2003 GMC ENVOY And

Environmental Concerns
Off-road driving can provide wholesome and satisfying
recreation. However, it also raises environmental
concerns. We recognize these concerns and urge every
off-roader to follow these basic rules for protecting
the environment:
·Always use established trails, roads and areas that
have been specially set aside for public off-road
recreational driving; obey all posted regulations.
·Avoid any driving practice that could damage
the environment Ð shrubs, ¯owers, trees,
grasses Ð or disturb wildlife (this includes
wheel-spinning, breaking down trees or
unnecessary driving through streams or over soft
ground).
·Always carry a litter bag Ð make sure all refuse is
removed from any campsite before leaving.
·Take extreme care with open ®res (where
permitted), camp stoves and lanterns.
·Never park your vehicle over dry grass or other
combustible materials that could catch ®re from
the heat of the vehicle's exhaust system.
Traveling to Remote Areas
It makes sense to plan your trip, especially when going
to a remote area. Know the terrain and plan your
route. You are much less likely to get bad surprises.
Get accurate maps of trails and terrain. Try to learn of
any blocked or closed roads.
It's also a good idea to travel with at least one other
vehicle. If something happens to one of them, the other
can help quickly.
Does your vehicle have a winch? If so, be sure to read
the winch instructions. In a remote area, a winch
can be handy if you get stuck. But you'll want to know
how to use it properly.
Getting Familiar with Off-Road Driving
It's a good idea to practice in an area that's safe
and close to home before you go into the wilderness.
Off-road driving does require some new and different
skills. Here's what we mean.
Tune your senses to different kinds of signals. Your
eyes, for example, need to constantly sweep the terrain
for unexpected obstacles. Your ears need to listen
for unusual tire or engine sounds. With your arms,
hands, feet and body, you'll need to respond to
vibrations and vehicle bounce.
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Controlling your vehicle is the key to successful off-road
driving. One of the best ways to control your vehicle
is to control your speed. Here are some things to keep
in mind. At higher speeds:
·you approach things faster and you have less time
to scan the terrain for obstacles.
·you have less time to react.
·you have more vehicle bounce when you drive over
obstacles.
·you'll need more distance for braking, especially
since you're on an unpaved surface.
{CAUTION:
When you're driving off-road, bouncing and
quick changes in direction can easily throw
you out of position. This could cause you to
lose control and crash. So, whether you're
driving on or off the road, you and your
passengers should wear safety belts.
Scanning the Terrain
Off-road driving can take you over many different kinds
of terrain. You need to be familiar with the terrain
and its many different features. Here are some things to
consider.
Surface Conditions:Off-roading can take you over
hard-packed dirt, gravel, rocks, grass, sand, mud, snow
or ice. Each of these surfaces affects the steering,
acceleration and braking of your vehicle in different ways.
Depending upon the kind of surface you are on, you may
experience slipping, sliding, wheel spinning, delayed
acceleration, poor traction and longer braking distances.
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?
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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'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 re¯exes, perceptions and judgment can be
affected by even a small amount of alcohol. You
could have a serious Ð or even fatal Ð accident if you
drink and drive or ride with a driver who has been
drinking. See
Drunken Driving on page 4-2.
Driving on Off-Road Hills
Off-road driving often takes you up, down or across a
hill. Driving safely on hills requires good judgment
and an understanding of what your vehicle can and can't
do. There are some hills that simply can't be driven,
no matter how well built the vehicle.
{CAUTION:
Many hills are simply too steep for any vehicle.
If you drive up them, you will stall. If you drive
down them, you can't control your speed. If you
drive across them, you will roll over. You could
be seriously injured or killed. If you have any
doubt about the steepness, don't drive the hill.
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Approaching a Hill
When you approach a hill, you need to decide if it's one
of those hills that's 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 other 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
won't have to make turning maneuvers?
·Are there obstructions on the hill that can block
your path (boulders, trees, logs or ruts)?
·What's beyond the hill? Is there a cliff, an
embankment, a drop-off, a fence? Get out and walk
the hill if you don't know. It's 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. Don't use more power than you
need, because you don't 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're 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 can't 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's what you
shoulddo:
·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 in REVERSE (R).
·If your engine has stopped running, you'll 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'll be able to tell if your wheels
are straight and maneuver as you back down. It's
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 ªrev-upº the engine and regain
forward momentum. This won't 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's steep enough to
cause you to roll over if you turn around. If you can't
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 can't 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. Do not shift the
transfer case to NEUTRAL when you leave
the vehicle. Leave it in some gear.
{CAUTION:
Shifting the transfer case to NEUTRAL can
cause your vehicle to roll even if the
transmission is in PARK (P). This is because
the NEUTRAL position on the transfer case
overrides the transmission. You or someone
else could be injured. If you are going to leave
your vehicle, set the parking brake and shift
the transmission to PARK (P). But do not shift
the transfer case to NEUTRAL. Leave the
transfer case in the 2 Wheel High, 4 High or
4 Low position.
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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?
·Are there hidden surface obstacles? Ruts? Logs?
Boulders?
·What's 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 won't 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'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 ªfree-wheeling.º Your
brakes will have to do all the work and could
overheat and fade.
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Q:Am I likely to stall when going downhill?
A:It's much more likely to happen going uphill. But if
it happens going downhill, here's what to do.
·Stop your vehicle by applying the regular brakes.
Apply the parking brake.
·Shift to PARK (P) and, while still braking, restart the
engine.
·Shift back to a low gear, release the parking brake,
and drive straight down.
·If the engine won't start, get out and get help.
Driving Across an Incline
Sooner or later, an off-road trail will probably go across
the incline of a hill. If this happens, you have to
decide whether to try to drive across the incline. Here
are some things to consider:
·A hill that can be driven straight up or down may be
too steep to drive across. When you go straight up
or down a hill, the length of the wheel base (the
distance from the front wheels to the rear wheels)
reduces the likelihood the vehicle will tumble
end over end. But when you drive across an incline,the much more narrow track width (the distance
between the left and right wheels) may not prevent
the vehicle from tilting and rolling over. Also,
driving across an incline puts more weight on the
downhill wheels. This could cause a downhill
slide or a rollover.
·Surface conditions can be a problem when you
drive across a hill. Loose gravel, muddy spots,
or even wet grass can cause your tires to slip
sideways, downhill. If the vehicle slips sideways, it
can hit something that will trip it (a rock, a rut,
etc.) and roll over.
·Hidden obstacles can make the steepness of the
incline even worse. If you drive across a rock
with the uphill wheels, or if the downhill wheels drop
into a rut or depression, your vehicle can tilt even
more.
For reasons like these, you need to decide carefully
whether to try to drive across an incline. Just because
the trail goes across the incline doesn't mean you
have to drive it. The last vehicle to try it might have
rolled over.
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