2003 GMC SIERRA Owner's Manual

Steering in Emergencies
There are times when steering can be more effective
than braking. For example, you come over a hill andnd
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.
Your vehicle can perform very well in emergencies like
these. First apply your brakes.
SeeBraking on page 4-5. 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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2003 - Sierra Denali

QUADRASTEER™
The QUADRASTEER™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 (_)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
isashing 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.
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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 isashing you will
have to center the steering wheel by turning it to the left
or right.
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.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. Slower Speeds (below 40 m.p.h./64 km/h)
Higher Speeds (40 m.p.h./64 km/h and above)
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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
ashing 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, seeTowing a
Trailer on page 4-53.
Car Washes for
QUADRASTEER™ 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.
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2003 - Sierra Denali

Off-Road Recovery
You maynd that your right wheels have dropped off
the edge of a road onto the shoulder while you’re
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 until the right front tire contacts
the pavement edge. Then turn your 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.
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.
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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.
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 frontin 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 notashing, 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.
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2003 - Sierra Denali

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.
While driving on a surface with reduced traction, try
your best to avoid sudden steering, acceleration
or braking (including engine braking 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.
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Operating Your All-Wheel-Drive
Vehicle Off Paved Roads
Many of the same design features that help make your
vehicle responsive on paved roads during poor
weather conditions—features like the locking rear axle
and all-wheel drive—help make it much better
suited for off-road use than a conventional passenger
car. Its higher ground clearance also helps your vehicle
step over some off-road obstacles. But your vehicle
doesn’t have features like special underbody shielding
and a transfer case low gear range, things that are
usually thought necessary for extended or severe
off-road service. This guide is for operating your vehicle
off paved roads.
Also, seeBraking on page 4-5.
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’ve left the great North American
road system behind. Traffic lanes aren’t marked.
Curves aren’t banked. There are no road signs.
Surfaces can be slippery, rough, uphill or downhill.
In short, you’ve gone right back to nature.Off-road driving involves some new skills. And that’s
why it’s very important that you read this guide.
You’llnd many driving tips and suggestions. These will
help make your off-road driving safer and more
enjoyable.
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 so equipped) are properly
attached. Is there enough fuel? Is the spare tire fully
inated? Are theuid levels up where they should be?
What are the local laws that apply to off-roading
where you’ll be driving? If you don’t 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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