2003 GMC YUKON DENALI headlamp

You can be temporarily blinded by approaching
headlamps.
It can take a second or two, or even several
seconds, for your eyes
to readjust to the dark. When
you are faced with severe glare (as from a driver
who doesn’t lower the high beams, or a vehicle with
misaimed headlamps),
slow down a little. Avoid staring
directly into the approaching headlamps.
Keep your windshield and all the glass on your vehicle
clean
- inside and out. Glare at night is made much
worse by dirt on the glass. Even the inside of the glass
can build up a film caused by dust. Dirty glass makes
lights dazzle and flash more than clean glass would,
making the pupils of your eyes contract repeatedly.
Remember that your headlamps light up far less of a
roadway when you are in a turn or curve. Keep
your eyes moving; that way, it’s easier
to pick out dimly
lighted objects.
Just as your headlamps should be
checked regularly for proper aim,
so should your eyes
be examined regularly. Some drivers suffer from
night blindness
- the inability to see in dim light - and
aren’t even aware of it.
Driving in Rain and on Wet Roads
Rain and wet roads can mean driving trouble. On a wet
road, you can’t stop, accelerate or turn
as well
because your tire-to-road traction isn’t as good as on
dry roads. And,
if your tires don’t have much tread left,
you’ll get even less traction.
It’s always wise to go
slower and be cautious
if rain starts to fall while you are
driving. The surface may get wet suddenly when your
reflexes are tuned for driving on dry pavement.
4-29

Hydroplaning
Hydroplaning is dangerous. So much water can build up
under your tires that they can actually ride on the
water. This can happen
if the road is wet enough and
you’re going fast enough. When your vehicle is
hydroplaning, it has little or no contact with the road.
Hydroplaning doesn’t happen often. But it can
if
your tires do not have much tread or if the pressure in
one or more is low. It can happen
if a lot of water is
standing on the road. If you can see reflections
from trees, telephone poles or other vehicles, and
raindrops “dimple” the water’s surface, there could be
hydroplaning.
Hydroplaning usually happens at higher speeds. There
just isn’t a hard and fast rule about hydroplaning.
The best advice is to slow down when
it is raining.
Driving Through Deep Standing Water
Notice: If you drive too quickly through deep
puddles or standing water, water can come
in
through your engine’s air intake and badly damage
your engine. Never drive through water that
is
slightly lower than the underbody of your vehicle. If
you can’t avoid deep puddles or standing water,
drive through them very slowly.
Drivhg Through Flowing Water
~~
I
Flowing or rushing water creates strong forces.
If you try to drive through flowing water, as you
might at a low water crossing, your vehicle can
be carried away.
As little as six inches of
flowing water can carry away a smaller vehicle.
If this happens, you and other vehicle
occupants could drown. Don’t ignore police
warning signs, and otherwise be very cautious
about trying to drive through flowing water.
Some Other Rainy Weather Tips
Turn on your low-beam headlamps - not just your
parking lamps
- to help make you more visible to
others.
* Besides slowing down, allow some extra following
distance. And be especially careful when you
pass another vehicle. Allow yourself more clear
room ahead, and be prepared to have your
view restricted by road spray.
* Have good tires with proper tread depth. See Tires
on page 5-55.
4-31

You can run the engine to keep warm, but be careful.
L..Jw can trap exhaust gases ,..der your
vehicle. This can cause deadly CO (carbon
monoxide) gas to get inside.
CO could
overcome you and kill you. You can’t see
it or
smell it, so you might not know it is in your
vehicle. Clear away snow from around the base of your vehicle, especially any that is
blocking your exhaust pipe. And check around
again from time to time to be sure snow
doesn’t collect there.
Open a window just
a little on the side of the
vehicle that’s away from the wind. This will
help keep
CO out.
Run your engine only
as long as you must. This saves
fuel. When
you run the engine, make it go a little
faster than just idle. That
is, push the accelerator
slightly. This uses less fuel for the heat that
you get and
it keeps the battery charged. You will need a
well-charged battery
to restart the vehicle, and possibly
for signaling later
on with your headlamps. Let the
heater run for
a while.
4-40

Section 5 Service and Appearance Care
Service ............................................................ 5.3
Doing Your Own Service Work
......................... 5-3
Adding Equipment
to the Outside of Your
Vehicle
.................................................. 5-4
................................................................ Fuel 5.5
Gasoline Octane ............................................ 5.5
Gasoline Specifications ................................... 5-5
California Fuel ............................................... 5-6
Additives
....................................................... 5.6
Fuels in Foreign Countries
............................... 5-6
Filling Your Tank
............................................ 5-7
Filling a Portable Fuel Container ....................... 5.9
the Hood .................... , .................... 5.10
Hood Release ...................... ................ 5-10
Engine Compartment Overview ....... ......... 5-12
Engine Oil ....................................... ..... 5.13
Engine Air Cleaner/Filter ............................. 5.17
Automatic Transmission Fluid ......................... 5-20
Engine Coolant ......................................... 5-22
Checking Things Under
~~
Coolant Surge Tank Pressure Cap ............... 5-25
Engine Overheating ....................................... 5-25
Cooling System ............................................ 5.28
Engine Fan Noise ......................................... 5.33
Power Steering Fluid
..................................... 5-34
Windshield Washer Fluid
................................ 5.34
Brakes
........................................................ 5.36
Battery
........................................................ 5-39
Jump Starting
............................................... 5.40
All-Wheel Drive .............................................. 5.46
Rear Axle .................................. .......... 5-48
Bulb Replacement .......................................... 5-49
Halogen Bulbs .............................................. 5-49
Headlamps
.................................................. 5-49
Running Lamps
......................................... 5-50
Center High-Mounted Stoplamp (CHMSL) ......... 5-52
Taillamps ..................................................... 5-52
Replacement Bulbs ................................... 5.53
Front Turn Signal, Sidemarker and Daytime
5- 1

Bulb Replacement
See Replacement Bulbs on page 5-53 for the proper
type
of bulbs to use.
For any bulb changing procedure not listed in this
section, contact your dealer.
Halogen Bulbs
Halogen bulbs have pressurized gas inside
and can burst if you drop or scratch the bulb.
You or others could be injured. Be sure to read
and
follow the instructions on the bulb
package.
Headlamps
1. Remove the two pins on the top of the headlamp
assembly.
To remove the pins, turn the outer pin
outward and pull
it straight up. To remove the inner
pin, turn it inward and pull it straight up.
5-49

A. Low-Beam Headlamp
B. High-Beam Headlamp
1. Pull the headlamp assembly out.
2. Unplug the electrical connector.
3. Turn the bulb counterclockwise and remove it from
the headlamp assembly.
4. Put the new bulb into the headlamp assembly and
turn it clockwise until it is tight. Use care not to
touch the bulb with your fingers or hands.
5. Plug in the electrical connector.
6. Put the headlamp assembly back into the vehicle.
7. Install and turn the two pins into the locking feature.
A. Sidemarker Lamp
B. Retainer Clip
C. Front Turn Signal Lamp
D. Daytime Running Lamp
1. Remove the headlamp assembly as mentioned
previously.
5-50

2. Press the retainer clip (B), 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.
5. Remove the bulb from the bulb socket.
6. Put the new bulb into the bulb socket.
7. Put the bulb socket into the turn signal housing and
turn it clockwise until it locks.
8. Put the turn signal housing back onto the vehicle
placing the hook and
posts on the inner side into
the alignment holes first and then the outer side into
the retainer bracket until you hear a click.
9. Put the headlamp assembly back into the vehicle.
5-5 1

Wheel Alignment and Tire Balance
The wheels on your vehicle were aligned and balanced
carefully at the factory
to give you the longest tire life
and best overall performance.
Scheduled wheel alignment and wheel balancing are
not needed. However,
if you notice unusual tire wear or
your vehicle pulling one way or the other, the alignment
may need
to be reset. If you notice your vehicle
vibrating when driving on a smooth road, your wheels
may need
to be rebalanced.
Wheel Replacement
Replace any wheel that is bent, cracked, or badly rusted
or corroded.
If wheel nuts keep coming loose, the
wheel, wheel bolts and wheel nuts should be replaced.
If the wheel leaks air, replace it (except some
aluminum wheels, which can sometimes be repaired).
See your dealer
if any of these conditions exist.
Your dealer will know the kind of wheel you need.
Each new wheel should have the same load-carrying
capacity, diameter, width, offset and be mounted
the same way as the one it replaces.
If you need to replace any of your wheels, wheel bolts
or wheel nuts, replace them only with new
GM
original equipment parts. This way, you will be sure to
have the right wheel, wheel bolts and wheel nuts
for your vehicle. 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 clearance to the
body and chassis.
See
Changing a Flat Tire on page 5-63 for more
information.
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