2010 GMC ACADIA tire size

Vehicle Care 10-39
compact spare tire, see
Compact Spare Tire
on
page 10‑77
and If a Tire Goes
Flat
on page 10‑56.
(C) 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.
(D) Maximum Cold Inflation
Load Limit
:Maximum load that
can be carried and the
maximum pressure needed to
support that load. (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 10‑43
.
(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.

10-40 Vehicle Care
(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.
(F) Service Description
:These
characters represent the load
index and speed rating of the
tire. The load index represents
the load carry capacity a tire is certified to carry. The speed
rating is the maximum speed a
tire is certified to carry a load.
Tire Terminology and
Definitions
Air Pressure:The amount of
air inside the tire pressing
outward on each square inch of
the tire. Air pressure is
expressed in psi (pounds per
square inch) or kPa (kilopascal).
Accessory Weight
:This
means the combined weight of
optional accessories. Some
examples of optional
accessories are, automatic
transmission, power steering,
power brakes, power windows,
power seats, and air
conditioning.
Aspect Ratio
:The relationship
of a tire's height to its width. Belt
:A rubber coated layer of
cords that is located between
the plies and the tread. Cords
may be made from steel or other
reinforcing materials.
Bead
:The tire bead contains
steel wires wrapped by steel
cords that hold the tire onto
the rim.
Bias Ply Tire
:A pneumatic tire
in which the plies are laid at
alternate angles less than
90 degrees to the centerline of
the tread.
Cold Tire Pressure
:The
amount of air pressure in a tire,
measured in psi (pounds per
square inch) or kPa (kilopascal)
before a tire has built up heat
from driving. See Tire Pressure
on page 10‑43.

Vehicle Care 10-43
Vehicle Maximum Load on the
Tire
:Load on an individual tire
due to curb weight, accessory
weight, occupant weight, and
cargo weight.
Vehicle Placard
:A label
permanently attached to a
vehicle showing the vehicle's
capacity weight and the original
equipment tire size and
recommended inflation pressure.
See “Tire and Loading
Information Label” underVehicle
Load Limits
on page 9‑10.
Tire Pressure
Tires need the correct amount of
air pressure to operate
effectively.
Notice:Do not let anyone tell
you that under-inflation or
over-inflation is all right. It is not. If your tires do not have
enough air (under-inflation),
you can get the following:
.Too much flexing
.Too much heat
.Tire overloading
.Premature or
irregular wear
.Poor handling
.Reduced fuel economy
If your tires have too much air
(over-inflation), you can get
the following:
.Unusual wear
.Poor handling
.Rough ride
.Needless damage from
road hazards A vehicle specific Tire and
Loading Information label is
attached to your vehicle. This
label shows your vehicle's
original equipment tires and the
correct inflation pressures for
your tires when they are cold.
The recommended cold tire
inflation pressure, shown on the
label, is the minimum amount of
air pressure needed to support
your vehicle's maximum load
carrying capacity.
For additional information
regarding how much weight your
vehicle can carry, and an
example of the Tire and Loading
Information label, see
Vehicle
Load Limits
on page 9‑10. How
you load your vehicle affects
vehicle handling and ride
comfort. Never load your vehicle
with more weight than it was
designed to carry.

10-44 Vehicle Care
When to Check
Check your tires once a month
or more. Do not forget to check
the compact spare tire, if the
vehicle has one. The compact
spare should be at 60 psi
(420 kPa). For additional
information regarding the
compact spare tire, see
Compact Spare Tire
on
page 10‑77
.
How to Check
Use a good quality pocket-type
gage to check tire pressure. You
cannot tell if your tires are
properly inflated simply by
looking at them. Radial tires may
look properly inflated even when
they are under-inflated. Check
the tire's inflation pressure when
the tires are cold. Cold means
your vehicle has been sitting for
at least three hours or driven no
more than 1.6 km (1 mile). Remove the valve cap from the
tire valve stem. Press the tire
gage firmly onto the valve to get
a pressure measurement. If the
cold tire inflation pressure
matches the recommended
pressure on the Tire and
Loading Information label, no
further adjustment is necessary.
If the inflation pressure is low,
add air until you reach the
recommended amount.
If you overfill the tire, release air
by pushing on the metal stem in
the center of the tire valve.
Re-check the tire pressure with
the tire gage.
Be sure to put the valve caps
back on the valve stems. They
help prevent leaks by keeping
out dirt and moisture.
Tire Pressure Monitor
System
The Tire Pressure Monitor System
(TPMS) uses radio and sensor
technology to check tire pressure
levels. The TPMS sensors monitor
the air pressure in your vehicle's
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.)

10-46 Vehicle Care
and wheel assembly, if the vehicle
has one. The TPMS sensors
monitor the air pressure in the
vehicle's 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 panel
cluster.
At the same time a message to
check the pressure in a specific tire
appears on the Driver Information
Center (DIC) display. 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 bythe driver. For additional information
and details about the DIC operation
and displays see
Driver Information
Center (DIC) (With DIC Buttons)
on
page 5‑23or Driver Information
Center (DIC) (Without DIC Buttons)
on page 5‑28and Tire Messageson page 5‑41.
The low tire pressure warning light
may come on in cool weather when
the vehicle is first started, and then
turn off as you start to drive. This
could be an early indicator that the
air pressure in the tire(s) are getting
low and need to be inflated to the
proper pressure.
A Tire and Loading Information
label, attached to your vehicle,
shows the size of your vehicle's
original equipment tires and the
correct inflation pressure for your
vehicle's 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 on your vehicle.
Also see Tire Pressure
on
page 10‑43. Your vehicle's TPMS can warn you
about a low tire pressure condition
but it does not replace normal tire
maintenance. See
Tire Inspection
on page 10‑49,Tire Rotationon
page 10‑49and Tires on
page 10‑37.
Notice: Using non-approved tire
sealants could damage the Tire
Pressure Monitor System (TPMS)
sensors. TPMS sensor damage
caused by using an incorrect tire
sealant is not covered by the
vehicle warranty. Always use the
GM approved tire sealant
available through your dealer/
retailer.
Factory-installed Tire Inflator Kits
use a GM approved liquid tire
sealant. Using non-approved tire
sealants could damage the TPMS
sensors. See Tire Sealant and
Compressor Kit
on page 10‑58for
information regarding the inflator kit
materials and instructions.

10-50 Vehicle Care
Make certain that all wheel nuts
are properly tightened. See
“Wheel Nut Torque”under
Capacities and Specifications
on
page 12‑2
.
{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 10‑56.
Make sure the spare tire, if the
vehicle has one, is stored
securely. Push, pull, and then try to rotate or turn the tire. If it
moves, tighten the cable. See
Tire Changing
on page 10‑66.
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.

Vehicle Care 10-51
The rubber in tires degrades over
time. This is also true for the spare
tire, if the vehicle has one, even if it
is not being used. Multiple
conditions affect how fast this aging
takes place, including temperatures,
loading conditions, and inflation
pressure maintenance. With proper
care and maintenance tires typically
wear out before they degrade due to
age. If you are unsure about the
need to replace the tires as they get
older, consult the tire manufacturer
for more information.Buying New Tires
GM has developed and matched
specific tires for your vehicle.
The original equipment tires
installed on your vehicle, when it
was new, were designed to meet
General Motors Tire
Performance Criteria
Specification (TPC Spec)
system rating. If you need
replacement tires, GM strongly
recommends that you get tires
with the same TPC Spec rating.
This way, your vehicle will
continue to have tires that are
designed to give the same
performance and vehicle safety,
during normal use, as the
original tires.GM's exclusive TPC Spec
system considers over a dozen
critical specifications that impact
the overall performance of your
vehicle, including brake system
performance, ride and handling,
traction control, and tire
pressure monitoring
performance. GM's TPC Spec
number is molded onto the tire's
sidewall near the tire size. If the
tires have an all-season tread
design, the TPC Spec number
will be followed by an MS for
mud and snow. See
Tire
Sidewall Labeling
on page 10‑37
for additional information.

10-52 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 10‑49
andTire Rotationon page 10‑49
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
(Continued)
WARNING (Continued)
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 10‑77.
{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.
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. See
Tire
Pressure Monitor System
on
page 10‑44
.
Your vehicle's original
equipment tires are listed on the
Tire and Loading Information
Label. See Vehicle Load Limits