2007 GMC SIERRA CLASSIC Owners Manual

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 — shrubs, owers, trees,
grasses — or disturb wildlife. This includes
wheel-spinning, breaking down trees, or
unnecessary driving through streams or over
soft ground.
Always carry a litter bag — 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 is 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 will
want to know how to use it properly.
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Getting Familiar with Off-Road Driving
It is a good idea to practice in an area that is
safe and close to home before you go into
the wilderness. Off-road driving does require
some new and different driving skills. Here is
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
will need to respond to vibrations and vehicle
bounce.
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 will need more distance for braking,
especially since you are on an unpaved
surface.
{CAUTION:
When you are 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 are driving on or off the road, you and
your passengers should wear safety belts.
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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 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.
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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 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 357.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 cannot do. There are some hills
that simply cannot 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 cannot 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, do not drive the hill.
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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 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 will not have to make turning maneuvers?
Are there obstructions on the hill that can
block your path, such as 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.
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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.
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.
382

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), or shift to
NEUTRAL if your vehicle has a manual
transmission, 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), or pressing the clutch if your
vehicle has a manual transmission, 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.
383

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 the transmission in
PARK (P), or the manual transmission in
FIRST (1), 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) (or, if you have
the manual transmission, even if you are
in gear). 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) (or, put your
manual transmission in FIRST (1)). But do
not shift the transfer case to NEUTRAL.
Leave the transfer case in the Two-Wheel
High, Four-Wheel High or Four-Wheel Low
position.
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