wheel size BUICK LACROSSE 2015 Owner's Manual

Black plate (32,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
3-32 Seats and Restraints
Your dealer and the service manual
have information about the location
of the airbag sensors, sensing and
diagnostic module, and airbag
wiring.
In addition, the vehicle has a
passenger sensing system for the
front outboard passenger position,
which includes sensors that are part
of the passenger seat. The
passenger sensing system may not
operate properly if the original seat
trim is replaced with non-GM
covers, upholstery, or trim; or with
GM covers, upholstery, or trim
designed for a different vehicle. Any
object, such as an aftermarket seat
heater or a comfort-enhancing pad
or device, installed under or on top
of the seat fabric, could also
interfere with the operation of the
passenger sensing system. This
could either prevent proper
deployment of the passenger
airbag(s) or prevent the passenger
sensing system from properlyturning off the passenger airbag(s).
See
Passenger Sensing System on
page 3-26.
If the vehicle has rollover roof-rail
airbags, see Different Size Tires
and Wheels on page 10-60 for
additional important information.
If you have to modify your vehicle
because you have a disability and
you have questions about whether
the modifications will affect the
vehicle's airbag system, or if you
have questions about whether the
airbag system will be affected if the
vehicle is modified for any other
reason, call Customer Assistance.
See Customer Assistance Offices
on page 13-3.
Airbag System Check
The airbag system does not need
regularly scheduled maintenance or
replacement. Make sure the airbag
readiness light is working. See
Airbag Readiness Light on
page 5-14.
{Caution
If an airbag covering is damaged,
opened, or broken, the airbag
may not work properly. Do not
open or break the airbag
coverings. If there are any
opened or broken airbag
coverings, have the airbag
covering and/or airbag module
replaced. For the location of the
airbags, see Where Are the
Airbags? on page 3-22. See your
dealer for service.
Replacing Airbag System
Parts after a Crash
{Warning
A crash can damage the airbag
systems in the vehicle.
A damaged airbag system may
not work properly and may not
(Continued)

Black plate (30,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
9-30 Driving and Operating
engine rpm is too high, nor to the
next higher gear when the maximum
engine rpm is reached.
While in Manual Mode, the
transmission will automatically
downshift when the vehicle comes
to a stop. This will allow for more
power during take-off.
When accelerating the vehicle from
a stop in snowy and icy conditions,
you may want to shift into
2 (Second) gear. A higher gear
allows the vehicle to gain more
traction on slippery surfaces.Drive Systems
All-Wheel Drive
Vehicles with this feature always
send engine power to all four
wheels. It is fully automatic, and
adjusts itself as needed for road
conditions.
All-Wheel Drive (AWD) system
performance will be automatically
reduced when the compact spare
tire is in use. To restore full AWD
performance, and prevent excessive
wear to the AWD system, replace
the compact spare tire with a
full-size tire as soon as possible.
SeeCompact Spare Tire on
page 10-77.
Brakes
Antilock Brake
System (ABS)
This vehicle has ABS, an advanced
electronic braking system that helps
prevent a braking skid.
When 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. See Antilock
Brake System (ABS) Warning Light
on page 5-20.

Black plate (2,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
10-2 Vehicle Care
Tire Sidewall Labeling . . . . . . 10-44
Tire Designations . . . . . . . . . . . 10-46
Tire Terminology andDefinitions . . . . . . . . . . . . . . . . 10-47
Tire Pressure . . . . . . . . . . . . . . . 10-50
Tire Pressure for High-Speed
Operation . . . . . . . . . . . . . . . . . 10-51
Tire Pressure Monitor System . . . . . . . . . . . . . . . . . . . 10-51
Tire Pressure Monitor Operation . . . . . . . . . . . . . . . . . 10-52
Tire Inspection . . . . . . . . . . . . . . 10-56
Tire Rotation . . . . . . . . . . . . . . . 10-56
When It Is Time for New Tires . . . . . . . . . . . . . . . . . . . . . . 10-57
Buying New Tires . . . . . . . . . . . 10-58
Different Size Tires and Wheels . . . . . . . . . . . . . . . . . . . 10-60
Uniform Tire Quality Grading . . . . . . . . . . . . . . . . . . . 10-60
Wheel Alignment and Tire Balance . . . . . . . . . . . . . . . . . . . 10-62
Wheel Replacement . . . . . . . . 10-62
Tire Chains . . . . . . . . . . . . . . . . . 10-63
If a Tire Goes Flat . . . . . . . . . . 10-63
Tire Sealant and Compressor Kit . . . . . . . . . . . 10-65 Storing the Tire Sealant and
Compressor Kit . . . . . . . . . . . 10-72
Tire Changing . . . . . . . . . . . . . . 10-72
Compact Spare Tire . . . . . . . . 10-77
Jump Starting
Jump Starting (On-board with eAssist Only) . . . . . . . . . 10-78
Jump Starting (with or without eAssist) . . . . . . . . . . . 10-79
Towing the Vehicle
Towing the Vehicle . . . . . . . . . 10-82
Recreational VehicleTowing . . . . . . . . . . . . . . . . . . . . 10-83
Appearance Care
Exterior Care . . . . . . . . . . . . . . . 10-85
Interior Care . . . . . . . . . . . . . . . . 10-89
Floor Mats . . . . . . . . . . . . . . . . . . 10-93
General Information
For service and parts needs, visit
your dealer. You will receive
genuine GM parts and GM-trained
and supported service people.
Genuine GM parts have one of
these marks:

Black plate (43,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
Vehicle Care 10-43
SeeTire Pressure for
High-Speed Operation on
page 10-51 for inflation pressure
adjustment for high-speed
driving.
All-Season Tires
This vehicle may come with
all-season tires. These tires are
designed to provide good overall
performance on most road surfaces
and weather conditions. Original
equipment tires designed to GM's
specific tire performance criteria
have a TPC specification code
molded onto the sidewall. Original
equipment all-season tires can be
identified by the last two characters
of this TPC code, which will
be “MS.”
Consider installing winter tires on
the vehicle if frequent driving on
snow or ice-covered roads is
expected. All-season tires provide
adequate performance for most
winter driving conditions, but they
may not offer the same level of traction or performance as winter
tires on snow or ice-covered roads.
See
Winter Tires on page 10-43.
Winter Tires
This vehicle was not originally
equipped with winter tires. Winter
tires are designed for increased
traction on snow and ice-covered
roads. Consider installing winter
tires on the vehicle if frequent
driving on ice or snow covered
roads is expected. See your dealer
for details regarding winter tire
availability and proper tire selection.
Also, see Buying New Tires on
page 10-58.
With winter tires, there may be
decreased dry road traction,
increased road noise, and shorter
tread life. After changing to winter
tires, be alert for changes in vehicle
handling and braking.
If using winter tires:
.Use tires of the same brand and
tread type on all four wheel
positions.
.Use only radial ply tires of the
same size, load range, and
speed rating as the original
equipment tires.
Winter tires with the same speed
rating as the original equipment tires
may not be available for H, V, W, Y,
and ZR speed rated tires. If winter
tires with a lower speed rating are
chosen, never exceed the tire's
maximum speed capability.
Summer Tires
This vehicle may come with high
performance summer tires. These
tires have a special tread and
compound that are optimized for
maximum dry and wet road
performance. This special tread and
compound will have decreased
performance in cold climates, and
on ice and snow. We recommend
installing winter tires on the vehicle
if frequent driving at temperatures
below approximately 5°C (40°F) or
on ice or snow covered roads is
expected. See Winter Tires on
page 10-43.

Black plate (52,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
10-52 Vehicle Care
the air pressure in your tires and
transmit tire pressure readings to a
receiver located in the vehicle.
Each tire, including the spare (if
provided), should be checked
monthly when cold and inflated to
the inflation pressure recommended
by the vehicle manufacturer on the
vehicle placard or tire inflation
pressure label. (If your vehicle has
tires of a different size than the size
indicated on the vehicle placard or
tire inflation pressure label, you
should determine the proper tire
inflation pressure for those tires.)
As an added safety feature, your
vehicle has been equipped with a
tire pressure monitoring system
(TPMS) that illuminates a low tire
pressure telltale when one or more
of your tires is significantly
under-inflated.
Accordingly, when the low tire
pressure telltale illuminates, you
should stop and check your tires as
soon as possible, and inflate them
to the proper pressure. Driving on asignificantly under-inflated tire
causes the tire to overheat and can
lead to tire failure. Under-inflation
also reduces fuel efficiency and tire
tread life, and may affect the
vehicle's handling and stopping
ability.
Please note that the TPMS is not a
substitute for proper tire
maintenance, and it is the driver's
responsibility to maintain correct tire
pressure, even if under-inflation has
not reached the level to trigger
illumination of the TPMS low tire
pressure telltale.
Your vehicle has also been
equipped with a TPMS malfunction
indicator to indicate when the
system is not operating properly.
The TPMS malfunction indicator is
combined with the low tire pressure
telltale. When the system detects a
malfunction, the telltale will flash for
approximately one minute and then
remain continuously illuminated.
This sequence will continue upon
subsequent vehicle start-ups as
long as the malfunction exists.When the malfunction indicator is
illuminated, the system may not be
able to detect or signal low tire
pressure as intended. TPMS
malfunctions may occur for a variety
of reasons, including the installation
of replacement or alternate tires or
wheels on the vehicle that prevent
the TPMS from functioning properly.
Always check the TPMS malfunction
telltale after replacing one or more
tires or wheels on your vehicle to
ensure that the replacement or
alternate tires and wheels allow the
TPMS to continue to function
properly.
See
Tire Pressure Monitor
Operation on page 10-52.
See Radio Frequency Statement on
page 13-12.
Tire Pressure Monitor
Operation
This vehicle may have a Tire
Pressure Monitor System (TPMS).
The TPMS is designed to warn the
driver when a low tire pressure

Black plate (53,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
Vehicle Care 10-53
condition exists. TPMS sensors are
mounted onto each tire and wheel
assembly, excluding the spare tire
and wheel assembly. The TPMS
sensors monitor the air pressure in
the tires and transmits the tire
pressure readings to a receiver
located in the vehicle.
When a low tire pressure condition
is detected, the TPMS illuminates
the low tire pressure warning light
located on the instrument cluster.
If the warning light comes on, stop
as soon as possible and inflate the
tires to the recommended pressure
shown on the Tire and Loading
Information label. SeeVehicle Load
Limits on page 9-10.
A message to check the pressure in
a specific tire displays in the Driver
Information Center (DIC). The low tire pressure warning light and the
DIC warning message come on at
each ignition cycle until the tires are
inflated to the correct inflation
pressure. Using the DIC, tire
pressure levels can be viewed. For
additional information and details
about the DIC operation and
displays see
Driver Information
Center (DIC) on page 5-28.
The low tire pressure warning light
may come on in cool weather when
the vehicle is first started, and then
turn off as the vehicle is driven. This
could be an early indicator that the
air pressure is getting low and
needs to be inflated to the proper
pressure.
A Tire and Loading Information
label, attached to your vehicle,
shows the size of the original
equipment tires and the correct
inflation pressure for the tires when
they are cold. See Vehicle Load
Limits on page 9-10, for an example
of the Tire and Loading Information
label and its location. Also see Tire
Pressure on page 10-50. The TPMS can warn about a low
tire pressure condition but it does
not replace normal tire
maintenance. See
Tire Inspection
on page 10-56, Tire Rotation on
page 10-56 andTires on
page 10-42.
{Caution
Tire sealant materials are not all
the same. A non-approved tire
sealant could damage the TPMS
sensors. TPMS sensor damage
caused by using an incorrect tire
sealant is not covered by the
vehicle warranty. Always use only
the GM approved tire sealant
available through your dealer or
included in the vehicle.
TPMS Malfunction Light and
Message
The TPMS will not function properly
if one or more of the TPMS sensors
are missing or inoperable. When the
system detects a malfunction, the

Black plate (56,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
10-56 Vehicle Care
Tire Inspection
We recommend that the tires,
including the spare tire, if the
vehicle has one, be inspected
for signs of wear or damage at
least once a month.
Replace the tire if:
.The indicators at three or
more places around the tire
can be seen.
.There is cord or fabric
showing through the tire's
rubber.
.The tread or sidewall is
cracked, cut, or snagged
deep enough to show cord or
fabric.
.The tire has a bump, bulge,
or split.
.The tire has a puncture, cut,
or other damage that cannot
be repaired well because of
the size or location of the
damage.
Tire Rotation
Tires should be rotated every
12 000 km (7,500 mi). See
Maintenance Schedule on
page 11-2.
Tires are rotated to achieve a
uniform wear for all tires. The
first rotation is the most
important.Anytime unusual wear is
noticed, rotate the tires as soon
as possible, check for proper tire
inflation pressure, and check for
damaged tires or wheels. If the
unusual wear continues after the
rotation, check the wheel
alignment. See
When It Is Time
for New Tires on page 10-57
and Wheel Replacement on
page 10-62.
Use this rotation pattern when
rotating the tires.

Black plate (59,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
Vehicle Care 10-59
If proper rotation and
maintenance have been done,
all four tires should wear out at
about the same time. SeeTire
Rotation on page 10-56.
However, if it is necessary to
replace only one axle set of
worn tires, place the new tires
on the rear axle.
Winter tires with the same speed
rating as the original equipment
tires may not be available for H,
V, W, Y and ZR speed rated
tires. Never exceed the winter
tires’ maximum speed capability
when using winter tires with a
lower speed rating.
{Warning
Tires could explode during
improper service. Attempting
to mount or dismount a tire
could cause injury or death.
(Continued)
Warning (Continued)
Only your dealer or authorized
tire service center should
mount or dismount the tires.
{Warning
Mixing tires of different sizes,
brands, or types may cause
loss of control of the vehicle,
resulting in a crash or other
vehicle damage. Use the
correct size, brand, and type
of tires on all wheels.
{Warning
Using bias-ply tires on the
vehicle may cause the wheel
rim flanges to develop cracks
after many miles of driving.
(Continued)
Warning (Continued)
A tire and/or wheel could fail
suddenly and cause a crash.
Use only radial-ply tires with
the wheels on the vehicle.
If the vehicle tires must be
replaced with a tire that does not
have a TPC Spec number, make
sure they are the same size,
load range, speed rating, and
construction (radial) as the
original tires.
Vehicles that have a tire
pressure monitoring system
could give an inaccurate
low-pressure warning if non-TPC
Spec rated tires are installed.
See Tire Pressure Monitor
System on page 10-51.

Black plate (60,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
10-60 Vehicle Care
The Tire and Loading
Information label indicates the
original equipment tires on the
vehicle. SeeVehicle Load Limits
on page 9-10.
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, electronic stability control,
or All-Wheel Drive, 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 10-58 andAccessories and
Modifications on page 10-3.
Uniform Tire Quality
Grading
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 tires,
compact 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.

Black plate (63,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
Vehicle Care 10-63
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(Continued)
Warning (Continued)
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.
If a Tire Goes Flat
It is unusual for a tire to blow out
while driving, especially if the tires
are maintained properly. See Tires
on page 10-42. 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.