wheel size BUICK LACROSSE 2010 Owner's Manual

8-30 Driving and Operating
Uplevel Display Shown, BaseModel Similar
The display on the instrument panel
cluster will show which gear the
vehicle is in. The number indicates
the requested gear range when
moving the shift lever forward or
rearward. The transmission will only allow you
to shift into gears appropriate for the
vehicle speed and engine
Revolutions Per Minute (RPM). The
transmission will not automatically
shift to the next lower gear if the
engine RPM is too high, nor to the
next higher gear when the maximum
engine RPM is reached.
While in the DSC 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 second
gear. A higher gear allows you to
gain more traction on slippery
surfaces.
Drive Systems
All-Wheel Drive
With this feature, engine power is
always sent to all four wheels. It is
fully automatic, and adjusts itself as
needed for road conditions.
When using a compact spare tire on
an AWD vehicle, the system
automatically detects the compact
spare and disables AWD. To restore
AWD operation and prevent
excessive wear on system, replace
the compact spare with a full-size
tire as soon as possible. See
Compact Spare Tire
on page 9‑74for more information.

9-2 Vehicle Care
Tire Pressure MonitorOperation . . . . . . . . . . . . . . . . . . 9-55
Tire Inspection . . . . . . . . . . . . . . . 9-59
Tire Rotation . . . . . . . . . . . . . . . . . 9-59
When It Is Time for New Tires . . . . . . . . . . . . . . . . . . . . . . . 9-60
Buying New Tires . . . . . . . . . . . . 9-61
Different Size Tires and Wheels . . . . . . . . . . . . . . . . . . . . . 9-63
Uniform Tire Quality Grading . . . . . . . . . . . . . . . . . . . . 9-64
Wheel Alignment and Tire Balance . . . . . . . . . . . . . . . . . . . . 9-65
Wheel Replacement . . . . . . . . . 9-66
Tire Chains . . . . . . . . . . . . . . . . . . 9-67
If a Tire Goes Flat . . . . . . . . . . . 9-67
Tire Changing . . . . . . . . . . . . . . . 9-69
Compact Spare Tire . . . . . . . . . 9-74
Jump Starting
Jump Starting . . . . . . . . . . . . . . . . 9-75
Towing
Towing the Vehicle . . . . . . . . . . . 9-79
Recreational Vehicle Towing . . . . . . . . . . . . . . . . . . . . . 9-79
Appearance Care
Exterior Care . . . . . . . . . . . . . . . . 9-82
Interior Care . . . . . . . . . . . . . . . . . 9-86
General Information
For service and parts needs, visit
your dealer/retailer. You will receive
genuine GM parts and GM-trained
and supported service people.
Genuine GM parts have one of
these marks:
California Proposition
65 Warning
Most motor vehicles, including this
one, contain and/or emit chemicals
known to the State of California to
cause cancer and birth defects or
other reproductive harm. Engine
exhaust, many parts and systems,
many fluids, and some component
wear by-products contain and/or
emit these chemicals.

Vehicle Care 9-47
If you choose to use 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 your original equipment
tires may not be available for H, V,
W, Y, and ZR speed rated tires.
If you choose winter tires with a
lower speed rating, never exceed
the tire's maximum speed capability.
Tire Sidewall Labeling
Useful information about a tire is
molded into its sidewall. The
examples below show a typical
passenger vehicle tire and a
compact spare tire sidewall.
Passenger (P-Metric) Tire Example
(A) Tire Size:The tire size is a
combination of letters and
numbers used to define a
particular tire's width, height,
aspect ratio, construction type,
and service description. See the
“Tire Size” illustration later in this
section for more detail.
(B) TPC Spec (Tire
Performance Criteria
Specification)
:Original
equipment tires designed to
GM's specific tire performance criteria have a TPC specification
code molded onto the sidewall.
GM's TPC specifications meet or
exceed all federal safety
guidelines.
(C) DOT (Department of
Transportation)
:The
Department of Transportation
(DOT) code indicates that the
tire is in compliance with the
U.S. Department of
Transportation Motor Vehicle
Safety Standards.
(D) Tire Identification Number
(TIN)
:The letters and numbers
following the DOT (Department
of Transportation) code is the
Tire Identification Number (TIN).
The TIN shows the
manufacturer and plant code,
tire size, and date the tire was
manufactured. The TIN is
molded onto both sides of the
tire, although only one side may
have the date of manufacture.

Vehicle Care 9-49
(E) Tire Inflation:The
temporary use tire or compact
spare tire should be inflated to
420 kPa (60 psi). For more
information on tire pressure and
inflation see Tire Pressure
on
page 9‑53
.
(F) Tire Size
:A combination of
letters and numbers define a
tire's width, height, aspect ratio,
construction type, and service
description. The letter T as the
first character in the tire size
means the tire is for temporary
use only.
(G) TPC Spec (Tire
Performance Criteria
Specification)
:Original
equipment tires designed to
GM's specific tire performance
criteria have a TPC specification
code molded onto the sidewall.
GM's TPC specifications meet or
exceed all federal safety
guidelines.
Tire Designations
Tire Size
The following illustration shows
an example of a typical
passenger vehicle tire size.
(A) Passenger (P-Metric) Tire:
The United States version of a
metric tire sizing system. The
letter P as the first character in
the tire size means a passenger
vehicle tire engineered to
standards set by the U.S. Tire
and Rim Association.
(B) Tire Width
:The three-digit
number indicates the tire section
width in millimeters from
sidewall to sidewall. (C) Aspect Ratio
:A two-digit
number that indicates the tire
height-to-width measurements.
For example, if the tire size
aspect ratio is 60, as shown in
item C of the illustration, it would
mean that the tire's sidewall is
60 percent as high as it is wide.
(D) Construction Code
:A
letter code is used to indicate
the type of ply construction in
the tire. The letter R means
radial ply construction; the
letter D means diagonal or bias
ply construction; and the letter B
means belted-bias ply
construction.
(E) Rim Diameter
:Diameter of
the wheel in inches.

9-60 Vehicle Care
Make certain that all wheel nuts
are properly tightened. See
“Wheel Nut Torque”under
Capacities and Specifications
on
page 11‑2
.
{WARNING
Rust or dirt on a wheel, or on the
parts to which it is fastened, can
make wheel nuts become loose
after time. The wheel could come
off and cause an accident. When
changing a wheel, remove any
rust or dirt from places where the
wheel attaches to the vehicle. In
an emergency, use a cloth or a
paper towel to do this; but be sure
to use a scraper or wire brush
later, if needed, to get all the rust
or dirt off. See If a Tire Goes Flat
on page 9‑67.
When It Is Time for New
Tires
Various factors, such as
maintenance, temperatures, driving
speeds, vehicle loading, and road
conditions influence when you need
new tires.
One way to tell when it is time for
new tires is to check the treadwear
indicators, which appear when the
tires have only 1.6 mm (1/16 inch) or
less of tread remaining. The vehicle needs new tires if any
of the following statements are true:
.You can see the indicators at
three or more places around
the tire.
.You can see 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.

9-62 Vehicle Care
GM recommends replacing tires
in sets of four. This is because
uniform tread depth on all tires
will help keep your vehicle
performing most like it did when
the tires were new. Replacing
less than a full set of tires can
affect the braking and handling
performance of your vehicle.
SeeTire Inspection
on page 9‑59
andTire Rotationon page 9‑59
for information on proper tire
rotation.
{WARNING
Mixing tires could cause you
to lose control while driving.
If you mix tires of different
sizes, brands, or types (radial
and bias-belted tires), the
vehicle may not handle
properly, and you could have
a crash. Using tires of different
sizes, brands, or types may
also cause damage to your
vehicle. Be sure to use the
correct size, brand, and type
of tires on all wheels. It is all
right to drive with your
compact spare temporarily, as
it was developed for use on
your vehicle. See Compact
Spare Tire
on page 9‑74.
{WARNING
If you use bias-ply tires on the
vehicle, the wheel rim flanges
could develop cracks after
many miles of driving. A tire
and/or wheel could fail
suddenly, causing a crash.
Use only radial-ply tires with
the wheels on the vehicle.
If you must replace your
vehicle's tires with those that do
not have a TPC Spec number,
make sure they are the same
size, load range, speed rating,
and construction type (radial and
bias-belted tires) as your
vehicle's original tires.

Vehicle Care 9-63
Vehicles that have a tire
pressure monitoring system
could give an inaccurate
low-pressure warning if non-TPC
Spec rated tires are installed on
your vehicle. Non-TPC Spec
rated tires may give a
low-pressure warning that is
higher or lower than the proper
warning level you would get with
TPC Spec rated tires. SeeTire
Pressure Monitor System
on
page 9‑54
.
Your vehicle's original
equipment tires are listed on the
Tire and Loading Information
Label. See Vehicle Load Limits
on page 8‑12, for more
information about the Tire and
Loading Information Label and
its location on your vehicle.
Different Size Tires and
Wheels
If you add wheels or tires that are a
different size than your original
equipment wheels and tires, this
could affect the way your vehicle
performs, including its braking, ride
and handling characteristics,
stability, and resistance to rollover.
Additionally, if your vehicle has
electronic systems such as anti-lock
brakes, rollover airbags, traction
control, and electronic stability
control, the performance of these
systems can be affected.
{WARNING
If you add different sized wheels,
your vehicle may not provide an
acceptable level of performance
and safety if tires not
recommended for those wheels
are selected. You may increase
the chance that you will crash and
suffer serious injury. Only use GM
specific wheel and tire systems
developed for your vehicle, and
have them properly installed by a
GM certified technician.
See Buying New Tires
on
page 9‑61and Accessories and
Modificationson page 9‑3for
additional information.

Vehicle Care 9-67
Used Replacement Wheels
{WARNING
Putting a used wheel on the
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.
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 you to lose
control of the 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 the
vehicle and tire size combination
and road conditions. Follow that
manufacturer's instructions. To
help avoid damage to the vehicle,
drive slowly, readjust or remove
the device if it is contacting the
vehicle, and do not spin the(Continued)
WARNING (Continued)
vehicle's wheels. If you do find
traction devices that will fit, install
them on the front tires.
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 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 out of the
traffic lane.

Vehicle Care 9-73
Notice:Improperly tightened
wheel nuts can lead to brake
pulsation and rotor damage. To
avoid expensive brake repairs,
evenly tighten the wheel nuts in
the proper sequence and to the
proper torque specification. See
Capacities and Specifications
on
page 11‑2for the wheel nut
torque specification.
13. Tighten the wheel nuts firmly in a crisscross sequence, as
shown. 14. Lower the jack all the way and
remove the jack from under the
vehicle.
15. Tighten the wheel nuts firmly with the wheel wrench.
Notice: Wheel covers will not fit
on your vehicle's compact spare.
If you try to put a wheel cover on
the compact spare, the cover or
the spare could be damaged.
Storing a Flat or Spare Tire
and Tools
{WARNING
Storing a jack, a tire, 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 all these in
the proper place. To store the flat or spare tire and
tools:
1. Place the jack and tools in the
rear storage compartment.
2. Place the flat or spare tire in the storage compartment below the
floor covering.
Secure it with the retainer nut.
If the wheel is larger than the
spare, place the floor cover on
the projecting wheel.
The compact spare is for temporary
use only. Replace the compact
spare tire with a full-size tire as
soon as you can.

9-74 Vehicle Care
Compact Spare Tire
{WARNING
Driving with more than one
compact spare tire at a time could
result in loss of braking and
handling. This could lead to a
crash and you or others could be
injured. Use only one compact
spare tire at a time.
If this vehicle has a compact spare
tire it was fully inflated when the
vehicle was new, however, it can
lose air after a time. Check the
inflation pressure regularly. It should
be 420 kPa (60 psi ). After installing the compact spare
on the vehicle, stop as soon as
possible and make sure the spare
tire is correctly inflated. The
compact spare is made to perform
well at speeds up to 105 km/h
(65 mph) for distances up to
5 000 km (3,000 miles), so you can
finish your trip and have the full-size
tire repaired or replaced at your
convenience. Of course, it is best to
replace the spare with a full-size tire
as soon as possible. The spare tire
will last longer and be in good
shape in case it is needed again.
Notice:
When the compact spare
is installed, do not take the
vehicle through an automatic car
wash with guide rails. The
compact spare can get caught on
the rails which can damage the
tire, wheel and other parts of the
vehicle.
Do not use the compact spare on
other vehicles. Do not mix the compact spare tire or
wheel with other wheels or tires.
They will not fit. Keep the spare tire
and its wheel together.
Notice:
Tire chains will not fit the
compact spare. Using them can
damage the vehicle and can
damage the chains too. Do not
use tire chains on the compact
spare.