GMC SIERRA 2006 Owner's Manual

Before You Go Off-Roading
There are some things to do before you go out. For
example, be sure to have all necessary maintenance and
service work done. Check to make sure all underbody
shields, if equipped, are properly attached. Be sure you
read all the information about your four-wheel-drive
vehicle in this manual. Is there enough fuel? Is the spare
tire fully inated? Are the uid levels up where they
should be? What are the local laws that apply to
off-roading where you will be driving? If you do not know,
you should check with law enforcement people in the
area. Will you be on someone’s private land? If so, be
sure to get the necessary permission.
Loading Your Vehicle for Off-Road
Driving
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.
{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.
You will nd other important information in this manual.
SeeLoading Your Vehicle on page 4-48andTires
on page 5-72.
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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.
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.
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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 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.
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?
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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 are 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 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 4-3.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.
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.
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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.
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).
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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.
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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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Driving Downhill
When off-roading takes you downhill, you will want to
consider a number of things:
How steep is the downhill? Will I be able to maintain
vehicle control?
What is the surface like? Smooth? Rough?
Slippery? Hard-packed dirt? Gravel?
Are there hidden surface obstacles? Ruts? Logs?
Boulders?
What is 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 the brakes and they
will not 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 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), or with the clutch pedal pressed
down with a manual transmission. This is called
“free-wheeling.” The 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 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), or to NEUTRAL with the manual
transmission, 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.
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.
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