2006 BUICK LACROSSE Owner's Manual

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.
Temperature – A, B, C
The temperature grades are A (the highest), B, and C,
representing the tire’s resistance to the generation
of heat and its ability to dissipate heat when tested
under controlled conditions on a specied indoor
laboratory test wheel. Sustained high temperature
can cause the material of the tire to degenerate and
reduce tire life, and excessive temperature can lead
to sudden tire failure. The grade C corresponds to
a level of performance which all passenger car tires
must meet under the Federal Motor Vehicle Safety
Standard No. 109. Grades B and A represent higher
levels of performance on the laboratory test wheel
than the minimum required by law.
Warning:The temperature grade for this tire is
established for a tire that is properly inated and
not overloaded. Excessive speed, underination, or
excessive loading, either separately or in combination,
can cause heat buildup and possible tire failure.
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Wheel Alignment and Tire Balance
The tires and wheels on your vehicle were aligned
and balanced carefully at the factory to give you
the longest tire life and best overall performance.
Adjustments to wheel alignment and tire balancing
will not be necessary on a regular basis. However,
if you notice unusual tire wear or your vehicle pulling
to one side or the other, the alignment may need to
be checked. If you notice your vehicle vibrating when
driving on a smooth road, your tires and wheels
may need to be rebalanced. See your dealer for
proper diagnosis.
Wheel Replacement
Replace any wheel that is bent, cracked, or badly rusted
or corroded. If wheel nuts keep coming loose, the wheel,
wheel bolts, and wheel nuts should be replaced. If the
wheel leaks air, replace it (except some aluminum
wheels, which can sometimes be repaired). See your
dealer if any of these conditions exist.
Your dealer will know the kind of wheel you need.
Each new wheel should have the same load-carrying
capacity, diameter, width, offset and be mounted
the same way as the one it replaces.
If you need to replace any of your wheels, wheel
bolts, or wheel nuts, replace them only with new GM
original equipment parts. This way, you will be sure
to have the right wheel, wheel bolts, and wheel nuts
for your vehicle.
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{CAUTION:
Using the wrong replacement wheels, wheel
bolts, or wheel nuts on your vehicle can be
dangerous. It could affect the braking and
handling of your vehicle, make your tires
lose air and make you lose control. You could
have a collision in which you or others could
be injured. Always use the correct wheel,
wheel bolts, and wheel nuts for replacement.
Notice:The wrong wheel can also cause problems
with bearing life, brake cooling, speedometer or
odometer calibration, headlamp aim, bumper height,
vehicle ground clearance, and tire or tire chain
clearance to the body and chassis.
SeeChanging a Flat Tire on page 5-73for more
information.
Used Replacement Wheels
{CAUTION:
Putting a used wheel on your vehicle is
dangerous. You cannot know how it has been
used or how far it has been driven. It could
fail suddenly and cause a crash. If you have
to replace a wheel, use a new GM original
equipment wheel.
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Tire Chains
{CAUTION:
If your vehicle has P225/55R17 size tires,
do not use tire chains, there is 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
vehicle, drive slowly, readjust or remove the
device if it is contacting your vehicle, and do
not spin your wheels.
If you do nd traction devices that will t,
install them on the front tires.Notice:If your vehicle has a tire size other than
P225/55R17 size tires, use tire chains only where
legal and only when you must. Use only SAE Class
“S” type chains that are the proper size for your
tires. Install them on the front tires and 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.
If a Tire Goes Flat
It is unusual for a tire to blowout while you are driving,
especially if you maintain your vehicle’s tires properly.
If air goes out of a tire, it is much more likely to leak
out slowly. But if you should ever have a blowout, here
are a few tips about what to expect and what to do:
If a front tire fails, the at tire will create a drag that
pulls the vehicle toward that side. Take your foot off the
accelerator pedal and grip the steering wheel rmly.
Steer to maintain lane position, and then gently brake
to a stop well out of the traffic lane.
A rear blowout, particularly on a curve, acts much
like a skid and may require the same correction you
would use in a skid. In any rear blowout remove
your foot from the accelerator pedal.
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Get the vehicle under control by steering the way you
want the vehicle to go. It may be very bumpy and noisy,
but you can still steer. Gently brake to a stop, well off
the road if possible.
{CAUTION:
Lifting a vehicle and getting under it to do
maintenance or repairs is dangerous without
the appropriate safety equipment and training.
The jack provided with your vehicle is designed
only for changing a at tire. If it is used for
anything else, you or others could be badly
injured or killed if the vehicle slips off the jack.
Use the jack provided with your vehicle only for
changing a at tire.
If a tire goes at, the next part shows how to use the
jacking equipment to change a at tire safely.
Changing a Flat Tire
If a tire goes at, avoid further tire and wheel damage
by driving slowly to a level place. Turn on your vehicle’s
hazard warning ashers. SeeHazard Warning Flashers
on page 3-6for more information.
{CAUTION:
Changing a tire can be dangerous. The vehicle
can slip off the jack and roll over or fall on you
or other people. You and they could be badly
injured or even killed. Find a level place to
change your tire. To help prevent the vehicle
from moving:
1. Set the parking brake rmly.
2. Put the shift lever in PARK (P).
3. Turn off the engine and do not restart
while the vehicle is raised.
4. Do not allow passengers to remain in
the vehicle.
To be even more certain the vehicle will not
move, you should put blocks at the front and
rear of the tire farthest away from the one
being changed. That would be the tire, on the
other side, at the opposite end of the vehicle.
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When your vehicle has a at tire, use the following
example as a guide to assist you in the placement of
wheel blocks.
The following information will tell you next how to use
the jack and change a tire.Removing the Spare Tire and Tools
The equipment you will need is located in the trunk.
1. Open the trunk. SeeTrunk on page 2-13for more
information.
2. Remove the convenience net if the vehicle has one.
3. Lift the handle on the spare tire cover. The handle
may hook on the front edge of the trunk’s
weatherstrip to hold the cover out of the way.
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4. Turn the wing nut counterclockwise and remove it.
5. Remove the compact spare tire.6. Turn the nut holding the jack counterclockwise and
remove it. Then remove the jack and wrench.
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The tools you will need to change a tire include the
jack (A), extension and protection guide (B), and
wheel wrench (C).
Removing the Flat Tire and
Installing the Spare Tire
If the vehicle has steel wheel covers with center caps,
the wheel nuts are hidden behind the cap. To remove
the wheel cover, do the following:
1. Pry off the center cap by using the at end of the
wheel wrench at the notch on the cap.
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