible in the surge
tank, add coolant.
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 full
turn. If a hiss is heard, wait for
that to stop. A hiss means
there is still some pressure left.
2. Keep turning the pressure cap slowly, and remove it.
3. Fill the coolant surge tank with the proper mixture to the full
cold mark.
4. With the coolant surge tank pressure cap off, start the
engine and let it run until the
engine coolant temperature
gauge indicates approximately
90 °C (195 °F).
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 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.
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
If the vehicle has the Duramax
diesel engine, see the Duramax
diesel supplement.
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.
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GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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Vehicle Care 337
The vehicle has several indicators
to warn of engine overheating.
There is a coolant temperature
gauge in the vehicle's instrument
cluster. SeeEngine Coolant
Temperature Gauge 0147.
In addition, there are ENGINE
OVERHEATED STOP ENGINE,
ENGINE OVERHEATED IDLE
ENGINE, and ENGINE POWER IS
REDUCED messages in the Driver
Information Center (DIC).
If the decision is made not to lift the
hood when this warning appears,
get service help right away. See
Roadside Assistance Program
0 442.
If the decision is made to lift the
hood, make sure the vehicle is
parked on a level surface.
2.7L L4, 4.3L V6, 5.3L V8, and 6.2L
V8 Engines
Check to see if the engine cooling
fans are running. If the engine is
overheating, the fans should be running. If they are not, do not
continue to run the engine. 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 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.
If No Steam is Coming from
the Engine Compartment
The ENGINE OVERHEATED STOP
ENGINE or the ENGINE
OVERHEATED IDLE ENGINE
message, along with a low coolant
condition, can indicate a serious
problem.The 2.7L engine will shut down
automatically if the ENGINE
OVERHEATED STOP ENGINE
message displays.
If there is an engine overheat
warning, but no steam is seen or
heard, the problem may not be too
serious. Sometimes the engine can
get a little too hot when the vehicle:
.
Climbs a long hill on a hot day.
. Stops after high-speed driving.
. Idles for long periods in traffic.
. Tows a trailer; see Trailer Towing
0 286.
If the ENGINE OVERHEATED
STOP ENGINE or the ENGINE
OVERHEATED IDLE ENGINE
message appears with no sign of
steam, try this for a minute or so: 1. Turn the air conditioning off.
2. Turn the heater on to the highest temperature and to the
highest fan speed. Open the
windows as necessary.
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GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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Service and Maintenance 421
the desiccant to help the longevity
and efficient operation of the air
conditioning system. This service
can be complex. See your dealer.
Tire Rotation and Required
Services Every 12 000 km/
7,500 mi
Rotate the tires, if recommended for
the vehicle, and perform the
following services. SeeTire
Rotation 0381.
. Check engine oil level and oil
life percentage. If needed,
change engine oil and filter, and
reset oil life system. See Engine
Oil 0326 and
Engine Oil Life System 0328.
. If equipped with the engine air
filter life system, check the air
filter life percentage.
If necessary, replace the engine
air filter and reset the engine air
filter life system. See Engine Air
Filter Life System 0330. If the
vehicle is not equipped with the
engine air filter life system, inspect the engine air cleaner
filter. See
Engine Air Cleaner/
Filter 0331.
. Check engine coolant level. See
Cooling System 0332.
. Check windshield washer fluid
level. See Washer Fluid 0339.
. Check tire inflation pressures,
including the spare. See Tire
Pressure 0372.
. Inspect tire wear. See Tire
Inspection 0380.
. Visually check for fluid leaks.
. Inspect brake system. See
Exterior Care 0408.
. Visually inspect steering,
suspension, and chassis
components for damage,
including cracks or tears in the
rubber boots, loose or missing
parts, or signs of wear at least
once a year. See Exterior Care
0 408. Lubricate the suspension
and steering components at
least every other oil change.
(If equipped with grease fittings) .
Inspect power steering for
proper attachment, connections,
binding, leaks, cracks,
chafing, etc.
. Visually inspect drive shafts for
excessive wear, lubricant leaks
or damage including: tube dents,
cracks, constant velocity joint or
universal joint looseness,
cracked or missing boots, loose
or missing boot clamps, center
bearing excessive looseness,
missing or loose fasteners.
. Check restraint system
components. See Safety System
Check 085.
. Visually inspect fuel system for
damage or leaks.
. Visually inspect exhaust system
and nearby heat shields for
loose or damaged parts.
. Lubricate body components. See
Exterior Care 0408.
. Check starter switch. See Starter
Switch Check 0348.