tow GMC YUKON 2003 Manual PDF

Coolant Surge Tank Pressure Cap
SeeEngine Compartment
Overview on page 5-12for
more information on
location.
The coolant surge tank pressure cap must be fully
installed on the coolant surge tank.
Notice:Your pressure cap is a pressure-type cap
and must be tightly installed to prevent coolant loss
and possible engine damage from overheating.
See“Capacities and Specications”for more
information.
Engine Overheating
You willfind a coolant temperature gage on your
vehicle’s instrument panel. SeeEngine Coolant
Temperature Gage on page 3-46. In addition, you will
find a LOW COOLANT LEVEL, ENGINE OVERHEATED
and a REDUCED ENGINE POWER message in the
DIC on the instrument panel. SeeDriver Information
Center (DIC) on page 3-53.
Overheated Engine Protection
Operating Mode (V8 Engines Only)
If an overheated engine condition exists and the
REDUCED ENGINE POWER message is displayed, an
overheat protection mode which alternatesfiring
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. See“Engine Oil”in the Index.
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If No Steam Is Coming From Your
Engine
An overheat warning, along with a low coolant message,
can indicate a serious problem. SeeLow Coolant
underDIC Warnings and Messages on page 3-64.
If you get an engine overheat warning with no low
coolant message, but see or hear no steam, the problem
may not be too serious. Sometimes the engine can
get a little too hot when you:
•Climb a long hill on a hot day.
•Stop after high-speed driving.
•Idle for long periods in traffic.
•Tow a trailer. SeeTowing a Trailer on page 4-61.
If you get the overheat warning with no sign of steam, try
this for a minute or so:
1. In heavy traffic, let the engine idle in neutral while
stopped. If it is safe to do so, pull off the road. Shift
to park or neutral and let the engine idle.
2. Turn on your heater to full hot at the highest fan
speed and open the window as necessary.If you no longer have the overheat warning, you can
drive. Just to be safe, drive slower for about 10 minutes.
If the warning doesn’t come back on, you can drive
normally.
If the warning continues, pull over, stop, and park your
vehicle right away.
If there’s still no sign of steam, you can push down the
accelerator until the engine speed is about twice as
fast as normal idle speed for at least three minutes while
you’re parked. If you still have the warning,turn off
the engine and get everyone out of the vehicleuntil it
cools down. Also, seeOverheated Engine Protection
Operating Modelisted previously in this section.
You may decide not to lift the hood but to get service
help right away.
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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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A. Low-Beam Headlamp
B. High-Beam Headlamp
2. Pull the headlamp assembly out.
3. Unplug the electrical connector.
4. Turn the old bulb counterclockwise and remove it
from the headlamp assembly.
5. Put the new bulb into the assembly and turn it
clockwise until it is tight. Use care not to touch
the bulb with yourfingers or hands.
6. Plug in the electrical connector.
7. Put the headlamp assembly back into the vehicle.
Install and tighten the two pins.
Front Turn Signal, Sidemarker and
Daytime Running Lamps
A. Sidemarker Lamp
B. Retainer Clip
C. Front Turn Signal Lamp
D. Daytime Running Lamp
1. Remove the headlamp assembly as mentioned
previously.
2. Press the retainer clip, located behind the turn
signal housing, towards the outside of the vehicle.
3. Pull the turn signal housing out from the vehicle.
4. Press the locking release lever, turn the bulb socket
counterclockwise and remove it from the turn signal
housing.
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Replacement Bulbs
Exterior Lamp Bulb Number
Low-Beam Headlamps 9006
High-Beam Headlamps 9005
Daytime Running Lamps (DRL 4114K
Front Roof Marker Lamp 194
Front Parking and Turn Lamp 3457A
Rear Marker Lamp, Taillamp and
Stop Lamp3157
Rear Turn Lamp 3157
Back-up Lamp 3157
For any bulb not listed here contact your dealer.
Windshield Wiper Blade
Replacement
Windshield wiper blades should be inspected at least
twice a year for wear and cracking. SeeAt Least Twice
a Year on page 6-12for more information.
Replacement blades come in different types and are
removed in different ways. For proper type and length,
seeNormal Maintenance Replacement Parts on
page 5-109.To replace the windshield wiper blade assembly do the
following:
1. Lift the wiper arm and turn the blade until it is
facing away from the windshield.
2. Push the release lever and slide the wiper assembly
toward the driver’s side of the vehicle.
3. Install a new blade by reversing Steps 1 and 2.
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The purpose of regular rotation is to achieve more
uniform wear for all tires on the vehicle. Thefirst rotation
is the most important. See“Part A: Scheduled
Maintenance Services,”in Section 6, for scheduled
rotation intervals.
When rotating your tires, always use the correct rotation
pattern shown here.
After the tires have been rotated, adjust the front and
rear inflation pressures as shown on the
Certification/Tire label. Make certain that all wheel nuts
are properly tightened. See“Wheel Nut Torque”
underCapacities and Specifications on page 5-106.
{CAUTION:
Rust or dirt on a wheel, or on the parts to
which it is fastened, can make wheel nuts
become loose after a time. The wheel could
come off and cause an accident. When you
change a wheel, remove any rust or dirt from
places where the wheel attaches to the vehicle.
In an emergency, you can use a cloth or a
paper towel to do this; but be sure to use a
scraper or wire brush later, if you need to, to
get all the rust or dirt off. See“Changing a Flat
Tire”in the Index.
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If a Tire Goes Flat
It’s unusual for a tire to“blowout”while you’re driving,
especially if you maintain your tires properly. If air goes
out of a tire, it’s much more likely to leak out slowly.
But if you should ever have a“blowout”, here are a few
tips about what to expect and what to do:
If a front tire fails, theflat tire will create a drag that
pulls the vehicle toward that side. Take your foot off the
accelerator pedal and grip the steering wheelfirmly.
Steer to maintain lane position, and then gently brake to
a stop well out of the traffic lane.
A rear blowout, particularly on a curve, acts much like a
skid and may require the same correction you’d use
in a skid. In any rear blowout, remove your foot from the
accelerator pedal. Get the vehicle under control by
steering the way you want the vehicle to go. It may be
very bumpy and noisy, but you can still steer. Gently
brake to a stop—well off the road if possible.
If a tire goesflat, the next part shows how to use your
jacking equipment to change aflat tire safely.
Changing a Flat Tire
If a tire goesflat, avoid further tire and wheel damage
by driving slowly to a level place. Turn on your
hazard warningflashers.
{CAUTION:
Changing a tire can cause an injury. The
vehicle can slip off the jack and roll over you
or other people. You and they could be badly
injured. Find a level place to change your tire.
To help prevent the vehicle from moving:
1. Set the parking brakermly.
2. Put the shift lever in PARK (P).
3. Turn off the engine.
4. Put the wheel blocks at the front and rear
of the tire farthest away from the one
being changed. That would be the tire on
the other side of the vehicle, at the
opposite end.
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3. Insert the hoist end
(open end) (F) of the
extension through
the hole (G) in the rear
bumper.
Be sure the hoist end of the extension connects to
the hoist shaft (E). The ribbed square end of the
extension is used to lower the spare tire.
4. Turn the wheel wrench (H) counterclockwise to
lower the spare tire to the ground. Continue to
turn the wheel wrench until the spare tire can be
pulled out from under the vehicle.
If the spare tire does not lower to the ground, the
secondary latch is engaged causing the tire
not to lower. See“Secondary Latch System”later in
this section.5. The wheel wrench has
a hook that allows you
to pull the hoist
cable towards you to
assist in reaching
the spare tire.
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4. Remove all the wheel
nuts and take off the
flat tire.
5. Remove any rust or dirt
from the wheel bolts,
mounting surfaces
and spare wheel.
{CAUTION:
Rust or dirt on the wheel, or on the parts to
which it is fastened, can make the wheel nuts
become loose after a time. The wheel could
come off and cause an accident. When you
change a wheel, remove any rust or dirt from
the places where the wheel attaches to the
vehicle. In an emergency, you can use a cloth
or a paper towel to do this; but be sure to use
a scraper or wire brush later, if you need to, to
get all the rust or dirt off.
{CAUTION:
Never use oil or grease on studs or nuts. If
you do, the nuts might come loose. Your wheel
could fall off, causing a serious accident.
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6. After mounting the
spare, put the wheel
nuts back on with the
rounded end of the nuts
toward the wheel.
Tighten each wheel nut
by hand. Then use the
wheel wrench to tighten
the nuts until the wheel
is held against the hub.
7. Turn the wheel wrench counterclockwise to lower
the vehicle. Lower the jack completely.8. Tighten the nutsfirmly in a crisscross sequence as
shown by turning the wheel wrench clockwise.
{CAUTION:
Incorrect wheel nuts or improperly tightened
wheel nuts can cause the wheel to come loose
and even come off. This could lead to an
accident. Be sure to use the correct wheel
nuts. If you have to replace them, be sure to
get new GM original equipment wheel nuts.
Stop somewhere as soon as you can and have
the nuts tightened with a torque wrench to the
proper torque specication. See“Capacities
and Specications”in the Index for wheel nut
torque specication.
Notice:Improperly tightened wheel nuts can lead
to brake pulsation and rotor damage. To avoid
expensive brake repairs, evenly tighten the wheel
nuts in the proper sequence and to the proper
torque specication. See“Capacities and
Specications”in the index for the wheel nut torque
specication.
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