2003 GMC YUKON cooling

How to Add Coolant to the Coolant
Surge Tank
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 ofclean, drinkable waterand
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. SeeEngine
Coolant on page 5-26for 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—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.
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2003 - Yukon/Yukon XL

{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 wouldn’t get the overheat warning.
Your engine could catchre 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. Don’t spill coolant on a hot engine.
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.
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4. Thenfill the coolant surge tank with the proper
mixture, to the FULL COLD mark.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.
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2003 - Yukon/Yukon XL

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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2003 - Yukon/Yukon XL

{CAUTION:
Using the wrong replacement wheels, wheel
bolts or wheel nuts on your vehicle can be
dangerous. It could affect the braking and
handling of your vehicle, make your tires lose
air and make you lose control. You could have
a collision in which you or others could be
injured. Always use the correct wheel, wheel
bolts and wheel nuts for replacement.
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.
SeeChanging a Flat Tire on page 5-69for 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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Capacities and Specications
Please refer toPart D: Recommended Fluids and Lubricants on page 6-17for more information. All capacities are
approximate.
Capacities and Specications
Engine Type VIN Code Spark Plug Gap
VORTEC™4800 V8 V8 V 0.060 inches (1.52 mm)
VORTEC™5300 V8 V8 T 0.060 inches (1.52 mm)
VORTEC™5300 V8 V8 Z 0.060 inches (1.52 mm)
VORTEC™6000 V8 V8 U 0.060 inches (1.52 mm)
VORTEC™8100 V8 V8 G 0.060 inches (1.52 mm)
Wheels and Tires
Model Description Torque
C/K 1500 6 bolts (14 mm) 140 lb ft (190Y)
C/K 2500 8 bolts (14 mm) 140 lb ft (190Y)
Tire PressureSee the Certification/Tire label on the rear edge of the driver’s door or the
incomplete vehicle document in the cab.
After refill, the level must be rechecked. SeeCooling
System on page 5-32.
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Cooling System Capacity
ApplicationCapacities
English Metric
Cooling System
VORTEC™4800 V8 Automatic with front A/C 14.4 quarts 13.6 L
VORTEC™4800 V8 Automatic with front and rear A/C 15.8 quarts 15.0 L
VORTEC™5300 V8 Automatic with front A/C 14.4 quarts 13.6 L
VORTEC™5300 V8* Automatic with front and rear A/C 15.8 quarts 15.0 L
VORTEC™6000 V8 Automatic 15.8 quarts 15.0 L
VORTEC™6000 V8** Automatic with engine oil cooler 15.4 quarts 14.6 L
VORTEC™8100 V8 Automatic 20.7 quarts 19.6 L
*Vehicles equipped with the optional air conditioner.
**Vehicles equipped with the optional engine oil cooler.
Add one liter if equipped with rear heating for all engines.
After refill, the level must be rechecked. Add enough engine oil so that thefluid is within the proper operating range.
SeeEngine Oil on page 5-16.
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Maintenance Schedule......................................6-2
Introduction...................................................6-2
Your Vehicle and the Environment....................6-2
Maintenance Requirements..............................6-2
How This Section is Organized.........................6-3
Part A: Scheduled Maintenance Services...........6-4
Using Your Maintenance Schedule....................6-4
Scheduled Maintenance...................................6-5
Part B: Owner Checks and Services................6-11
At Each Fuel Fill..........................................6-11
At Least Once a Month.................................6-11
At Least Twice a Year...................................6-12At Least Once a Year
...................................6-12
Part C: Periodic Maintenance Inspections
.........6-15
Steering and Suspension Inspection
................6-15
Exhaust System Inspection
............................6-15
Fuel System Inspection
..................................6-15
Engine Cooling System Inspection
...................6-16
Transfer Case and Front Axle (Four-Wheel
Drive) Inspection
.......................................6-16
Brake System Inspection
................................6-16
Part D: Recommended Fluids and Lubricants
. . . .6-17
Part E: Maintenance Record
...........................6-19
Section 6 Maintenance Schedule
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2003 - Yukon/Yukon XL