tire GMC ENVOY 2005 Owner's Guide

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.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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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
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 5-54.
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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.
Here are some things you can check before a trip:
Windshield Washer Fluid:Is the reservoir full? Are
all windows clean inside and outside?
Wiper Blades:Are they in good shape?
Fuel, Engine Oil, Other Fluids:Have you checked
all levels?
Lamps:Are they all working? Are the lenses clean?
Tires:They are vitally important to a safe,
trouble-free trip. Is the tread good enough for
long-distance driving? Are the tires all inated to the
recommended pressure?
Weather Forecasts:What is the weather outlook
along your route? Should you delay your trip a
short time to avoid a major storm system?
Maps:Do you have up-to-date maps?
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Highway Hypnosis
Is there actually such a condition as highway hypnosis?
Or is it just plain falling asleep at the wheel? Call it
highway hypnosis, lack of awareness, or whatever.
There is something about an easy stretch of road with the
same scenery, along with the hum of the tires on the
road, the drone of the engine, and the rush of the wind
against the vehicle that can make you sleepy. Do not
let it happen to you! If it does, your vehicle can leave the
road in less than a second, and you could crash and
be injured.
What can you do about highway hypnosis? First, be
aware that it can happen.
Then here are some tips:
Make sure your vehicle is well ventilated, with a
comfortably cool interior.
Keep your eyes moving. Scan the road ahead and
to the sides. Check your mirrors and your
instruments frequently.
If you get sleepy, pull off the road into a rest,
service, or parking area and take a nap, get some
exercise, or both. For safety, treat drowsiness
on the highway as an emergency.
Hill and Mountain Roads
Driving on steep hills or mountains is different from
driving in at or rolling terrain.
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If you drive regularly in steep country, or if you are
planning to visit there, here are some tips that can make
your trips safer and more enjoyable. SeeOff-Road
Driving with Your Four-Wheel-Drive Vehicle on
page 4-16for information about driving off-road.
Keep your vehicle in good shape. Check all uid
levels and also the brakes, tires, cooling system,
and transmission. These parts can work hard
on mountain roads.
Know how to go down hills. The most important
thing to know is this: let your engine do some of
the slowing down. Shift to a lower gear when you go
down a steep or long hill.
{CAUTION:
If you do not shift down, your brakes could get
so hot that they would not work well. You
would then have poor braking or even none
going down a hill. You could crash. Shift down
to let your engine assist your brakes on a
steep downhill slope.
{CAUTION:
Coasting downhill in NEUTRAL (N) or with the
ignition off is dangerous. Your brakes will have
to do all the work of slowing down. They could
get so hot that they would not work well. You
would then have poor braking or even none
going down a hill. You could crash. Always have
your engine running and your vehicle in gear
when you go downhill.
Know how to go uphill. You may want to shift down to
a lower gear. The lower gears help cool your engine
and transmission, and you can climb the hill better.
Stay in your own lane when driving on two-lane
roads in hills or mountains. Do not swing wide or cut
across the center of the road. Drive at speeds that let
you stay in your own lane.
As you go over the top of a hill, be alert. There could
be something in your lane, like a stalled car or
an accident.
You may see highway signs on mountains that warn
of special problems. Examples are long grades,
passing or no-passing zones, a falling rocks area,
or winding roads. Be alert to these and take
appropriate action.
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Winter DrivingHere are some tips for winter driving:
Have your vehicle in good shape for winter.
You may want to put winter emergency supplies in
your vehicle.
Also seeTires on page 5-54.
Include an ice scraper, a small brush or broom, a
supply of windshield washer uid, a rag, some winter
outer clothing, a small shovel, a ashlight, a red
cloth, and reective warning triangles. And, if you will be
driving under severe conditions, include a small bag
of sand, a piece of old carpet, or a couple of burlap bags
to help provide traction. Be sure you properly secure
these items in your vehicle.
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Driving on Snow or Ice
Most of the time, those places where your tires meet
the road probably have good traction.
However, if there is snow or ice between your tires and
the road, you can have a very slippery situation. You
will have a lot less traction, or grip, and will need to be
very careful.What is the worst time for this? “Wet ice. Very cold
snow or ice can be slick and hard to drive on. But wet
ice can be even more trouble because it may offer
the least traction of all. You can get wet ice when it is
about freezing (32°F; 0°C) and freezing rain begins
to fall. Try to avoid driving on wet ice until salt and sand
crews can get there.
Whatever the condition — smooth ice, packed, blowing,
or loose snow — drive with caution.
If you have traction assist, it will improve your ability to
accelerate when driving on a slippery road. But you
can turn the traction assist system off if you ever need
to. You should turn the system off if your vehicle
ever gets stuck in sand, mud, ice or snow. SeeIf You
Are Stuck: In Sand, Mud, Ice or Snow on page 4-43.
Even though your vehicle has a traction system, you will
want to slow down and adjust your driving to the road
conditions. Under certain conditions, you may want
to turn the traction assist system off, such as when
driving through deep snow and loose gravel, to help
maintain vehicle motion at lower speeds. SeeTraction
Assist System (TAS) on page 4-9.
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If you do not have a traction system, accelerate gently.
Try not to break the fragile traction. If you accelerate
too fast, the drive wheels will spin and polish the surface
under the tires even more.
Your anti-lock brakes improve your vehicle’s stability
when you make a hard stop on a slippery road.
Even though you have an anti-lock braking system, you
will want to begin stopping sooner than you would on
dry pavement. SeeAnti-Lock Brake System (ABS)
on page 4-7.
Allow greater following distance on any
slippery road.
Watch for slippery spots. The road might be ne
until you hit a spot that is covered with ice. On
an otherwise clear road, ice patches may appear in
shaded areas where the sun cannot reach, such
as around clumps of trees, behind buildings,
or under bridges. Sometimes the surface of a curve
or an overpass may remain icy when the
surrounding roads are clear. If you see a patch of
ice ahead of you, brake before you are on it. Try not
to brake while you are actually on the ice, and
avoid sudden steering maneuvers.
If You Are Caught in a Blizzard
If you are stopped by heavy snow, you could be in a
serious situation. You should probably stay with
your vehicle unless you know for sure that you are near
help and you can hike through the snow. Here are
some things to do to summon help and keep yourself
and your passengers safe:
Turn on your hazard ashers.
Tie a red cloth to your vehicle to alert police that
you have been stopped by the snow.
Put on extra clothing or wrap a blanket around you.
If you do not have blankets or extra clothing, make
body insulators from newspapers, burlap bags,
rags, oor mats — anything you can wrap around
yourself or tuck under your clothing to keep warm.
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Then, shut the engine off and close the window almost all
the way to preserve the heat. Start the engine again and
repeat this only when you feel really uncomfortable from
the cold. But do it as little as possible. Preserve the fuel
as long as you can. To help keep warm, you can get out
of the vehicle and do some fairly vigorous exercises
every half hour or so until help comes.
If You Are Stuck: In Sand, Mud, Ice
or Snow
In order to free your vehicle when it is stuck, you will
need to spin the wheels, but you do not want to
spin your wheels too fast. The method known as rocking
can help you get out when you are stuck, but you
must use caution.
{CAUTION:
If you let your tires spin at high speed, they can
explode, and you or others could be injured.
And, the transmission or other parts of the
vehicle can overheat. That could cause an
engine compartment re or other damage.
When you are stuck, spin the wheels as little as
possible. Do not spin the wheels above 35 mph
(55 km/h) as shown on the speedometer.
Notice:Spinning your wheels can destroy parts of
your vehicle as well as the tires. If you spin the
wheels too fast while shifting your transmission
back and forth, you can destroy your transmission.
For more information about using tire chains on your
vehicle, seeTire Chains on page 5-68.
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Rocking Your Vehicle to Get It Out
First, turn your steering wheel left and right. That
will clear the area around your front wheels. If you have
a four- wheel-drive vehicle, shift into 4HI. Then shift
back and forth between REVERSE (R) and a forward
gear, spinning the wheels as little as possible. Release
the accelerator pedal while you shift, and press lightly
on the accelerator pedal when the transmission is
in gear. By slowly spinning your wheels in the forward
and reverse directions, you will cause a rocking
motion that may free your vehicle. If that does not get
you out after a few tries, you may need to be towed out.
If you do need to be towed out, seeTowing Your
Vehicle on page 4-51.
Loading Your Vehicle
It is very important to know how much weight your
vehicle can carry. This weight is called the vehicle
capacity weight and includes the weight of all occupants,
cargo and all nonfactory-installed options. Two labels
on your vehicle show how much weight it was designed
to carry, the Tire and Loading Information label and
the Certication/Tire label.
{CAUTION:
Do not load your vehicle any heavier than the
Gross Vehicle Weight Rating (GVWR), or either
the maximum front or rear Gross Axle Weight
Rating (GAWR). If you do, parts on your
vehicle can break, and it can change the way
your vehicle handles. These could cause you
to lose control and crash. Also, overloading
can shorten the life of your vehicle.
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