2004 GMC SIERRA cooling

Cooling System
When you decide it's safe to lift the hood, here's what
you'll see:
A. Coolant Surge Tank
B. Coolant Surge Tank Pressure Cap
C. Engine Fan
If the coolant inside the coolant surge tank is boiling,
don't do anything else until it cools down. The vehicle
should be parked on a level surface. 8100 V8 Engines
All Other Engines
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The coolant level should
be at or above the FULL
COLD mark. If it isn't,
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, start the engine again.
The engine cooling fan speed should increase when idle
speed is doubled by pushing the accelerator pedal
down. If it doesn't, your vehicle needs service. Turn off
the engine.
Notice:Engine damage from running your engine
without coolant is not covered by your warranty. See
ªOverheated Engine Protection Operating Modeº
in the Index for information on driving to a safe
place in an emergency.
Notice:Using coolant other than DEX-COOLžmay
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
ž(silicate-free) coolant in your vehicle.
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How to Add Coolant to the Coolant
Surge Tank for Gasoline Engines
If you haven't found a problem yet, check to see if
coolant is visible in the surge tank. If coolant is visible
but the coolant level isn't at or above the FULL
COLD mark, add a 50/50 mixture of
clean, drinkable
waterand DEX-COOLžcoolant 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 5-33for more
information.If no coolant is visible in the surge tank, add coolant as
follows:
{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 Ð even a little Ð 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.
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{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
CAUTION: (Continued)
CAUTION: (Continued)
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 a proper 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.
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1. Park the vehicle on a
level surface. 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.
2. 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.
3. Then keep turning the pressure cap slowly, and
remove it.4. Then ®ll the coolant surge tank with the proper
mixture, to the FULL COLD mark.
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5. 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.6. Then replace the
pressure cap. Be sure
the pressure cap is
hand-tight and
fully seated.
Engine Fan Noise
Your vehicle has a clutched engine cooling fan. When the
clutch is engaged, the fan spins faster to provide more air
to cool the engine. In most everyday driving conditions,
the fan is spinning slower and the clutch is not fully
engaged. This improves fuel economy and reduces fan
noise. Under heavy vehicle loading, trailer towing and/or
high outside temperatures, the fan speed increases as
the clutch more fully engages. So you may hear an
increase in fan noise. This is normal and should not be
mistaken as the transmission slipping or making extra
shifts. It is merely the cooling system functioning properly.
The fan will slow down when additional cooling is not
required and the clutch disengages.
You may also hear this fan noise when you start the
engine. It will go away as the fan clutch partially
disengages.
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Notice:The wrong wheel can also cause problems
with bearing life, brake cooling, speedometer or
odometer calibration, headlamp aim, bumper height,
vehicle ground clearance and tire or tire chain
clearance to the body and chassis.
Whenever a wheel, wheel bolt or wheel nut is replaced
on a dual wheel setup, check the wheel nut torque
after 100, 1,000 and 6,000 miles (160, 1 600 and
10 000 km) of driving. For proper torque, see ªWheel Nut
Torqueº under
Capacities and Speci®cations on
page 5-134.
See
Changing a Flat Tire on page 5-96for more
information.
Used Replacement Wheels
{CAUTION:
Putting a used wheel on your vehicle is
dangerous. You can't know how it's been used
or how far it's been driven. It could fail
suddenly and cause a crash. If you have to
replace a wheel, use a new GM original
equipment wheel.
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ApplicationCapacities
English Metric
Cooling System
After re®ll, the level must be rechecked. See ªCooling Systemº in the Index.
VORTECŸ 4300 V6 Automatic Transmission 14.0 quarts 13.0 L
VORTECŸ 4300 V6 Manual Transmission 15.0 quarts 14.0 L
VORTECŸ 4800 V8 Automatic Transmission 15.0 quarts 14.0 L
VORTECŸ 4800 V8 Manual Transmission 15.0 quarts 14.0 L
VORTECŸ 5300 V8 Automatic Transmission 14.0 quarts 13.0 L
VORTECŸ 5300 V8** Automatic Transmission 16.0 quarts 15.0 L
VORTECŸ 6000 V8 Automatic Transmission 13.0 quarts 12.0 L
VORTECŸ 6000 V8* Automatic Transmission 13.0 quarts 12.0 L
VORTECŸ 6000 V8 Manual Transmission 16.0 quarts 15.0 L
VORTECŸ 6000 V8* Manual Transmission 16.0 quarts 15.0 L
VORTECŸ 8100 V8 Manual Transmission 22.0 quarts 21.0 L
VORTECŸ 8100 V8 Automatic Transmission 21.0 quarts 20.0 L
* Vehicles equipped with the optional engine oil cooler.
** Vehicles equipped with the optional air conditioner.
Engine Oil With Filter
After re®ll, the level must be rechecked. Add enough engine oil so that the ¯uid is within the proper operating
range. See
Engine Oil on page 5-18.
VORTECŸ 4300 V6 (Vin W) 4.5 quarts 4.3 L
VORTECŸ 4800 V8 ( Vin V) 6.0 quarts 5.7 L
VORTECŸ 5300 V8 (Vin T) 6.0 quarts 5.7 L
VORTECŸ 6000 V8 (Vin U) 6.0 quarts 5.7 L
5-135