
Black plate (65,1)Buick LaCrosse Owner Manual - 2012
Vehicle Care 10-65
Different Size Tires and
Wheels
If wheels or tires are installed that
are a different size than the original
equipment wheels and tires, vehicle
performance, including its braking,
ride and handling characteristics,
stability, and resistance to rollover
may be affected. If the vehicle has
electronic systems such as antilock
brakes, rollover airbags, traction
control, and electronic stability
control, the performance of these
systems can also be affected.
{WARNING
If different sized wheels are used,
there may not be an acceptable
level of performance and safety if
tires not recommended for those
wheels are selected. This
increases the chance of a crash
and serious injury. Only use GM
specific wheel and tire systems
developed for the vehicle, and
have them properly installed by a
GM certified technician.
See Buying New Tires on
page 10‑63 andAccessories and
Modifications on page 10‑3 for
additional information.
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
(NHTSA), 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
(UTQG) system does not apply
to deep tread, winter-type snow
tires, space-saver, or temporary

Black plate (67,1)Buick LaCrosse Owner Manual - 2012
Vehicle Care 10-67
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 specified 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 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 inflated and not overloaded. Excessive speed,
underinflation, or excessive
loading, either separately or in
combination, can cause heat
buildup and possible tire failure.
Wheel Alignment and Tire
Balance
The tires and wheels were aligned
and balanced at the factory to
provide the longest tire life and best
overall performance. Adjustments to
wheel alignment and tire balancing
will not be necessary on a regular
basis. However, check the
alignment if there is unusual tire
wear or if the vehicle is pulling to
one side or the other. If the vehicle
vibrates when driving on a smooth
road, the tires and wheels might
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.
Some aluminum wheels can be
repaired. See your dealer if any of
these conditions exist.
Your dealer will know the kind of
wheel that is needed.
Each new wheel should have the
same load-carrying capacity,
diameter, width, offset, and be
mounted the same way as the one it
replaces.

Black plate (68,1)Buick LaCrosse Owner Manual - 2012
10-68 Vehicle Care
Replace wheels, wheel bolts, wheel
nuts, or Tire Pressure Monitor
System (TPMS) sensors with new
GM original equipment parts.
{WARNING
Using the wrong replacement
wheels, wheel bolts, or wheel
nuts can be dangerous. It could
affect the braking and handling of
the vehicle. Tires can lose air,
and cause loss of control, causing
a crash. 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.
See If a Tire Goes Flat on
page 10‑69 for more information.
Used Replacement Wheels
{WARNING
Replacing a wheel with a used
one is dangerous. How it has
been used or how far it has been
driven may be unknown. It could
fail suddenly and cause a crash.
When replacing wheels, use a
new GM original equipment
wheel.
Tire Chains
{WARNING
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 loss of
control and a crash.
Use another type of traction
device only if its manufacturer
recommends it for the vehicle's
tire size combination and road
conditions. Follow that
manufacturer's instructions. To
avoid vehicle damage, drive slow
and readjust or remove the
traction device if it contacts the
vehicle. Do not spin the wheels.
If traction devices are used, install
them on the front tires.

Black plate (69,1)Buick LaCrosse Owner Manual - 2012
Vehicle Care 10-69
If a Tire Goes Flat
It is unusual for a tire to blow out
while driving, especially if the tires
are maintained properly. SeeTires
on page 10‑47. If air goes out of a
tire, it is much more likely to leak
out slowly. But if there is ever a
blowout, here are a few tips about
what to expect and what to do:
If a front tire fails, the flat tire
creates a drag that pulls the vehicle
toward that side. Take your foot off
the accelerator pedal and grip the
steering wheel firmly. Steer to
maintain lane position, and then
gently brake to a stop, well off the
road, if possible. A rear blowout, particularly on a
curve, acts much like a skid and
may require the same correction as
used in a skid. Stop pressing the
accelerator pedal and steer to
straighten the vehicle. It may be
very bumpy and noisy. Gently brake
to a stop, well off the road,
if possible.
{WARNING
Driving on a flat tire will cause
permanent damage to the tire.
Re-inflating a tire after it has been
driven on while severely
underinflated or flat may cause a
blowout and a serious crash.
Never attempt to re-inflate a tire
that has been driven on while
severely underinflated or flat.
Have your dealer or an authorized
tire service center repair or
replace the flat tire as soon as
possible.
{WARNING
Lifting a vehicle and getting
under it to do maintenance or
repairs is dangerous without the
appropriate safety equipment and
training. If a jack is provided with
the vehicle, it is designed only for
changing a flat tire. If it is used for
anything else, you or others could
be badly injured or killed if the
vehicle slips off the jack. If a jack
is provided with the vehicle, only
use it for changing a flat tire.
If a tire goes flat, avoid further tire
and wheel damage by driving slowly
to a level place, well off the road,
if possible. Turn on the hazard
warning flashers. See Hazard
Warning Flashers on page 6‑4.

Black plate (70,1)Buick LaCrosse Owner Manual - 2012
10-70 Vehicle Care
{WARNING
Changing a tire can be
dangerous. The vehicle can slip
off the jack and roll over or fall
causing injury or death. Find a
level place to change the tire. To
help prevent the vehicle from
moving:1. Set the parking brake firmly.
2. Put an automatic transmission in P (Park) or a
manual transmission in
1 (First) or R (Reverse).
3. Turn off the engine and do not restart while the vehicle
is raised.
4. Do not allow passengers to remain in the vehicle.
5. Place wheel blocks on both sides of the tire at the
opposite corner of the tire
being changed. This vehicle may come with a jack
and spare tire or a tire sealant and
compressor kit. To use the jacking
equipment to change a spare tire
safely, follow the instructions below.
Then see
Tire Changing on
page 10‑87. To use the tire sealant
and compressor kit, see Tire
Sealant and Compressor Kit (With
Pressure Relief Button) on
page 10‑71 orTire Sealant and
Compressor Kit (With Pressure
Deflation Button) on page 10‑78. When the vehicle has a flat tire (B),
use the following example as a
guide to assist you in the placement
of wheel blocks (A).
A. Wheel Block
B. Flat Tire
The following information explains
how to repair or change a tire.

Black plate (72,1)Buick LaCrosse Owner Manual - 2012
10-72 Vehicle Care
{WARNING
Storing the tire sealant and
compressor kit or other
equipment in the passenger
compartment of the vehicle could
cause injury. In a sudden stop or
collision, loose equipment could
strike someone. Store the tire
sealant and compressor kit in its
original location.
If this vehicle has a tire sealant and
compressor kit, there may not be a
spare tire and tire changing
equipment, and on some vehicles
there may not be a place to store
a tire. The tire sealant and compressor
can be used to temporarily seal
punctures up to 6 mm (0.25 in) in
the tread area of the tire. It can also
be used to inflate an
underinflated tire.
If the tire has been separated from
the wheel, has damaged sidewalls,
or has a large puncture, the tire is
too severely damaged for the tire
sealant and compressor kit to be
effective. See
Roadside Assistance
Program (U.S. and Canada) on
page 13‑7 orRoadside Assistance
Program (Mexico) on page 13‑10.
Read and follow all of the tire
sealant and compressor kit
instructions. The kit includes:
A. On/Off Button
B. Selector Switch (Sealant/Air or
Air Only)
C. Pressure Relief Button
D. Pressure Gauge
E. Air Only Hose (Black)
F. Sealant/Air Hose (Clear)
G. Power Plug

Black plate (73,1)Buick LaCrosse Owner Manual - 2012
Vehicle Care 10-73
Tire Sealant
Read and follow the safe handling
instructions on the label adhered to
the compressor.
Check the tire sealant expiration
date on the sealant canister. The
sealant canister should be replaced
before its expiration date.
Replacement sealant canisters are
available at your local dealer. See
“Removal and Installation of the
Sealant Canister”later in this
section.
There is only enough sealant to seal
one tire. After usage, the sealant
canister and sealant/air hose
assembly must be replaced. See
“Removal and Installation of the
Sealant Canister” later in this
section.
Using the Tire Sealant and
Compressor Kit to Temporarily
Seal and Inflate a
Punctured Tire
Follow the directions closely for
correct sealant usage.
When using the tire sealant and
compressor kit during cold
temperatures, warm the kit in a
heated environment for five minutes.
This will help to inflate the tire
faster. If a tire goes flat, avoid further tire
and wheel damage by driving slowly
to a level place. Turn on the hazard
warning flashers. See
Hazard
Warning Flashers on page 6‑4.
See If a Tire Goes Flat on
page 10‑69 for other important
safety warnings.
Do not remove any objects that
have penetrated the tire.
1. Remove the tire sealant and compressor kit from its storage
location. See Storing the Tire
Sealant and Compressor Kit on
page 10‑87.
2. Unwrap the sealant/air hose (F) and the power plug (G).
3. Place the kit on the ground. Make sure the tire valve stem is
positioned close to the ground
so the hose will reach it.
4. Remove the valve stem cap from the flat tire by turning it
counterclockwise.

Black plate (75,1)Buick LaCrosse Owner Manual - 2012
Vehicle Care 10-75
Be careful while handling the
tire sealant and compressor kit
as it could be warm after
usage.
12. Unplug the power plug (G) from the accessory power outlet in
the vehicle.
13. Turn the sealant/air hose (F) counterclockwise to remove it
from the tire valve stem.
14. Replace the tire valve stem cap.
15. Return the sealant/air hose (F) and the power plug (G) back in
their original locations.
16. If the flat tire was able to inflateto the recommended inflation
pressure, remove the
maximum speed label from the sealant canister and place it in
a highly visible location. Do not
exceed the speed on this label
until the damaged tire is
repaired or replaced.
17. Return the equipment to its original storage location in the
vehicle.
18. Immediately drive the vehicle 8 km (5 mi) to distribute the
sealant in the tire.
19. Stop at a safe location and check the tire pressure. Refer
to Steps 1–11 under “Using the
Tire Sealant and Compressor
Kit without Sealant to Inflate a
Tire (Not Punctured).”
If the tire pressure has fallen
more than 68 kPa (10 psi)
below the recommended
inflation pressure, stop driving
the vehicle. The tire is too
severely damaged and the tire
sealant cannot seal the tire.
See Roadside Assistance
Program (U.S. and Canada) on page 13‑7
orRoadside
Assistance Program (Mexico)
on page 13‑10.
If the tire pressure has not
dropped more than 68 kPa
(10 psi) from the recommended
inflation pressure, use the
compressor kit to inflate the tire
to the recommended inflation
pressure.
20. Wipe off any sealant from the wheel, tire, and vehicle.
21. Dispose of the used sealant canister and sealant/air
hose (F) assembly at a local
dealer or in accordance with
local state codes and practices.
22. Replace it with a new canister available from your dealer.
23. After temporarily sealing a tire using the tire sealant and
compressor kit, take the
vehicle to an authorized dealer
within 161 km (100 mi) of
driving to have the tire repaired
or replaced.