2005 GMC SIERRA DENALI engine coolant

If you get the overheat warning with no sign of steam,
try this for a minute or so:
1. If your air conditioner is on, turn it off.
2. Turn on your heater to full hot at the highest fan
speed and open the windows as necessary.
3. If you are in a traffic jam, shift to NEUTRAL (N);
otherwise, shift to the highest gear while
driving — DRIVE (D).
If you no longer have the overheat warning, you can
drive. Just to be safe, drive slower for about 10 minutes.
If the warning does not come back on, you can drive
normally.
If the warning continues, pull over, stop, and park your
vehicle right away.
If there is still no sign of steam and your vehicle is
equipped with an engine-driven cooling fan, push down
the accelerator until the engine speed is about twice
as fast as normal idle speed for at least three minutes
while you are parked.
If there is still no sign of steam and your vehicle is
equipped with an electric engine cooling fan, idle the
engine for three minutes while you are parked.If you still have the warning,turn off the engine and get
everyone out of the vehicleuntil it cools down. Also,
see “Overheated Engine Protection Operating Mode”
later in this section.
You may decide not to lift the hood but to get service
help right away.
Overheated Engine Protection
Operating Mode
If an overheated engine condition exists and the
REDUCED ENGINE POWER message is displayed, an
overheat protection mode which alternates ring
groups of cylinders helps prevent engine damage. In
this mode, you will notice a loss in power and engine
performance. This operating mode allows your vehicle to
be driven to a safe place in an emergency. Driving
extended miles (km) and/or towing a trailer in the
overheat protection mode should be avoided.
Notice:After driving in the overheated engine
protection operating mode, to avoid engine damage,
allow the engine to cool before attempting any
repair. The engine oil will be severely degraded.
Repair the cause of coolant loss, change the oil and
reset the oil life system. SeeEngine Oil on
page 5-14.
5-28

Cooling System
When you decide it is safe to lift the hood, here is what
you will see:
A. Coolant Surge Tank
B. Coolant Surge Tank Pressure Cap
C. Electric Engine Cooling Fan (If Equipped){CAUTION:
An electric fan under the hood can start up
and injure you even when the engine is not
running. Keep hands, clothing and tools away
from any underhood electric fan.
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.
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The coolant level should
be at or above the FULL
COLD mark. If it is not, you
may have a leak at the
pressure cap or in
the radiator hoses, heater
hoses, radiator, water
pump or somewhere else
in the cooling system.
{CAUTION:
Heater and radiator hoses, and other engine
parts, can be very hot. Do not touch them. If
you do, you can be burned.
Do not run the engine if there is a leak. If you
run the engine, it could lose all coolant. That
could cause an engine re, and you could be
burned. Get any leak xed before you drive the
vehicle.If there seems to be no leak and your vehicle is
equipped with an electric engine cooling fan, with the
engine on check to see if the cooling fan is running. If it
is not, your vehicle needs service. Turn off the engine.
If there seems to be no leak and your vehicle is
equipped with an engine-driven cooling fan, start the
engine again and see if the fan speed increases when
idle speed is doubled by pushing the accelerator
pedal down. If it does not, your vehicle needs service.
Turn off the engine.
Notice:Engine damage from running your engine
without coolant is not covered by your warranty. See
Overheated Engine Protection Operating Mode on
page 5-28for information on driving to a safe place
in an emergency.
Notice:Using coolant other than DEX-COOL
®may
cause premature engine, heater core or radiator
corrosion. In addition, the engine coolant may
require changing sooner, at 30,000 miles (50 000 km)
or 24 months, whichever occurs rst. Any repairs
would not be covered by your warranty. Always use
DEX-COOL
®(silicate-free) coolant in your vehicle.
5-30

How to Add Coolant to the Coolant
Surge Tank
If you have not found a problem yet, check to see if
coolant is visible in the surge tank. If coolant is visible
but the coolant level is not at or above the FULL COLD
mark, add a 50/50 mixture ofclean, drinkable water
and DEX-COOL
®coolant at the coolant surge tank, but
be sure the cooling system, including the coolant
surge tank pressure cap, is cool before you do it. See
Engine Coolant on page 5-24for more information.
{CAUTION:
Steam and scalding liquids from a hot cooling
system can blow out and burn you badly. They
are under pressure, and if you turn the coolant
surge tank pressure cap — even a little — they
can come out at high speed. Never turn the
cap when the cooling system, including the
coolant surge tank pressure cap, is hot. Wait
for the cooling system and coolant surge tank
pressure cap to cool if you ever have to turn
the pressure cap.
5-31

{CAUTION:
Adding only plain water to your cooling
system can be dangerous. Plain water, or
some other liquid such as alcohol, can boil
before the proper coolant mixture will. Your
vehicle’s coolant warning system is set for the
proper coolant mixture. With plain water or the
wrong mixture, your engine could get too hot
but you would not get the overheat warning.
Your engine could catch re and you or others
could be burned. Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
®coolant.
Notice:In cold weather, water can freeze and crack
the engine, radiator, heater core and other parts.
Use the recommended coolant and the proper
coolant mixture.
{CAUTION:
You can be burned if you spill coolant on hot
engine parts. Coolant contains ethylene glycol
and it will burn if the engine parts are hot
enough. Do not spill coolant on a hot engine.
1. You can 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
(left) about one full turn. If you hear a hiss, wait for
that to stop. A hiss means there is still some
pressure left.
2. Then keep turning the pressure cap slowly, and
remove it.
5-32

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 you can feel the upper
radiator hose 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 FULL COLD mark.
5. Then replace the pressure cap. Be sure the
pressure cap is hand-tight and fully seated.
5-33

Windshield Washer Fluid
What to Use
When you need windshield washer uid, be sure to read
the manufacturer’s instructions before use. If you will
be operating your vehicle in an area where the
temperature may fall below freezing, use a uid that has
sufficient protection against freezing.
Adding Washer Fluid
Your vehicle has a low washer uid message that
comes on when the washer uid is low. The message is
displayed for 15 seconds at the start of each ignition
cycle. When the CHECK WASHER FLUID message is
displayed, you will need to add washer uid to the
windshield washer uid reservoir.
Open the cap with the
washer symbol on it. Add
washer uid until the
tank is full. SeeEngine
Compartment Overview on
page 5-12for reservoir
location.Notice:
When using concentrated washer uid, follow
the manufacturer’s instructions for adding
water.
Do not mix water with ready-to-use washer uid.
Water can cause the solution to freeze and
damage your washer uid tank and other parts
of the washer system. Also, water does not
clean as well as washer uid.
Fill your washer uid tank only three-quarters
full when it is very cold. This allows for
expansion if freezing occurs, which could
damage the tank if it is completely full.
Do not use engine coolant (antifreeze) in your
windshield washer. It can damage your washer
system and paint.
5-36

Scheduled Maintenance
Service MaintenanceIMaintenanceII
Change engine oil and lter. SeeEngine Oil on page 5-14. Reset oil life
system. SeeEngine Oil Life System on page 5-17.An Emission Control
Service.••
Lubricate chassis components.See footnote #.••
Visually check for any leaks or damage.See footnote (j).••
Inspect engine air cleaner lter or change indicator (if equipped). If necessary,
replace lter. SeeEngine Air Cleaner/Filter on page 5-19.An Emission Control
Service. See footnotes † and (k).•
Rotate tires and check ination pressures and wear. SeeTires on page 5-56.••
Inspect brake system.See footnote (a).••
Check engine coolant and windshield washer uid levels and add uid as
needed.••
Perform any needed additional services. See “Additional Required Services” in
this section.••
Inspect suspension and steering components.See footnote (b).•
Inspect engine cooling system.See footnote (c).•
Inspect wiper blades.See footnote (d).•
Inspect restraint system components.See footnote (e).•
Lubricate body components.See footnote (f).•
Check transmission uid level and add uid as needed.•
6-5