all GMC YUKON DENALI 2005 Owners Manual

Approaching a Hill
When you approach a hill, you need to decide if it is
one of those hills that is just too steep to climb, descend
or cross. Steepness can be hard to judge. On a very
small hill, for example, there may be a smooth, constant
incline with only a small change in elevation where
you can easily see all the way to the top. On a large hill,
the incline may get steeper as you near the top, but
you may not see this because the crest of the hill
is hidden by bushes, grass or shrubs.
Here are some things to consider as you approach a hill.
Is there a constant incline, or does the hill get sharply
steeper in places?
Is there good traction on the hillside, or will the
surface cause tire slipping?
Is there a straight path up or down the hill so you will
not have to make turning maneuvers?
Are there obstructions on the hill that can block your
path (boulders, trees, logs or ruts)?
What is beyond the hill? Is there a cliff, an
embankment, a drop-off, a fence? Get out and walk
the hill if you do not know. It is the smart way to
nd out.
Is the hill simply too rough? Steep hills often have
ruts, gullies, troughs, and exposed rocks because
they are more susceptible to the effects of erosion.
Driving Uphill
Once you decide you can safely drive up the hill, you
need to take some special steps.
Use a low gear and get a rm grip on the steering
wheel.
Get a smooth start up the hill and try to maintain
your speed. Do not use more power than you
need, because you do not want your wheels to start
spinning or sliding.
Try to drive straight up the hill if at all possible. If
the path twists and turns, you might want to nd
another route.
{CAUTION:
Turning or driving across steep hills can be
dangerous. You could lose traction, slide
sideways, and possibly roll over. You could be
seriously injured or killed. When driving up
hills, always try to go straight up.
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Ease up on your speed as you approach the top of
the hill.
Attach a ag to the vehicle to make you more
visible to approaching traffic on trails or hills.
Sound the horn as you approach the top of the hill
to let opposing traffic know you are there.
Use your headlamps even during the day. They
make you more visible to oncoming traffic.
{CAUTION:
Driving to the top (crest) of a hill at full speed
can cause an accident. There could be a
drop-off, embankment, cliff, or even another
vehicle. You could be seriously injured or
killed. As you near the top of a hill, slow down
and stay alert.
Q:What should I do if my vehicle stalls, or is about
to stall, and I cannot make it up the hill?
A:If this happens, there are some things you should
do and there are some things you must not do.
First, here is what youshoulddo:
Push the brake pedal to stop the vehicle and
keep it from rolling backwards. Also, apply the
parking brake.
If your engine is still running, shift the transmission
to REVERSE (R), release the parking brake, and
slowly back down the hill as straight as possible in
REVERSE (R).
As you are backing down the hill, put your left hand
on the steering wheel at the 12 o’clock position.
This way, you will be able to tell if your wheels are
straight and maneuver as you back down. It is
best that you back down the hill with your wheels
straight rather than in the left or right direction.
Turning the wheel too far to the left or right
will increase the possibility of a rollover.
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Here are some things youmust notdo if you stall, or
are about to stall, when going up a hill.
Never attempt to prevent a stall by shifting into
NEUTRAL (N) to rev-up the engine and regain
forward momentum. This will not work. Your vehicle
will roll backwards very quickly and you could go
out of control.
Instead, apply the regular brake to stop the
vehicle. Then apply the parking brake. Shift to
REVERSE (R), release the parking brake,
and slowly back straight down.
Never attempt to turn around if you are about to
stall when going up a hill. If the hill is steep
enough to stall your vehicle, it is steep enough to
cause you to roll over if you turn around. If you
cannot make it up the hill, you must back straight
down the hill.
Q:Suppose, after stalling, I try to back down the
hill and decide I just cannot do it. What should
I do?
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.
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Driving Downhill
When off-roading takes you downhill, you will want to
consider a number of things:
How steep is the downhill? Will I be able to maintain
vehicle control?
What is the surface like? Smooth? Rough?
Slippery? Hard-packed dirt? Gravel?
Are there hidden surface obstacles? Ruts? Logs?
Boulders?
What is at the bottom of the hill? Is there a hidden
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 will not have to do all the work. Descend
slowly, keeping your vehicle under control at all times.
{CAUTION:
Heavy braking when going down a hill 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
driving down a hill?
A:Yes! These are important because if you ignore 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 is not too steep
to drive down may be too steep to drive across. You
could roll over if you do not 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.
Q:Am I likely to stall when going downhill?
A:It is much more likely to happen going uphill. But if
it happens going downhill, here is what to do.
1. Stop your vehicle by applying the regular brakes.
Apply the parking brake.
2. Shift to PARK (P) and, while still braking, restart
the engine.
3. Shift back to a low gear, release the parking brake,
and drive straight down.
4. If the engine will not start, get out and get help.
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Stalling on an Incline
If your vehicle stalls when you are crossing an incline,
be sure you (and your passengers) get out on the uphill
side, even if the door there is harder to open. If you
get out on the downhill side and the vehicle starts to roll
over, you will be right in its path.
If you have to walk down the slope, stay out of the path
the vehicle will take if it does roll over.{CAUTION:
Getting out on the downhill (low) side of a
vehicle stopped across an incline is
dangerous. If the vehicle rolls over, you could
be crushed or killed. Always get out on the
uphill (high) side of the vehicle and stay well
clear of the rollover path.
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Driving in Mud, Sand, Snow or Ice
When you drive in mud, snow or sand, your wheels will
not get good traction. You cannot accelerate as quickly,
turning is more difficult, and you will need longer braking
distances.
It is best to use a low gear when you are in mud — the
deeper the mud, the lower the gear. In really deep
mud, the idea is to keep your vehicle moving so you do
not get stuck.
When you drive on sand, you will sense a change in
wheel traction. But it will depend upon how loosely
packed the sand is. On loosely packed sand (as on
beaches or sand dunes) your tires will tend to sink into
the sand. This has an effect on steering, accelerating and
braking. Drive at a reduced speed and avoid sharp turns
or abrupt maneuvers.
Hard packed snow and ice offer the worst tire traction.
On these surfaces, it is very easy to lose control.
On wet ice, for example, the traction is so poor that you
will have difficulty accelerating. And if you do get
moving, poor steering and difficult braking can cause
you to slide out of control.{CAUTION:
Driving on frozen lakes, ponds or rivers can be
dangerous. Underwater springs, currents
under the ice, or sudden thaws can weaken the
ice. Your vehicle could fall through the ice and
you and your passengers could drown. Drive
your vehicle on safe surfaces only.
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Driving in Water
Heavy rain can mean ash ooding, and ood waters
demand extreme caution.
Find out how deep the water is before you drive through
it. If it is deep enough to cover your wheel hubs,
axles or exhaust pipe, do not try it — you probably will
not get through. Also, water that deep can damage
your axle and other vehicle parts.
If the water is not too deep, drive slowly through it.
At faster speeds, water splashes on your ignition system
and your vehicle can stall. Stalling can also occur if
you get your tailpipe under water. And, as long as your
tailpipe is under water, you will never be able to
start your engine. When you go through water,
remember that when your brakes get wet, it may take
you longer to stop.{CAUTION:
Driving through rushing water can be
dangerous. Deep water can sweep your vehicle
downstream and you and your passengers
could drown. If it is only shallow water, it can
still wash away the ground from under your
tires, and you could lose traction and roll
the vehicle over. Do not drive through
rushing water.
SeeDriving in Rain and on Wet Roads on page 4-31for
more information on driving through water.
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Here are some tips on night driving.
Drive defensively.
Do not drink and drive.
Since you cannot 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 are 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 are driving,
do not 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 does not 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 lm caused by dust. Dirty glass makes
lights dazzle and ash 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 is 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
are not even aware of it.
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Driving in Rain and on Wet Roads
Rain and wet roads can mean driving trouble. On a wet
road, you cannot stop, accelerate, or turn as well
because your tire-to-road traction is not as good as on
dry roads. And, if your tires do not have much tread
left, you will get even less traction. It is 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 reexes are tuned for driving on dry pavement.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 is wise to keep your wiping equipment in good shape
and keep your windshield washer tank lled with washer
uid. 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 cannot, try to slow down before you
hit them.
{CAUTION:
Wet brakes can cause accidents. They will not
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 are going fast enough. When your vehicle
is hydroplaning, it has little or no contact with the road.
Hydroplaning does not 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 reections
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 is not 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 cannot avoid deep puddles or standing water,
drive through them very slowly.
Driving Through Flowing Water
{CAUTION:
Flowing or rushing water creates strong forces.
If you try to drive through owing water, as you
might at a low water crossing, your vehicle can
be carried away. As little as six inches of
owing water can carry away a smaller vehicle.
If this happens, you and other vehicle
occupants could drown. Do not ignore police
warning signs, and otherwise be very cautious
about trying to drive through owing 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. SeeTires
on page 5-56.
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