2003 GMC SIERRA DIC

means that a woman generally will reach a higher BAC
level than a man of her same body weight will when
each has the same number of drinks.
The law in an increasing number of U.S. states, and
throughout Canada, sets the legal limit at 0.08 percent.
In some other countries, the limit is even lower. For
example, it is 0.05 percent in both France and Germany.
The BAC limit for all commercial drivers in the United
States is 0.04 percent.
The BAC will be over 0.10 percent after three to six
drinks (in one hour). Of course, as we’ve seen, it
depends on how much alcohol is in the drinks, and how
quickly the person drinks them.
But the ability to drive is affected well below a BAC of
0.10 percent. Research shows that the driving skills
of many people are impaired at a BAC approaching
0.05 percent, and that the effects are worse at night.
All drivers are impaired at BAC levels above
0.05 percent. Statistics show that the chance of being in
a collision increases sharply for drivers who have a
BAC of 0.05 percent or above. A driver with a BAC level
of 0.06 percent has doubled his or her chance of
having a collision. At a BAC level of 0.10 percent, the
chance of this driver having a collision is 12 times
greater; at a level of 0.15 percent, the chance is
25 times greater!
The body takes about an hour to rid itself of the alcohol
in one drink. No amount of coffee or number of cold
showers will speed that up.“I’ll be careful”isn’t the rightanswer. What if there’s an emergency, a need to take
sudden action, as when a child darts into the street?
A person with even a moderate BAC might not be able
to react quickly enough to avoid the collision.
There’s something else about drinking and driving that
many people don’t know. Medical research shows
that alcohol in a person’s system can make crash
injuries worse, especially injuries to the brain, spinal
cord or heart. This means that when anyone who
has been drinking—driver or passenger—is in a
crash, that person’s chance of being killed or
permanently disabled is higher than if the person had
not been drinking.
{CAUTION:
Drinking and then driving is very dangerous.
Your reflexes, perceptions, attentiveness and
judgment can be affected by even a small
amount of alcohol.You can have a serious—or
even fatal—collision if you drive after drinking.
Please don’t drink and drive or ride with a
driver who has been drinking.Ride home in a
cab; or if you’re with a group, designate a
driver who will not drink.
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2003 - Sierra Denali

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
rmly 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.
Supplemental Brake Assist System
If your vehicle has vacuum assist power brakes, it is also
equipped with a supplemental brake assist system
that supplies additional vacuum to the vacuum brake
booster if engine vacuum is reduced. Under certain
conditions, the supplemental brake assist system may
run briey after starting your vehicle or when you
apply and release the brake pedal and it may continueto run even after you have removed your foot from the
brake pedal. When the supplemental brake assist
system is operating, you may hear a motor running or
feel a slight vibration in the steering wheel or brake
pedal. This indicates that the supplemental brake assist
system is working to supply additional vacuum for
your vacuum assist power brakes. This is a normal
operation of your brake system and does not require that
the brake system be serviced.
Each time you start your vehicle and accelerate to
10 mph, the supplemental brake assist system
will perform a self-diagnostic check of the system and
you may hear or feel the supplemental brake assist
motor run briey. While you are driving your vehicle, the
supplemental brake assist system monitors itself to
ensure that it is operating properly. If there is a problem
with the supplemental brake assist system, the
SERVICE BRAKE BOOSTER message will be displayed
on the Driver Information Center. SeeDIC Warnings
and Messages on page 3-51.
If your supplemental brake assist system runs every
time you apply and release the brake pedal or you notice
that the brake pedal has suddenly become much
harder to push and the vehicle takes longer to stop, you
should have your vehicle serviced as soon as possible.
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2003 - Sierra Denali

Manual Selectable Ride
The main function of this system is to provide superior
ride comfort while trailering or fully loaded, as well
as for unloaded driving. This system also helps
to provide:
Improved trailering stability
Improved handling response when trailering or fully
loaded
This button is located on
the center of the
instrument panel near the
radio. Press it to activate
the selectable ride
setting as desired.
An indicator light near the
button will illuminate
whenever the system is
active.
It is recommended to use this system as follows:
For optimum ride comfort in an unloaded vehicle
the button should be out and the indicator light
will not be illuminated. This switch 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 illuminated.
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 be off when the
system is in this setting. Use for normal city and highway
driving. Provides a smooth, soft ride when the vehicle
is unloaded.
FIRM (Unloaded):Press the switch to activate this
setting, the indicator light will illuminate. Use this setting
when road conditions or personal preference demand
more control. Provides more“feel″or response to
the road conditions.
FIRM (Loaded):Press the switch to activate this
setting, the indicator light will illuminate. 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.
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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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2003 - Sierra Denali

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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2003 - Sierra Denali

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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2003 - Sierra Denali

You can tow in DRIVE (D). You may want to shift
the transmission to THIRD (3) or, if necessary, a
lower gear selection if the transmission shifts
too often (e.g., under heavy loads and/or hilly
conditions).
Three important considerations have to do with weight:
the weight of the trailer,
the weight of the trailer tongue
and the weight on your vehicle’s tires.
Tow/Haul Mode
Tow/haul is a feature that assists when pulling a heavy
trailer or a large or heavy load. The purpose of the
tow/haul mode is to:
Reduce the frequency and improve the predictability
of transmission shifts when pulling a heavy trailer or
a large or heavy load.
Provide the same solid shift feel when pulling a
heavy trailer or a large or heavy load as when
the vehicle is unloaded.
Improve control of vehicle speed while requiring
less throttle pedal activity when pulling a heavy
trailer or a large or heavy load.
Your vehicle may be equipped with a switch at the end
of the shift lever which when pressed enables
tow/haul. When the switch is pressed, a light on theinstrument panel will illuminate to indicate that tow/haul
has been selected. Tow/haul may be turned off by
pressing the switch again, at which time the indicator
light on the instrument panel will turn off. The vehicle will
automatically turn off tow/haul every time it is started.
Tow/haul is designed to be most effective when the
vehicle and trailer combined weight is at least 75 percent
of the vehicle’s Gross Combined Weight Rating
(GCWR). See Weight of the Trailer later in this section.
Tow/haul is most useful under the following driving
conditions:
When pulling a heavy trailer or a large or heavy
load through rolling terrain.
When pulling a heavy trailer or a large or heavy
load in stop and go traffic.
When pulling a heavy trailer or a large or heavy
load in busy parking lots where improved low
speed control of the vehicle is desired.
Operating the vehicle in tow/haul when lightly loaded or
with no trailer at all will not cause damage. However,
there is no benet to the selection of tow/haul when the
vehicle is unloaded. Such a selection when unloaded
may result in unpleasant engine and transmission driving
characteristics and reduced fuel economy. Tow/haul
is recommended only when pulling a heavy trailer or a
large or heavy load.
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2003 - Sierra Denali