2003 GMC SIERRA DENALI light

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Higher Speeds (40 m.p.h./64 km/h and above)
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At higher speeds the front and rear wheels will turn in
the same direction. This improves stability of the vehicle
during lane changes and sweeping turns.
(4 Wheel Steer tow mode): When towing a trailer
the
4 wheel steer tow mode provides enhanced
stability allowing the trailer to follow the path of the tow
vehicle more closely, especially during lane changes.
In this mode the system operates much like the
4 mode,
but is enhanced for trailer towing. It is recommended
for all types and weights
of trailers.
To engage the
4 wheel steer tow mode, press the 4
Wheel Steer button until the 4 and tow indicators light up
on the instrument panel.
If the tow indicator is flashing
you will have to center the steering wheel by turning it to
the left or right. While in the
4 wheel steer tow mode,
it is possible the steering wheel may be slightly
off
center. For more information, see Towing a Trailer on
page
4-5 I.
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Car Washes for
QUADRASTEERTM Equipped Vehicles
Notice: Because your vehicle has a wider rear track
a small number
of older car washes may be too
narrow for your vehicle. Conveyor systems on some
automatic car washes may damage your vehicle.
Only use conveyor system car washes with 13-inch
(33 cm) wide conveyor rails and/or stationary
washes with at least 82 inches (208 cm) between the
rails. Before using the car wash check with the
manager.
13 in. 13 in.
(33 cm) (33 . 1. cm)
Off -Road Recovery
You may find that your right wheels have dropped off
the edge of a road onto the shoulder while you’re
driving.
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If the level of the shoulder is only slightly below the
pavement, recovery should be fairly easy. Ease
off the
accelerator and then,
if there is nothing in the way,
steer
so that your vehicle straddles the edge of
the pavement.
You can turn the steering wheel up to
one-quarter turn until the right front tire contacts
the pavement edge, Then turn your steering wheel to go
straight down the roadway.
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Surface Obstacles: Unseen or hidden obstacles can
be hazardous. A rock, log, hole, rut or bump can startle
you
if you’re not prepared for them. Often these
obstacles are hidden by grass, bushes, snow or even
the rise and fall of the terrain itself. Here are some
things to consider:
Is the path ahead clear?
Will the surface texture change abruptly up ahead?
Does the travel take you uphill or downhill?
(There’s more discussion of these subjects later.)
Will you have to stop suddenly or change direction
quickly?
When you drive over obstacles or rough terrain, keep a
firm grip on the steering wheel. Ruts, toughs or other
surface features can jerk the wheel out of your hands
if
you’re not prepared.
When you drive over bumps, rocks, or other obstacles,
your wheels can leave the ground. If this happens,
even with one or two wheels, you can’t control
the vehicle as well or at all. Because you
will be on an unpaved surface, it’s
especially important to avoid sudden acceleration,
sudden turns or sudden braking.
In a way, off-road driving requires a different kind of
alertness from driving on paved roads and highways.
There are no road signs, posted speed limits or
signal lights. You have to use your own good judgment
about what is safe and what isn’t.
Drinking and driving can be very dangerous on any
road. And this is certainly true for off-road driving. At the
very time you need special alertness and driving
skills, your reflexes, perceptions and judgment can be
affected by even
a small amount of alcohol. You
could have a serious
- or even fatal - accident if you
drink and drive or ride with a driver who has been
drinking. See
Drunken Driving on page 4-2.
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Q: Suppose, after stalling, I try to back down the hill
A: Set the parking brake, put your transmission in
PARK (P) and turn
off the engine. Leave the
vehicle and go get some help. Exit
on the uphill
side and stay clear of the path the vehicle would
take
if it rolled downhill.
and decide
I just can’t
do it. What should I do?
Driving Downhill
When off-roading takes you downhill, you’ll want to
consider a number of things:
How steep is the downhill? Will I be able to maintain
vehicle control?
What’s the surface like? Smooth? Rough? Slippery?
Hard-packed dirt? Gravel?
0 Are there hidden surface obstacles? Ruts? Logs?
What’s at the bottom of the hill? Is there a hidden
Boulders?
creek bank or even a river bottom with large
rocks?
If you decide you can go down a hill safely, then try to
keep your vehicle headed straight down, and use a
low gear. This way, engine drag can help your brakes
and they won’t hate to do all the work. Descend slowly,
keeping your vehicle under control at all times. Heavy
braking when going down a
h can
cause your brakes to overheat and fade. This
could cause
loss of control and a serious
accident. Apply the brakes lightly when
descending a hill and use
a low gear to keep
vehicle speed under control.
Q: Are there some things I should not do when
A: Yes! These are important because if you ignore
driving
down a hill?
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them you could lose control and have a serious
accident.
When driving downhill, avoid turns that take you
across the incline
of the hill. A hill that’s not too
steep to drive down may be too steep to drive
across. You could roll over
if you don’t drive straight
down.
Never go downhill with the transmission in
NEUTRAL (N).
This is called “free-wheeling.” Your brakes will have
to do all the work and could overheat and fade.
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Driving at Night
Night driving is more dangerous than day driving. One
reason is that some drivers are likely to be impaired
- by
alcohol or drugs, with night vision problems, or by fatigue.
Here are some tips on night driving.
Drive defensively.
0 Don’t drink and drive.
0 Adjust your inside rearview mirror to reduce the
glare from headlamps behind you.
Since you can’t see as well, you may need to slow
down and keep more space between you and
other vehicles.
Slow down, especially on higher speed roads. Your
headlamps can light up only
so much road ahead.
In remote areas, watch for animals.
If you’re tired, pull off the road in a safe place
and rest.
No one can see as well at night as
in the daytime. But
as we get older these differences increase.
A
50-year-old driver may require at least twice as much
light to see the same thing at night as a 20-year-old.
What you do in the daytime can also affect your
night vision. For example,
if you spend the day in bright
sunshine you are wise to wear sunglasses. Your
eyes will have less trouble adjusting to night. But
if
you’re driving, don’t wear sunglasses at night. They may
cut down on glare from headlamps, but they also
make a lot of things invisible.
You can be temporarily blinded by approaching
headlamps. It can take a second
or two, or even several
seconds, for your eyes to re-adjust 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.
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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.
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The heavier the rain, the harder it is to see. Even if your
windshield wiper blades are in good shape, a heavy
rain can make it harder to see road signs and
traffic signals, pavement markings, the edge of the road
and even people walking.
It's wise to keep your wiping equipment in good shape
and keep your windshield washer tank filled with
washer fluid. Replace your windshield wiper inserts
when they show signs of streaking or missing areas on
the windshield, or when strips of rubber start to
separate from the inserts. Driving too fast through large
water puddles or even
going through some car washes can cause problems,
too. The water may affect your brakes. Try to avoid
puddles. But
if you can't, try to slow down before you
hit them.
Wet brakes
4 1 cause accidents. They won't
work as well in a quick stop and may cause
pulling
to one side. You could lose control of
the vehicle.
After driving through a large puddle of water
or a car wash, apply your brake pedal lightly
until your brakes work normally.
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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.
Driving Through Flowhg W=+er
--m
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 5-6 I.
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