2005 GMC SIERRA Owner's Manual

It is recommended to use this system as follows:
For optimum ride comfort in an unloaded vehicle
the button should be out. The indicator light will
not be lit. This button position indicates NORMAL
levels of ride control or damping.
For optimum ride comfort when trailering, fully
loaded, driving off-road, or when personal
preferences demand more control, the button
should be pressed in with the indicator light lit.
This switch position indicates FIRM levels of ride
control or damping.
The following guide can also be used to help determine
the best setting.
NORMAL:The indicator light will not be lit when the
system is in this setting. Use for normal city and highway
driving. This setting provides a smooth, soft ride when
the vehicle is unloaded.
FIRM (Unloaded):Press the button to activate this
setting, the indicator light will be lit. Use this setting
when road conditions or personal preference demand
more control. This setting provides more “feel” or
response to the road conditions.FIRM (Loaded):Press the button to activate this
setting, the indicator light will be lit. Use this setting to
minimize trailer inputs to the vehicle or when the vehicle
is fully loaded. This setting is also appropriate for
off-road driving.
You can select a setting at any time based on road and
trailering conditions to provide the best ride and
handling. Select a new setting whenever driving
conditions change.
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 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 your 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. SeeTraction Assist
System (TAS) on page 4-8.
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 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.
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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 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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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:
2:Two-wheel steering
4:Four-wheel steering
_:Four-wheel steering with a trailer modeThe 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 steer mode 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 ashing, you will have to center the
steering wheel by turning it to the left or right.
Your vehicle will return to 2 when the transmission is
shifted into NEUTRAL (N), for example when entering a
car wash.
If you want to use tire chains, the vehicle needs to be in
2-wheel steer mode. For more information seeTire
Chains on page 5-90.
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4:In this mode, all four wheels will help steer the
vehicle. If you want to use 4, 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, comes
on and stays on. If the 4 indicator is ashing, 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.
Slower Speeds (below 40 mph (64 km/h))
Higher Speeds (40 mph (64 km/h), and above)
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_(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
button until the 4 and tow mode 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 4-68.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.
A. 13 inches (33 cm)
B. 82 inches (208 cm)
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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 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 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.
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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 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 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 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.
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.
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