Control of a Vehicle
You have three systems that make your vehicle go
where you want it to go. They are the brakes, the
steering, and the accelerator. All three systems
have to do their work at the places where the tires
meet the road.
Sometimes, as when you are driving on snow or ice,
it is easy to ask more of those control systems than the
tires and road can provide. That means you can lose
control of your vehicle.
Adding non-GM accessories can affect your vehicle’s
performance. SeeAccessories and Modi cations
on page 5-3.
Braking
SeeBrake System Warning Light on page 3-39.
Braking action involves perception time and
reaction time.
First, you have to decide to push on the brake pedal.
That is perception time. Then you have to bring up your
foot and do it. That is reaction time.Average reaction time is about three-fourths of a
second. But that is only an average. It might be less
with one driver and as long as two or three seconds or
more with another. Age, physical condition, alertness,
coordination, and eyesight all play a part. So do alcohol,
drugs, and frustration. But even in three-fourths of a
second, a vehicle moving at 60 mph (100 km/h) travels
66 feet (20 m). That could be a lot of distance in an
emergency, so keeping enough space between
your vehicle and others is important.
And, of course, actual stopping distances vary greatly
with the surface of the road, whether it is pavement
or gravel; the condition of the road, whether it is
wet, dry, or icy; tire tread; the condition of your brakes;
the weight of the vehicle; and the amount of brake
force applied.
4-6
Avoid needless heavy braking. Some people drive
in spurts — heavy acceleration followed by heavy
braking — rather than keeping pace with traffic. This is
a mistake. Your brakes may not have time to cool
between hard stops. Your brakes will wear out much
faster if you do a lot of heavy braking. If you keep pace
with the traffic and allow realistic following distances,
you will eliminate a lot of unnecessary braking.
That means better braking and longer brake life.
If your engine ever stops while you are driving, brake
normally but do not pump your brakes. If you do,
the pedal may get harder to push down. If your engine
stops, you will still have some power brake assist.
But you will use it when you brake. Once the power
assist is used up, it may take longer to stop and
the brake pedal will be harder to push.
Adding non-GM accessories can affect your vehicle’s
performance. SeeAccessories and Modi cations
on page 5-3.Anti-Lock Brake System (ABS)
Your vehicle has the Anti-Lock Brake System (ABS), an
advanced electronic braking system that will help
prevent a braking skid.
When you start your engine and begin to drive away, ABS
will check itself. You may hear a momentary motor or
clicking noise while this test is going on. This is normal.
If there is a problem with
ABS, this warning light will
stay on. SeeAnti-Lock
Brake System Warning
Light on page 3-40.
Along with ABS, your vehicle has a Dynamic Rear
Proportioning (DRP) system. If there is a DRP problem,
both the brake and ABS warning lights will come on
accompanied by a 10-second chime. The lights and
chime will come on each time the ignition is turned on
until the problem is repaired. See your dealer for service.
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Traction control activates when the controller senses
wheel spin. StabiliTrak®will selectively apply the brakes
and reduce engine torque to help regain traction.
Stability control activates when the controller senses a
discrepancy between your intended path and the
direction the vehicle is travelling. StabiliTrak
®selectively
applies braking pressure at any one of the vehicle’s
brakes to help guide the vehicle in the direction which
you are steering.
When you rst start your vehicle and begin to drive
away, the system performs several diagnostic checks to
insure there are no problems. You may hear or feel
the system working. This is normal and does not mean
there is a problem with your vehicle. If driving
conditions delay system initialization, the STABILITRAK
NOT READY message may be displayed. If this is
the case, your vehicle does not need servicing.
For more information on the stability messages, see
DIC Warnings and Messages on page 3-55.When the StabiliTrak
®
system is both on and
actively controlling
the stability of the vehicle,
the StabiliTrak
®light
will blink for the duration of
the event.
You may also feel or hear the system working. This is
normal.
The StabiliTrak
®disable
button is located on the
transmission shift handle.
For vehicles with four-wheel drive, the StabiliTrak
®
system is automatically disabled in 4LO mode
and cannot be turned on until the vehicle is switched to
2HI, 4HI, or 4AWD.
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Vehicles with a DIC Vehicles without a DIC
Event StabiliTrak®
Indicator LightDIC MessageStabiliTrak
®
Indicator LightStabiliTrak
®
Service Light
Blinking StabiliTrak
®Active Blinking OffStabiliTrak
®system
activates using
engine speed
management, brake
traction control,
and/or stability
control.
Solid Service StabiliTrak
®Solid SolidStabiliTrak
®system
is disabled due to a
system fault.
SolidStabiliTrak
®Not
ReadySolid OffStabiliTrak®system
is disabled due to a
failure to initialize.
Notice:If the StabiliTrak
®light comes on due to
heavy braking and/or because the traction control
system has been continuously active, do not
allow the wheel(s) of one axle to spin excessively.
If you do, you may be causing damage to the
transfer case. This could lead to costly repairs not
covered by your warranty.
Notice:If you allow the wheel(s) of one axle to spin
excessively while the StabiliTrak
®, ABS and brake
warning lights and the SERVICE STABILITRAK
message are displayed, you could damage the
transfer case.The repairs would not be covered by your warranty.
Reduce engine power and do not spin the wheel(s)
excessively while these lights and this message
are displayed.
StabiliTrak
®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.
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Hydroplaning
Hydroplaning is dangerous. So much water can build up
under your tires that they can actually ride on the
water. This can happen if the road is wet enough and
you are going fast enough. When your vehicle is
hydroplaning, it has little or no contact with the road.
Hydroplaning does not happen often. But it can if your
tires do not have much tread or if the pressure in
one or more is low. It can happen if a lot of water is
standing on the road. If you can see re ections
from trees, telephone poles, or other vehicles, and
raindrops dimple the water’s surface, there could be
hydroplaning.
Hydroplaning usually happens at higher speeds. There
just is not a hard and fast rule about hydroplaning.
The best advice is to slow down when it is raining.
Driving Through Deep Standing Water
Notice:If you drive too quickly through deep
puddles or standing water, water can come in
through your engine’s air intake and badly damage
your engine. Never drive through water that is
slightly lower than the underbody of your vehicle.
If you cannot avoid deep puddles or standing water,
drive through them very slowly.
Driving Through Flowing Water
{CAUTION:
Flowing or rushing water creates strong
forces. If you try to drive through owing
water, as you might at a low water crossing,
your vehicle can be carried away. As little as
six inches of owing water can carry away a
smaller vehicle. If this happens, you and other
vehicle occupants could drown. Do not ignore
police warning signs, and otherwise be very
cautious about trying to drive through
owing water.
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Here are ways to increase your safety in city driving:
Know the best way to get to where you are
going. Get a city map and plan your trip into
an unknown part of the city just as you would for a
cross-country trip.
Try to use the freeways that rim and crisscross
most large cities. You will save time and energy.
SeeFreeway Driving on page 4-37.
Treat a green light as a warning signal. A traffic
light is there because the corner is busy enough
to need it. When a light turns green, and just before
you start to move, check both ways for vehicles
that have not cleared the intersection or may
be running the red light.
Freeway Driving
Mile for mile, freeways — also called thruways, parkways,
expressways, turnpikes, or superhighways — are the
safest of all roads. But they have their own special rules.
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Winter Driving
Here are some tips for winter driving:
Have your vehicle in good shape for winter.
You may want to put winter emergency supplies
in your vehicle.
Also seeTires on page 5-57.Include an ice scraper, a small brush or broom, a
supply of windshield washer uid, a rag, some winter
outer clothing, a small shovel, a ashlight, a red
cloth, and re ective warning triangles. And, if you will be
driving under severe conditions, include a small bag
of sand, a piece of old carpet, or a couple of burlap bags
to help provide traction. Be sure you properly secure
these items in your vehicle.
Driving on Snow or Ice
Most of the time, those places where the tires meet the
road probably have good traction.
However, if there is snow or ice between the tires and
the road, you can have a very slippery situation. You will
have a lot less traction, or grip, and will need to be
very careful.
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