stop GMC ENVOY DENALI 2007 Manual PDF

Loss of Control
Let us review what driving experts say about what
happens when the three control systems — brakes,
steering, and acceleration — do not have enough
friction where the tires meet the road to do what the
driver has asked.
In any emergency, do not give up. Keep trying to
steer and constantly seek an escape route or
area of less danger.
Skidding
In a skid, a driver can lose control of the vehicle.
Defensive drivers avoid most skids by taking
reasonable care suited to existing conditions, and
by not overdriving those conditions. But skids
are always possible.
The three types of skids correspond to your
vehicle’s three control systems. In the braking skid,
your wheels are not rolling. In the steering or
cornering skid, too much speed or steering in a
curve causes tires to slip and lose cornering force.
And in the acceleration skid, too much throttle
causes the driving wheels to spin.
A cornering skid is best handled by easing your
foot off the accelerator pedal.If your vehicle starts to slide, ease your foot off
the accelerator pedal and quickly steer the
way you want the vehicle to go. If you start
steering quickly enough, your vehicle may
straighten out. Always be ready for a second skid
if it occurs.
Of course, traction is reduced when water, snow,
ice, gravel, or other material is on the road.
For safety, you will want to slow down and adjust
your driving to these conditions. It is important
to slow down on slippery surfaces because
stopping distance will be longer and vehicle control
more limited.
While driving on a surface with reduced traction, try
your best to avoid sudden steering, acceleration, or
braking, including reducing vehicle speed by
shifting to a lower gear. Any sudden changes could
cause the tires to slide. You may not realize the
surface is slippery until your vehicle is skidding.
Learn to recognize warning clues — such as
enough water, ice, or packed snow on the road to
make a mirrored surface — and slow down when
you have any doubt.
Remember: Any Anti-Lock Brake System (ABS)
helps avoid only the braking skid.
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Loading Your Vehicle for Off-Road
Driving
{CAUTION:
Cargo on the load oor piled higher
than the seatbacks can be thrown
forward during a sudden stop. You or
your passengers could be injured.
Keep cargo below the top of the
seatbacks.
Unsecured cargo on the load oor can
be tossed about when driving over
rough terrain. You or your passengers
can be struck by ying objects.
Secure the cargo properly.
Heavy loads on the roof raise the
vehicle’s center of gravity, making it
more likely to roll over. You can be
seriously or fatally injured if the
vehicle rolls over. Put heavy loads
inside the cargo area, not on the roof.
Keep cargo in the cargo area as far
forward and low as possible.There are some important things to remember
about how to load your vehicle.
The heaviest things should be on the
load oor and forward of the rear axle.
Put heavier items as far forward as you can.
Be sure the load is secured properly, so
driving on the off-road terrain does not
toss things around.
You will nd other important information in this
manual. SeeLoading Your Vehicle on page 349,
Luggage Carrier on page 161, andTires on
page 439.
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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 are 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 is 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 rm grip on the steering wheel. Ruts,
troughs, or other surface features can jerk
the wheel out of your hands if you are not
prepared.When you drive over bumps, rocks, or other
obstacles, the wheels can leave the ground.
If this happens, even with one or two wheels,
you cannot control the vehicle as well or at all.
Because you will be on an unpaved surface, it is
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 is not.
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 reexes, 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.
SeeDrunken Driving on page 303.
323

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 the engine is still running, shift the
transmission to REVERSE (R), release the
parking brake, and slowly back down the
hill in REVERSE (R).
If the engine has stopped running, you will need
to restart it. With the brake pedal pressed and
the parking brake still applied, shift the
transmission to PARK (P) and restart the
engine. Then, shift 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 the
wheels are straight and maneuver as you back
down. It is best that you back down the hill with
the 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.
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.
326

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.”
The 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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Q:What if I am driving across an incline that
is not too steep, but I hit some loose
gravel and start to slide downhill.
What should I do?
A:If you feel your vehicle starting to slide
sideways, turn downhill. This should help
straighten out the vehicle and prevent the side
slipping. However, a much better way to
prevent this is to get out and “walk the course”
so you know what the surface is like before
you drive it.
Stalling on an Incline
If your vehicle stalls when you are crossing an
incline, be sure you, and any 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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If the water is not too deep, drive slowly through it.
At faster speeds, water splashes on the ignition
system and your vehicle can stall. Stalling can also
occur if you get the tailpipe under water. And,
as long as the tailpipe is under water, you will
never be able to start the engine. When you go
through water, remember that when the 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 335
for more information on driving through water.
After Off-Road Driving
Remove any brush or debris that has collected on
the underbody, chassis, or under the hood.
These accumulations can be a re hazard.
After operation in mud or sand, have the brake
linings cleaned and checked. These substances
can cause glazing and uneven braking. Check the
body structure, steering, suspension, wheels, tires,
and exhaust system for damage. Also, check the
fuel lines and cooling system for any leakage.
Your vehicle will require more frequent service
due to off-road use. Refer to the Maintenance
Schedule for additional information.
333

Keep the 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 the 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 the 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.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.
335

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 uid
reservoir 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.
{CAUTION:
Wet brakes can cause accidents. They may
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.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.
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.
336

Before changing lanes, check your mirrors.
Then use your turn signal.
Just before you leave the lane, glance quickly
over your shoulder to make sure there is not
another vehicle in your blind spot.
Once you are moving on the freeway, make
certain you allow a reasonable following distance.
Expect to move slightly slower at night.
When you want to leave the freeway, move to the
proper lane well in advance. If you miss your
exit, do not, under any circumstances, stop and
back up. Drive on to the next exit.
The exit ramp can be curved, sometimes quite
sharply. The exit speed is usually posted.
Reduce your speed according to your
speedometer, not to your sense of motion.
After driving for any distance at higher speeds,
you may tend to think you are going slower than
you actually are.Before Leaving on a Long Trip
Make sure you are ready. Try to be well rested.
If you must start when you are not fresh — such as
after a day’s work — do not plan to make too
many miles that rst part of the journey. Wear
comfortable clothing and shoes you can easily
drive in.
Is your vehicle ready for a long trip? If you keep it
serviced and maintained, it is ready to go. If it
needs service, have it done before starting out.
Of course, you will nd experienced and able
service experts in GM dealerships all across
North America. They will be ready and willing to
help if you need it.
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