2003 GMC SIERRA DENALI Owners Manual

The anti-lock system can change the brake pressure
faster than any driver could. The computer is
programmed to make the most
of available tire and road
conditions. This can help you steer around the obstacle
while braking hard.
As you brake, your computer keeps receiving updates
on wheel speed and controls braking pressure
accordingly. Remember:
Anti-lock doesn’t change the time you need
to get your foot up
to the brake pedal or always
decrease stopping distance.
If you get too close to the
vehicle in front of you, you won’t have time to apply
your brakes
if that vehicle suddenly slows or stops.
Always leave enough room up ahead
to stop, even
though you have anti-lock brakes.
Using Anti-Lock
Don’t pump the brakes. Just hold the brake pedal down
firmly and let anti-lock work for you. You may feel
the brakes vibrate, or you may notice some noise, but
this is normal.
Braking in Emergencies
With anti-lock, you can steer and brake at the same
time. In many emergencies, steering can help you more
than even the very best braking.
Locking Rear Axle
If your vehicle has this feature, your locking rear axle
can give you additional traction on snow, mud, ice, sand
or gravel. It works like a standard axle most of the
time, but when one of the rear wheels has no traction
and the other does, this feature will allow the wheel with
traction to move the vehicle.
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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
Driving on Curves
It’s important to take curves at a reasonable speed.
A lot of the “driver lost control” accidents mentioned on
the news happen on curves. Here’s 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’s no traction, inertia
will keep the vehicle going in the same direction.
If
you’ve ever tried to steer a vehicle on wet ice, you’ll
understand this.
The traction you can get in a curve depends on the
condition of your tires and the road surface, the angle at
which the curve is banked, and your speed. While you’re
in a curve, speed
is the one factor you can control. Suppose
you’re 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.
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’ll want to go slower.
If you need to reduce your speed as you approach a
curve, do it before you enter the curve, while your 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.
Steering in Emergencies
There are times when steering can be more effective than
braking. For example, you come over a hill and find 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 can’t; there isn’t room. That’s the time for
evasive action
- steering around the problem.
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Your vehicle can perform very well in emergencies like
these. First apply your brakes.
See
Braking on page 4-6. 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.
QUADRASTEERTM
The QUADRASTEERTM System has a control and
diagnostic module that monitors and records current
system status and operational information.
If your vehicle is equipped with the 4 Wheel Steer
system it has the ability to steer the vehicle with all four
wheels.
Once the
4 Wheel Steer mode is selected, it is
recommended
to leave the vehicle in this mode at all
times, and during all driving and weather conditions.
You can select this mode at any speed, however,
if you
are turning the system will not engage until the turn
is complete.
The 4 Wheel Steer system is equipped with three
different driving modes:
Two wheel steering (2)
Four wheel steering (4)
Four wheel steering with a trailer mode (q )
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The switch is located on the instrument panel.
2: In this mode the vehicle will operate like any other
vehicle with two wheel steering. If you want to use
2 wheel steering and your vehicle is not in this mode,
press the button until the
2 indicator, located to the right
of the
4 Wheel Steer button, lights up. If the 2 indicator
is flashing you will have to center the steering wheel
by turning it
to the left or right.
Your vehicle will return to
2 (two wheel steering) when
the transmission is shifted into NEUTRAL, for
example when entering a car wash.
4: In this mode all four wheels will help steer the
vehicle.
If you want to use 4 wheel steering, and your
vehicle is not in this mode, press the button, until
the
4 indicator, located to the right of the 4 Wheel Steer
button, lights up.
If the 4 indicator is flashing you will
have to center the steering wheel by turning it to the left
or right.
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Slower Speeds (below 40 m.p.h./64 km/h)
At slower speeds the front and rear wheels will turn in
opposite directions. This helps the vehicle make
tighter turns, such as during parking, cornering and
turning into tight spaces.
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Higher Speeds (40 m.p.h./64 km/h and above)
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At higher speeds the front and rear wheels will turn in
the same direction. This improves stability of the vehicle
during lane changes and sweeping turns.
(4 Wheel Steer tow mode): When towing a trailer
the
4 wheel steer tow mode provides enhanced
stability allowing the trailer to follow the path of the tow
vehicle more closely, especially during lane changes.
In this mode the system operates much like the
4 mode,
but is enhanced for trailer towing. It is recommended
for all types and weights
of trailers.
To engage the
4 wheel steer tow mode, press the 4
Wheel Steer button until the 4 and tow indicators light up
on the instrument panel.
If the tow indicator is flashing
you will have to center the steering wheel by turning it to
the left or right. While in the
4 wheel steer tow mode,
it is possible the steering wheel may be slightly
off
center. For more information, see Towing a Trailer on
page
4-5 I.
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Car Washes for
QUADRASTEERTM Equipped Vehicles
Notice: Because your vehicle has a wider rear track
a small number
of older car washes may be too
narrow for your vehicle. Conveyor systems on some
automatic car washes may damage your vehicle.
Only use conveyor system car washes with 13-inch
(33 cm) wide conveyor rails and/or stationary
washes with at least 82 inches (208 cm) between the
rails. Before using the car wash check with the
manager.
13 in. 13 in.
(33 cm) (33 . 1. cm)
Off -Road Recovery
You may find that your right wheels have dropped off
the edge of a road onto the shoulder while you’re
driving.
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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 until the right front tire contacts
the pavement edge, Then turn your steering wheel to go
straight down the roadway.
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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.
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’s 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’re awaiting an opportunity. For
one thing, following too closely reduces your area
of vision, especially
if you’re following a larger
vehicle. Also, you won’t 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 don’t
get too close. Time your move
so 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 isn’t trying
to pass you as you pull out to pass the slow vehicle.
Remember to glance over your shoulder and check
the blind spot.
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Check your 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
inside mirror, activate your right lane change signal
and move back into the right lane. (Remember that
if
your right outside mirror is convex, the vehicle you
just passed may seem
to be farther away from you
than it really is.)
Try not to pass more than one vehicle at a time on
two-lane roads. Reconsider before passing the next
vehicle.
Don’t overtake a slowly moving vehicle too rapidly.
Even though the brake lamps are not flashing, it may
be slowing down or starting to turn.
If you’re 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’s review what driving experts say about what
happens when the three control systems (brakes,
steering and acceleration) don’t have enough friction
where the tires meet the road to do what the driver
has asked.
In any emergency, don’t 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
aren’t 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.
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’ll
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.
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