2007 GMC SIERRA Owner's Manual

Steering
Power Steering
If you lose power steering assist because the
engine stops or the system is not functioning, you
can steer but it will take much more effort.
Steering Tips
It is important to take curves at a reasonable
speed.
A lot of the “driver lost control” accidents mentioned
on the news happen on curves. Here is why:
Experienced driver or beginner, each of us is
subject to the same laws of physics when driving on
curves. The traction of the tires against the road
surface makes it possible for the vehicle to change
its path when you turn the front wheels. If there is
no traction, inertia will keep the vehicle going in the
same direction. If you have ever tried to steer a
vehicle on wet ice, you will understand this.
The traction you can get in a curve depends on
the condition of the tires and the road surface, the
angle at which the curve is banked, and your
speed. While you are in a curve, speed is the one
factor you can control.Suppose you are steering through a sharp curve.
Then you suddenly accelerate. Both control
systems — steering and acceleration — have to
do their work where the tires meet the road.
Adding the sudden acceleration can demand too
much of those places. You can lose control.
SeeStabiliTrak
®System on page 381.
What should you do if this ever happens? Ease up
on the accelerator pedal, steer the vehicle the
way you want it to go, and slow down.
Speed limit signs near curves warn that you
should adjust your speed. Of course, the posted
speeds are based on good weather and road
conditions. Under less favorable conditions you will
want to go slower.
If you need to reduce your speed as you approach
a curve, do it before you enter the curve, while
the front wheels are straight ahead.
Try to adjust your speed so you can “drive”
through the curve. Maintain a reasonable, steady
speed. Wait to accelerate until you are out of
the curve, and then accelerate gently into
the straightaway.
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Adding non-GM accessories can affect your
vehicle’s performance. SeeAccessories and
Modications on page 486.
Steering in Emergencies
There are times when steering can be more
effective than braking. For example, you come
over a hill and nd a truck stopped in your lane, or
a car suddenly pulls out from nowhere, or a
child darts out from between parked cars and
stops right in front of you. You can avoid these
problems by braking — if you can stop in time. But
sometimes you cannot; there is not room. That
is the time for evasive action — steering around
the problem.
Your vehicle can perform very well in emergencies
like these. First, apply the brakes. SeeBraking
on page 378. It is better to remove as much speed
as you can from a possible collision. Then steer
around the problem, to the left or right depending
on the space available.An emergency like this requires close attention
and a quick decision. If you are holding the
steering wheel at the recommended 9 and
3 o’clock positions, you can turn it a full
180 degrees very quickly without removing either
hand. But you have to act fast, steer quickly,
and just as quickly straighten the wheel once you
have avoided the object.
The fact that such emergency situations are
always possible is a good reason to practice
defensive driving at all times and wear safety belts
properly.
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Off-Road Recovery
You may nd that your right wheels have dropped
off the edge of a road onto the shoulder while
you are driving.
If the level of the shoulder is only slightly below
the pavement, recovery should be fairly easy.
Ease off the accelerator and then, if there
is nothing in the way, steer so that your vehicle
straddles the edge of the pavement. You can turn
the steering wheel up to one-quarter turn untilthe right front tire contacts the pavement edge.
Then turn the steering wheel to go straight down
the roadway.
Passing
The driver of a vehicle about to pass another on a
two-lane highway waits for just the right moment,
accelerates, moves around the vehicle ahead, then
goes back into the right lane again. A simple
maneuver?
Not necessarily! Passing another vehicle on a
two-lane highway is a potentially dangerous move,
since the passing vehicle occupies the same
lane as oncoming traffic for several seconds. A
miscalculation, an error in judgment, or a
brief surrender to frustration or anger can suddenly
put the passing driver face to face with the
worst of all traffic accidents — the head-on
collision.
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So here are some tips for passing:
Drive ahead. Look down the road, to the
sides, and to crossroads for situations
that might affect your passing patterns. If you
have any doubt whatsoever about making
a successful pass, wait for a better time.
Watch for traffic signs, pavement markings,
and lines. If you can see a sign up ahead
that might indicate a turn or an intersection,
delay your pass. A broken center line
usually indicates it is all right to pass, providing
the road ahead is clear. Never cross a solid
line on your side of the lane or a double solid
line, even if the road seems empty of
approaching traffic.
Do not get too close to the vehicle you want
to pass while you are awaiting an opportunity.
For one thing, following too closely reduces
your area of vision, especially if you are
following a larger vehicle. Also, you will not
have adequate space if the vehicle ahead
suddenly slows or stops. Keep back a
reasonable distance.
When it looks like a chance to pass is coming
up, start to accelerate but stay in the right
lane and do not get too close. Time your moveso you will be increasing speed as the time
comes to move into the other lane. If the way
is clear to pass, you will have a running
start that more than makes up for the distance
you would lose by dropping back. And if
something happens to cause you to cancel
your pass, you need only slow down and drop
back again and wait for another opportunity.
If other vehicles are lined up to pass a slow
vehicle, wait your turn. But take care that
someone is not trying to pass you as you pull
out to pass the slow vehicle. Remember to
glance over your shoulder and check the
blind spot.
Check your vehicle’s mirrors, glance over your
shoulder, and start your left lane change signal
before moving out of the right lane to pass.
When you are far enough ahead of the passed
vehicle to see its front in your vehicle’s inside
mirror, activate the right lane change signal
and move back into the right lane. Remember
that, if your vehicle’s passenger side outside
mirror is convex, the vehicle you just passed
may seem to be farther away from you than it
really is.
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Try not to pass more than one vehicle at a time
on two-lane roads. Reconsider before passing
the next vehicle.
Do not overtake a slowly moving vehicle
too rapidly. Even though the brake lamps are
not ashing, it may be slowing down or starting
to turn.
If you are being passed, make it easy for the
following driver to get ahead of you. Perhaps
you can ease a little to the right.
Loss of Control
Let us review what driving experts say
about what happens when the three
control systems — brakes, steering, and
acceleration — do not have enough friction
where the tires meet the road to do what the
driver has asked.
In any emergency, do not give up. Keep trying to
steer and constantly seek an escape route or
area of less danger.
Skidding
In a skid, a driver can lose control of the vehicle.
Defensive drivers avoid most skids by taking
reasonable care suited to existing conditions, and
by not overdriving those conditions. But skids
are always possible.
The three types of skids correspond to your
vehicle’s three control systems. In the braking skid,
your wheels are not rolling. In the steering or
cornering skid, too much speed or steering in a
curve causes tires to slip and lose cornering force.
And in the acceleration skid, too much throttle
causes the driving wheels to spin.
A cornering skid is best handled by easing your
foot off the accelerator pedal.
Remember: StabiliTrak
®helps avoid only the
acceleration skid. SeeStabiliTrak®System
on page 381. If the StabiliTrak®System is off,
then an acceleration skid is also best handled by
easing your foot off the accelerator pedal.
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If your vehicle starts to slide, ease your foot off
the accelerator pedal and quickly steer the
way you want the vehicle to go. If you start
steering quickly enough, your vehicle may
straighten out. Always be ready for a second skid
if it occurs.
Of course, traction is reduced when water, snow,
ice, gravel, or other material is on the road.
For safety, you will want to slow down and adjust
your driving to these conditions. It is important
to slow down on slippery surfaces because
stopping distance will be longer and vehicle control
more limited.
While driving on a surface with reduced traction, try
your best to avoid sudden steering, acceleration, or
braking, including reducing vehicle speed by
shifting to a lower gear. Any sudden changes could
cause the tires to slide. You may not realize the
surface is slippery until your vehicle is skidding.
Learn to recognize warning clues — such as
enough water, ice, or packed snow on the road to
make a mirrored surface — and slow down when
you have any doubt.
Remember: Any Anti-Lock Brake System (ABS)
helps avoid only the braking skid.Off-Road Driving
This off-road guide is for vehicles that have
four-wheel drive. Also, seeBraking on page 378.If
your vehicle does not have four-wheel drive or
is equipped with 20-inch tire/wheel assemblies,
you should not drive off-road unless you are on a
level, solid surface.
The airbag system is designed to work properly
under a wide range of conditions, including off-road
usage. Observe safe driving speeds, especially
on rough terrain. As always, wear your safety belt.
Off-road driving can be great fun. But it does
have some denite hazards. The greatest of these
is the terrain itself.
“Off-roading” means you have left the great North
American road system behind. Traffic lanes
are not marked. Curves are not banked. There are
no road signs. Surfaces can be slippery, rough,
uphill, or downhill. In short, you have gone
right back to nature.
Off-road driving involves some new skills. And that
is why it is very important that you read this
guide. You will nd many driving tips and
suggestions. These will help make your off-road
driving safer and more enjoyable.
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If you think you will need some more ground
clearance at the front of your vehicle, you
can remove the front fascia lower air dam.
The front fascia lower air dam is held in place by
two bolts and 10 snap features. The bolts and
snap features are accessible from underneath the
front fascia.
The following steps must be performed on the
bolts and snap features to remove the air dam:
1. Remove the two outboard air dam bolts.
2. With a at-blade screwdriver, push down on
the snap features and disengage the snaps.
3. After the bolts are removed and the snaps are
disengaged, push forward on the air dam until
it is free.
When you are back on roads, though, be sure to
replace the air dam.
Notice:Operating your vehicle for extended
periods without the front fascia lower air
dam installed can cause improper air ow to
the engine. Always be sure to replace the front
fascia air dam when you are nished off-road
driving.To reinstall the lower air dam do the following:
1. Line up the snap features and push the
air dam rearward to engage the snaps.
2. Install the two outboard bolts.
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 the vehicle has
them, 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.
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Loading Your Vehicle for Off-Road
Driving
{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.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.
You will nd other important information in this
manual. SeeLoading Your Vehicle on page 425
andTires on page 550.
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