traction control CHEVROLET EXPRESS CARGO VAN 2004 1.G Owners Manual

Cruise Control
If your vehicle has cruise control, you can maintain a
speed of about 25 mph (40 km/h) or more without
keeping your foot on the accelerator. This can really
help on long trips. Cruise control does not work at
speeds below about 25 mph (40 km/h).
If you apply your brakes, the cruise control will
disengage.
{CAUTION:
Cruise control can be dangerous where you
can not drive safely at a steady speed. So, do
not use your cruise control on winding roads
or in heavy traffic.
Cruise control can be dangerous on slippery
roads. On such roads, fast changes in tire
traction can cause needless wheel spinning,
and you could lose control. Do not use cruise
control on slippery roads.
9(Off)This position
turns the system off.
R(On):This position activates the system.
S(Resume/Accelerate):Push the lever to this symbol
to make the vehicle accelerate or resume to a
previously set speed.
T(Set):Press this button to set the speed.
3-11

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 does not 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 will not 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
Do not 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.
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.
4-8

Stabilitrak®System
If your vehicle has Stabilitrak®, it combines antilock
brake, traction and stability control systems and helps
the driver maintain directional control of the vehicle
in most driving conditions.
When you rst start your vehicle and begin to drive
away, the system performs several diagnostic checks to
insure that it is working properly. You may hear or
feel the system working. This is normal and does notmean there is a problem with your vehicle. The system
should initialize before the vehicle reaches 20 mph
(32 km/h). In some cases, it may take approximately two
miles (3.2 km) of driving before the system initializes.
The following chart describes the Stabilitrak
®not ready
light and the Stabilitrak®indicator light.
Stabilitrak®Not Ready Light Stabilitrak®Indicator Light Meaning
Off OffStabilitrak®is enabled,
but not active.
The traction control is not active.
Off FlashingStabilitrak
®is active, or the traction
control is active.
Off OnStabilitrak
®is disabled due to
system fault. When on after
restarting, the vehicle needs
to be serviced.
On OffStabilitrak
®is disabled due to
system initialization or the driver has
disabled with switch.
On FlashingStabilitrak
®is uninitialized
and not disabled.
The traction control is active.
4-9

For more information, seeStabilitrak®Not Ready Light
on page 3-33andStabilitrak®Indicator Light on
page 3-33.
Pressing and holding the
Stabilitrak
®button located
on the instrument panel
for more than ve seconds
can turn off Stabilitrak
®
and part of the traction
control system.
For your safety, the system can only be disabled when
the vehicle speed is less than 20 mph (32 km/h).
You will hear three chimes and the Stabilitrak
®not ready
light will come on.
To turn on the Stabilitrak
®system, press the Stabilitrak®
button again. Stabilitrak®will automatically turn back
on when the vehicle speed exceeds 20 mph (32 km/h).
You will hear one chime and the Stabilitrak
®not
ready light will turn off.
When the Stabilitrak
®system has been turned off you
may still hear system noises as a result of the
brake-traction control coming on.It is recommended to leave the system on for normal
driving conditions, but it may be necessary to turn
the system off if your vehicle is stuck in sand, mud, ice
or snow, and you want to “rock” your vehicle to
attempt to free it. SeeIf You Are Stuck: In Sand, Mud,
Ice or Snow on page 4-31.
Stabilitrak®System Operation
The Stabilitrak®system is normally on, except when the
system is initializing or has been disabled with the
Stabilitrak
®button. The Stabilitrak®system will
automatically activate to assist the driver in maintaining
vehicle directional control in most driving conditions.
When activated, the Stabilitrak
®system may reduce
engine power to the wheels and apply braking to
individual wheels as necessary to assist the driver with
vehicle directional control. If your vehicle is in cruise
control when the system activates, a Stabilitrak
®
indicator light on the instrument panel will ash, and the
cruise control will automatically disengage. When the
Stabilitrak
®system is no longer active, you may
re-engage the cruise control. See “Cruise Control” under
Turn Signal/Multifunction Lever on page 3-8.
The Stabilitrak
®system may also turn off automatically
if it determines that a problem exists with the system.
If the problem does not clear itself after restarting
the vehicle, you should see your dealer for service.
4-10

Traction Control Operation
The traction control system is part of the Stabilitrak®
system. Traction control limits wheel spin by reducing
engine power to the wheels (engine speed
management) and by applying brakes to each individual
wheel (brake-traction control) as necessary.
If the brake-traction control system activates constantly
or if the brakes have heated up due to high speed
braking, the brake-traction control will be automatically
disabled. The system will come back on after the
brakes have cooled. This can take up to two minutes or
longer depending on brake usage.
The traction control system may activate on dry or
rough roads or under conditions such as heavy
acceleration while turning or abrupt upshifts/downshifts
of the transmission. When this happens you may
notice a reduction in acceleration, or may hear a noise
or vibration. This is normal.
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.
4-11

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 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.Driving at Night
Night driving is more dangerous than day driving.
One reason is that some drivers are likely to be
impaired — by alcohol or drugs, with night vision
problems, or by fatigue.
4-16

Buying New Tires
To nd out what kind and size of tires you need, look at
the Certication/Tire label or the Tire and Loading
Information label. For examples of these labels and their
location on your vehicle, seeLoading Your Vehicle on
page 4-33.
The tires installed on your vehicle when it was new had
a Tire Performance Criteria Specication (TPC Spec)
number on each tire’s sidewall. When you get new tires,
General Motors recommends that you get tires with
that same TPC Spec number. That way your vehicle will
continue to have tires that are designed to give proper
endurance, handling, speed rating, load range, traction,
ride and other things during normal service on your
vehicle. If your tires have an all-season tread design, the
TPC number will be followed by an “MS” (for mud
and snow).
If you ever replace your tires with those not having a
TPC Spec number, make sure they are the same size,
load range, speed rating and construction type (bias,
bias-belted or radial) as your original tires.{CAUTION:
Mixing tires could cause you to lose control
while driving. If you mix tires of different sizes
or types (radial and bias-belted tires) the
vehicle may not handle properly, and you
could have a crash. Using tires of different
sizes may also cause damage to your vehicle.
Be sure to use the same size and type tires on
all wheels.
{CAUTION:
If you use bias-ply tires on your vehicle, the
wheel rim anges could develop cracks after
many miles of driving. A tire and/or wheel
could fail suddenly, causing a crash. Use only
radial-ply tires with the wheels on your vehicle.
5-70

Uniform Tire Quality Grading
Quality grades can be found where applicable on the
tire sidewall between tread shoulder and maximum
section width. For example:
Treadwear 200 Traction AA Temperature A
The following information relates to the system
developed by the United States National Highway
Traffic Safety Administration, which grades tires by
treadwear, traction and temperature performance. (This
applies only to vehicles sold in the United States.)
The grades are molded on the sidewalls of most
passenger car tires. The Uniform Tire Quality Grading
system does not apply to deep tread, winter-type
snow tires, space-saver or temporary use spare tires,
tires with nominal rim diameters of 10 to 12 inches
(25 to 30 cm), or to some limited-production tires.
While the tires available on General Motors passenger
cars and light trucks may vary with respect to these
grades, they must also conform to federal safety
requirements and additional General Motors Tire
Performance Criteria (TPC) standards.
Treadwear
The treadwear grade is a comparative rating based on
the wear rate of the tire when tested under controlled
conditions on a specied government test course.
For example, a tire graded 150 would wear one and
a half (1.5) times as well on the government course as
a tire graded 100. The relative performance of tires
depends upon the actual conditions of their use,
however, and may depart signicantly from the norm
due to variations in driving habits, service practices and
differences in road characteristics and climate.
Traction – AA, A, B, C
The traction grades, from highest to lowest, are AA, A,
B, and C. Those grades represent the tire’s ability
to stop on wet pavement as measured under controlled
conditions on specied government test surfaces of
asphalt and concrete. A tire marked C may have poor
traction performance. Warning: The traction grade
assigned to this tire is based on straight-ahead braking
traction tests, and does not include acceleration,
cornering, hydroplaning, or peak traction characteristics.
5-71

Tire Chains
{CAUTION:
If your vehicle has dual wheels or P235/75R16 or
LT245/75R16 size tires, do not use tire chains.
They can damage your vehicle because there’s
not enough clearance. Tire chains used on a
vehicle without the proper amount of clearance
can cause damage to the brakes, suspension or
other vehicle parts. The area damaged by the
tire chains could cause you to lose control of
your vehicle and you or others may be injured
in a crash.
Use another type of traction device only if its
manufacturer recommends it for use on your
vehicle and tire size combination and road
conditions. Follow that manufacturer’s
instructions. To help avoid damage to your
CAUTION: (Continued)
CAUTION: (Continued)
vehicle, drive slowly, readjust or remove the
device if it’s contacting your vehicle, and don’t
spin your wheels.
If you do nd traction devices that will t,
install them on the rear tires.
Notice:If your vehicle does not have dual wheels
and is equipped with a tire size other than
P235/75R16 or LT245/75R16, use tire chains only
where legal and only when you must. Use chains
that are the proper size for your tires. Install them on
the tires of the rear axle. Do not use chains on the
tires of the front axle. Tighten them as tightly as
possible with the ends securely fastened. Drive
slowly and follow the chain manufacturer’s
instructions. If you can hear the chains contacting
your vehicle, stop and retighten them. If the contact
continues, slow down until it stops. Driving too
fast or spinning the wheels with chains on will
damage your vehicle.
5-74

Towing
Recreational Vehicle.....................................4-32
Towing a Trailer..........................................4-38
Your Vehicle...............................................4-32
Traction
Stabilitrak
®System........................................ 4-9
Traction Control Operation................................4-11
Trailer Brakes.................................................4-47
Trailer Wiring Harness.....................................4-51
Transfer Case................................................5-48
Transmission
Fluid, Automatic...........................................5-19
Transmission Operation, Automatic....................2-24
Transmission, Transaxle, Transfer Case Unit
Repair Manual............................................7-12
Transportation Options...................................... 7-8
Trip Odometer................................................3-26
Turn and Lane Change Signals.......................... 3-8
Turn Signal/Multifunction Lever........................... 3-8
Turn Signals When Towing a Trailer..................4-49
U
Understanding Radio Reception........................3-73
Uniform Tire Quality Grading............................5-71
United States – Customer Assistance.................. 7-5
Using Cleaner on Fabric..................................5-93
Using Song List Mode.....................................3-70
V
Vehicle
Control........................................................ 4-5
Damage Warnings........................................... iv
Loading......................................................4-33
Symbols......................................................... iv
Vehicle Data Collection and Event Data
Recorders..................................................7-10
Vehicle Identication
Number (VIN)............................................5-100
Service Parts Identication Label..................5-100
Vehicle Storage..............................................5-42
Ventilation Adjustment......................................3-21
Visor Vanity Mirror..........................................2-18
Visors...........................................................2-18
Voltmeter Gage..............................................3-30
W
Warning Lights, Gages and Indicators................3-24
Warnings
Hazard Warning Flashers............................... 3-6
Other Warning Devices.................................. 3-7
Safety and Symbols......................................... iii
Vehicle Damage.............................................. iv
Washing Your Vehicle......................................5-95
Weight of the Trailer........................................4-40
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