GMC ENVOY DENALI 2007 Owners Manual

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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Driving in Mud, Sand, Snow, or Ice
When you drive in mud, snow, or sand, the 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, such as on beaches or sand dunes, the 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.
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 the wheel
hubs, axles, or exhaust pipe, do not try it — you
probably will not get through. Also, water that deep
can damage the axle and other vehicle parts.
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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.
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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.
Do not drink and drive.
Adjust the inside rearview mirror to reduce the
glare from headlamps behind you.
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 vehicle’s 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.
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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.
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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 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.
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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
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 439.
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City Driving
One of the biggest problems with city streets is
the amount of traffic on them. You will want
to watch out for what the other drivers are doing
and pay attention to traffic signals.Here are ways to increase your safety in city
driving:
Know the best way to get to where you are
going. Get a city map and plan your trip
into an unknown part of the city just as you
would for a cross-country trip.
Try to use the freeways that rim and crisscross
most large cities. You will save time and
energy. SeeFreeway Driving on page 339.
Treat a green light as a warning signal.
A traffic light is there because the corner
is busy enough to need it. When a light turns
green, and just before you start to move,
check both ways for vehicles that have not
cleared the intersection or may be running the
red light.
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Freeway Driving
Mile for mile, freeways — also called thruways,
parkways, expressways, turnpikes, or
superhighways — are the safest of all roads.
But they have their own special rules.The most important advice on freeway driving is:
Keep up with traffic and keep to the right.
Drive at the same speed most of the other drivers
are driving. Too-fast or too-slow driving breaks
a smooth traffic ow. Treat the left lane on
a freeway as a passing lane.
At the entrance, there is usually a ramp that leads
to the freeway. If you have a clear view of the
freeway as you drive along the entrance ramp, you
should begin to check traffic. Try to determine
where you expect to blend with the ow. Try to
merge into the gap at close to the prevailing speed.
Switch on your turn signal, check your mirrors, and
glance over your shoulder as often as necessary.
Try to blend smoothly with the traffic ow.
Once you are on the freeway, adjust your speed
to the posted limit or to the prevailing rate if it
is slower. Stay in the right lane unless you want
to pass.
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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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