brakes BUICK LACROSSE 2009 User Guide

Antilock Brake System (ABS)
This vehicle has the Antilock Brake System (ABS), an
advanced electronic braking system that will help
prevent a braking skid.
When the engine is started and the vehicle begins to
drive away, ABS checks itself. A momentary motor
or clicking noise might be heard while this test is going
on, and it might even be noticed that the brake pedal
moves a little. This is normal.
If there is a problem with
ABS, this warning light
stays on. SeeAntilock
Brake System (ABS)
Warning Light on
page 3-36.
Let us say the road is wet and you are driving safely.
Suddenly, an animal jumps out in front of you. You slam
on the brakes and continue braking. Here is what
happens with ABS:
A computer senses that the wheels are slowing down. If
one of the wheels is about to stop rolling, the computer
will separately work the brakes at each wheel.ABS can change the brake pressure to each wheel, as
required, faster than any driver could. This can help
the driver steer around the obstacle while braking hard.
As the brakes are applied, the computer keeps receiving
updates on wheel speed and controls braking pressure
accordingly.
Remember: ABS does not change the time needed to get
a foot up to the brake pedal or always decrease stopping
distance. If you get too close to the vehicle in front of you,
there will not be enough time to apply the brakes if that
vehicle suddenly slows or stops. Always leave enough
room up ahead to stop, even with ABS.
Using ABS
Do not pump the brakes. Just hold the brake pedal
down rmly and let antilock work. The antilock pump or
motor might be heard operating and the brake pedal
might be felt to pulsate, but this is normal.
Braking in Emergencies
ABS allows the driver to steer and brake at the same
time. In many emergencies, steering can help more than
even the very best braking.
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StabiliTrak®System
The vehicle may be equipped with a vehicle stability
enhancement system called StabiliTrak. It is an
advanced computer controlled system that assists with
directional control of the vehicle in difficult driving
conditions.
StabiliTrak activates when the computer senses a
discrepancy between the intended path and the direction
the vehicle is actually traveling. StabiliTrak selectively
applies braking pressure at any one of the vehicle’s
brakes to assist the driver with keeping the vehicle on
the intended path.
When the system activates, STABILITY CONTROL
ACTIVE comes on the Driver Information Center (DIC).
SeeDIC Warnings and Messages on page 3-56.
The system may be heard or felt while it is working.
This is normal. Continue to steer the vehicle in the
intended direction.The Traction Control
warning light comes on the
instrument panel cluster
when a problem is
detected with StabiliTrak.
If there is a problem detected with StabiliTrak, a
SERVICE STABILITY SYSTEM or STABILITY
CONTROL OFF message will be displayed on the DIC.
When this message is displayed, the system is not
operational. Driving should be adjusted accordingly.
If cruise control is being used when StabiliTrak activates,
the cruise control automatically disengages. The
cruise control can be reengaged when road conditions
allow. SeeCruise Control on page 3-10for more
information.
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For vehicles with the 5.3L V8 engine, StabiliTrak can be
turned off by pressing and holding the traction control
button, located above the radio, for approximately
ve seconds. A STABILITY CONTROL OFF message
will be displayed on the DIC when StabiliTrak is
turned off. StabiliTrak will remain off until the traction
control button is pressed once to turn it back on, or until
the engine is restarted.
Traction Control System (TCS)
The vehicle may have a Traction Control System (TCS)
that limits wheel spin. This is especially useful in
slippery road conditions. The system operates only if it
senses that one or both of the front wheels are
spinning or beginning to lose traction. When this
happens, the system works the front brakes and reduces
engine power to limit wheel spin. It may also upshift
the transmission to limit wheel spin. The system may be
heard or felt while it is working, but this is normal.
The TRACTION CONTROL ACTIVE message on the
Driver Information Center (DIC) will be displayed
when the system is limiting wheel spin.
If cruise control is being used when TCS begins to limit
wheel spin, the cruise control automatically disengages.
The cruise control can be re-engaged when road
conditions allow. SeeCruise Control on page 3-10.
TCS operates in all transmission shift lever positions.
But the system can upshift the transmission only as high
as the shift lever position that was chosen, so use the
lower gears only when necessary. SeeAutomatic
Transmission Operation on page 2-26.
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Steering
Power Steering
If power steering assist is lost because the engine stops
or the system is not functioning, the vehicle can be
steered but it will take more effort.
Steering Tips
It is important to take curves at a reasonable speed.
Traction in a curve depends on the condition of the tires
and the road surface, the angle at which the curve is
banked, and vehicle speed. While in a curve, speed is
the one factor that can be controlled.
If there is a need to reduce speed, do it before entering
the curve, while the front wheels are straight.
Try to adjust the speed so you can drive through the
curve. Maintain a reasonable, steady speed. Wait
to accelerate until out of the curve, and then accelerate
gently into the straightaway.
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. These problems can
be avoided by braking — if you can stop in time. But
sometimes you cannot stop in time because there is no
room. That is the time for evasive action — steering
around the problem.
The vehicle can perform very well in emergencies like
these. First apply the brakes. SeeBraking on page 4-4.
It is better to remove as much speed as possible
from a collision. Then steer around the problem, to the
left or right depending on the space available.
4-10

Passing
Passing another vehicle on a two-lane road can be
dangerous. To reduce the risk of danger while passing:
Look down the road, to the sides, and to crossroads
for situations that might affect a successful pass. If
in doubt, wait.
Watch for traffic signs, pavement markings, and
lines that could indicate a turn or an intersection.
Never cross a solid or double-solid line on your side
of the lane.
Do not get too close to the vehicle you want to
pass. Doing so can reduce your visibility.
Wait your turn to pass a slow vehicle.
When you are being passed, ease to the right.
Loss of Control
Let us review what driving experts say about what
happens when the three control systems — brakes,
steering, and acceleration — do not have enough friction
where the tires meet the road to do what the driver has
asked.
In any emergency, do not give up. Keep trying to steer
and constantly seek an escape route or area of less
danger.
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 the vehicle’s
three control systems. In the braking skid, the wheels
are not 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.
Remember: Any traction control system helps avoid only
the acceleration skid. If the traction control system is
off, then an acceleration skid is best handled by easing
your foot off the accelerator pedal.
If the 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,
the 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, 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.
4-12

Driving in Rain and on Wet Roads
Rain and wet roads can reduce vehicle traction
and affect your ability to stop and accelerate. Always
drive slower in these types of driving conditions
and avoid driving through large puddles and
deep-standing or owing water.
{CAUTION:
Wet brakes can cause crashes. They might not
work as well in a quick stop and could cause
pulling to one side. You could lose control of the
vehicle.
After driving through a large puddle of water or a
car/vehicle wash, lightly apply the brake pedal until
the brakes work normally.
Flowing or rushing water creates strong forces.
Driving through owing water could cause your
vehicle to be carried away. If this happens, you
and other vehicle occupants could drown. Do not
ignore police warnings and be very cautious about
trying to drive through owing water.
Hydroplaning
Hydroplaning is dangerous. Water can build up under
your vehicle’s tires so they 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.
There is no hard and fast rule about hydroplaning. The
best advice is to slow down when the road is wet.
Other Rainy Weather Tips
Besides slowing down, other wet weather driving tips
include:
Allow extra following distance.
Pass with caution.
Keep windshield wiping equipment in good shape.
Keep the windshield washer uid reservoir lled.
Have good tires with proper tread depth. SeeTires
on page 5-54.
Turn off cruise control.
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Hill and Mountain Roads
Driving on steep hills or through mountains is different
than driving on at or rolling terrain. Tips for driving
in these conditions include:
Keep the vehicle serviced and in good shape.
Check all uid levels and brakes, tires, cooling
system, and transmission.
Going down steep or long hills, shift to a
lower gear.
{CAUTION:
If you do not shift down, the brakes could get so
hot that they would not work well. You would then
have poor braking or even none going down a hill.
You could crash. Shift down to let the engine
assist the brakes on a steep downhill slope.
{CAUTION:
Coasting downhill in N (Neutral) or with the ignition
off is dangerous. The brakes will have to do all the
work of slowing down and they could get so hot
that they would not work well. You would then
have poor braking or even none going down a hill.
You could crash. Always have the engine running
and the vehicle in gear when going downhill.
Stay in your own lane. Do not swing wide or cut
across the center of the road. Drive at speeds
that let you stay in your own lane.
Top of hills: Be alert — something could be in your
lane (stalled car, accident).
Pay attention to special road signs (falling rocks
area, winding roads, long grades, passing or
no-passing zones) and take appropriate action.
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Winter Driving
Driving on Snow or Ice
Drive carefully when there is snow or ice between the
tires and the road, creating less traction or grip. Wet ice
can occur at about 32°F (0°C) when freezing rain
begins to fall, resulting in even less traction. Avoid
driving on wet ice or in freezing rain until roads can be
treated with salt or sand.
Drive with caution, whatever the condition. Accelerate
gently so traction is not lost. Accelerating too quickly
causes the wheels to spin and makes the surface under
the tires slick, so there is even less traction.
Try not to break the fragile traction. If you accelerate too
fast, the drive wheels will spin and polish the surface
under the tires even more.If the vehicle has theTraction Control System (TCS) on
page 4-7orEnhanced Traction System (ETS) on
page 4-8, it improves the ability to accelerate on slippery
roads, but slow down and adjust your driving to the
road conditions. When driving through deep snow, turn
off the traction system to help maintain vehicle motion
at lower speeds.
TheAntilock Brake System (ABS) on page 4-5improves
vehicle stability during hard stops on a slippery roads, but
apply the brakes sooner than when on dry pavement.
Allow greater following distance on any slippery road
and watch for slippery spots. Icy patches can occur on
otherwise clear roads in shaded areas. The surface
of a curve or an overpass can remain icy when
the surrounding roads are clear. Avoid sudden steering
maneuvers and braking while on ice.
Turn off cruise control, if equipped, on slippery surfaces.
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6. Remove the key from the ignition.
7. Secure the vehicle to the dolly following the
manufacturer’s instructions.
8. Release the parking brake only after the vehicle
being towed is rmly attached to the dolly.
Towing a Trailer
{CAUTION:
The driver can lose control when pulling a trailer if
the correct equipment is not used or the vehicle is
not driven properly. For example, if the trailer is
too heavy, the brakes may not work well — or
even at all. The driver and passengers could be
seriously injured. The vehicle may also be
damaged; the resulting repairs would not be
covered by the vehicle warranty. Pull a trailer only
if all the steps in this section have been followed.
Ask your dealer/retailer for advice and information
about towing a trailer with the vehicle.Notice:Pulling a trailer improperly can damage the
vehicle and result in costly repairs not covered
by the vehicle warranty. To pull a trailer correctly,
follow the advice in this section and see your
dealer/retailer for important information about
towing a trailer with the vehicle.
The vehicle can tow a trailer if it is equipped with the
proper trailer towing equipment. To identify the trailering
capacity of the vehicle, read the information in “Weight
of the Trailer” that appears later in this section. Trailering
is different than just driving the vehicle by itself.
Trailering means changes in handling, acceleration,
braking, durability and fuel economy. Successful, safe
trailering takes correct equipment, and it has to be used
properly.
The following information has many time-tested,
important trailering tips and safety rules. Many of these
are important for the safety of the driver and the
passengers. So please read this section carefully before
pulling a trailer.
Load-pulling components such as the engine,
transmission, axles, wheel assemblies and tires are
forced to work harder against the drag of the added
weight. The engine is required to operate at relatively
higher speeds and under greater loads, generating extra
heat. The trailer also adds considerably to wind
resistance, increasing the pulling requirements.
4-28

Hitches
It is important to have the correct hitch equipment.
Crosswinds, large trucks going by and rough roads are
a few reasons why the right hitch is needed. Here
are some rules to follow:
The rear bumper on the vehicle is not intended
for hitches. Do not attach rental hitches or
other bumper-type hitches to it. Use only a
frame-mounted hitch that does not attach to the
bumper.
Will any holes be made in the body of the vehicle
when the trailer hitch is installed? If there are,
then be sure to seal the holes later when the hitch
is removed. If the holes are not sealed, dirt,
water, and deadly carbon monoxide (CO) from the
exhaust can get into the vehicle. SeeEngine
Exhaust on page 2-33in the Index for more
information.
Safety Chains
Always attach chains between the vehicle and the
trailer. Cross the safety chains under the tongue of the
trailer to help prevent the tongue from contacting
the road if it becomes separated from the hitch.
Instructions about safety chains may be provided by the
hitch manufacturer or by the trailer manufacturer.
Follow the manufacturer’s recommendation for attaching
safety chains and do not attach them to the bumper.
Always leave just enough slack so the rig can turn.
Never allow safety chains to drag on the ground.
Trailer Brakes
Because the vehicle has antilock brakes, do not try to
tap into the vehicle’s hydraulic brake system. If you
do, both brake systems will not work well, or at all.
Does your trailer have its own brakes? Be sure to read
and follow the instructions for the trailer brakes so
you will be able to install, adjust and maintain them
properly.
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