2009 GMC ACADIA Owner's Manual

(G) Maximum Cold Ination
Load Limit:Maximum load that
can be carried and the maximum
pressure needed to support
that load.
(A) Temporary Use Only
:The
compact spare tire or temporary
use tire has a tread life of
approximately 3,000 miles
(5 000 km) and should not be
driven at speeds over 65 mph
(105 km/h). The compact spare
tire is for emergency use when aregular road tire has lost air and
gone at. If your vehicle has a
compact spare tire, seeCompact
Spare Tire on page 5-81andIf a
Tire Goes Flat on page 5-55.
(B) Tire Ply Material
:The type
of cord and number of plies in the
sidewall and under the tread.
(C) Tire Identication Number
(TIN)
:The letters and numbers
following the DOT (Department
of Transportation) code is the
Tire Identication 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 Ination
Load Limit
:Maximum load
that can be carried and
the maximum pressure needed
to support that load.(E) Tire Ination
:The
temporary use tire or compact
spare tire should be inated
to 60 psi (420 kPa). For
more information on tire
pressure and ination see
Inflation - Tire Pressure on
page 5-41.
(F) Tire Size
:A combination
of letters and numbers dene a
tire’s width, height, aspect ratio,
construction type, and service
description. The letter T as the
rst character in the tire size
means the tire is for temporary
use only.
(G) TPC Spec (Tire
Performance Criteria
Specication)
:Original
equipment tires designed to
GM’s specic tire performance
criteria have a TPC specication
code molded onto the sidewall.
GM’s TPC specications
meet or exceed all federal
safety guidelines. Compact Spare Tire Example
Service and Appearance Care 5-37

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 rst 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.
(F) Service Description
:These
characters represent the load
range and speed rating of the
tire. The load index represents
the load carry capacity a tire is
certied to carry. The load index
can range from 1 to 279. The
speed rating is the maximum
speed a tire is certied to carry
a load. Speed ratings range
fromAtoZ.
Tire Terminology and
Denitions
Air Pressure:The amount
of air inside the tire pressing
outward on each square inch
of the tire. Air pressure is
expressed in pounds per square
inch (psi) or kilopascal (kPa).
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.
5-38 Service and Appearance Care

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 pounds per square
inch (psi) or kilopascals (kPa)
before a tire has built up heat
from driving. SeeInflation - Tire
Pressure on page 5-41.
Curb Weight
:The weight of a
motor vehicle with standard
and optional equipment including
the maximum capacity of fuel,
oil, and coolant, but without
passengers and cargo.
DOT Markings
:A code
molded into the sidewall of a
tire signifying that the tire is in
compliance with the U.S.Department of Transportation
(DOT) motor vehicle safety
standards. The DOT code
includes the Tire Identication
Number (TIN), an alphanumeric
designator which can also
identify the tire manufacturer,
production plant, brand, and
date of production.
GVWR
:Gross Vehicle Weight
Rating. SeeLoading the Vehicle
on page 4-16.
GAWR FRT
:Gross Axle
Weight Rating for the front axle.
SeeLoading the Vehicle on
page 4-16.
GAWR RR
:Gross Axle
Weight Rating for the rear axle.
SeeLoading the Vehicle on
page 4-16.
Intended Outboard Sidewall
:The side of an asymmetrical tire,
that must always face outward
when mounted on a vehicle.
Kilopascal (kPa)
:The metric
unit for air pressure.Light Truck (LT-Metric) Tire
:A tire used on light duty
trucks and some multipurpose
passenger vehicles.
Load Index
:An assigned
number ranging from 1 to 279
that corresponds to the load
carrying capacity of a tire.
Maximum Ination Pressure
:The maximum air pressure
to which a cold tire can
be inated. The maximum air
pressure is molded onto the
sidewall.
Maximum Load Rating
:The load rating for a tire at
the maximum permissible
ination pressure for that tire.
Maximum Loaded Vehicle
Weight
:The sum of curb
weight, accessory weight,
vehicle capacity weight, and
production options weight.
Service and Appearance Care 5-39

Normal Occupant Weight:The
number of occupants a vehicle
is designed to seat multiplied by
150 lbs (68 kg). SeeLoading
the Vehicle on page 4-16.
Occupant Distribution
:Designated seating positions.
Outward Facing Sidewall
:The side of an asymmetrical tire
that has a particular side that
faces outward when mounted on
a vehicle. The side of the tire
that contains a whitewall, bears
white lettering, or bears
manufacturer, brand, and/or
model name molding that
is higher or deeper than the
same moldings on the
other sidewall of the tire.
Passenger (P-Metric) Tire
:A tire used on passenger
cars and some light duty trucks
and multipurpose vehicles.Recommended Ination
Pressure
:Vehicle
manufacturer’s recommended
tire ination pressure as
shown on the tire placard.
SeeInflation - Tire Pressure
on page 5-41andLoading the
Vehicle on page 4-16.
Radial Ply Tire
:A pneumatic
tire in which the ply cords
that extend to the beads are
laid at 90 degrees to the
centerline of the tread.
Rim
:A metal support for a
tire and upon which the
tire beads are seated.
Sidewall
:The portion of a tire
between the tread and the bead.
Speed Rating
:An alphanumeric
code assigned to a tire indicating
the maximum speed at which a
tire can operate.Traction
:The friction between
the tire and the road surface.
The amount of grip provided.
Tread
:The portion of a tire that
comes into contact with the road.
Treadwear Indicators
:Narrow
bands, sometimes called wear
bars, that show across the tread
of a tire when only 1/16 inch
(1.6 mm) of tread remains.
SeeWhen It Is Time for New
Tires on page 5-48.
UTQGS (Uniform Tire Quality
Grading Standards)
:A tire
information system that provides
consumers with ratings for a
tire’s traction, temperature,
and treadwear. Ratings are
determined by tire manufacturers
using government testing
procedures. The ratings are
molded into the sidewall of the
tire. SeeUniform Tire Quality
Grading on page 5-51.
5-40 Service and Appearance Care

Vehicle Capacity Weight:The
number of designated seating
positions multiplied by 150 lbs
(68 kg) plus the rated cargo load.
SeeLoading the Vehicle on
page 4-16.
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 ination pressure.
See “Tire and Loading
Information Label” underLoading
the Vehicle on page 4-16.
Ination - Tire Pressure
Tires need the correct amount
of air pressure to operate
effectively.
Notice:Do not let anyone tell
you that under-ination or
over-ination is all right. It is
not. If your tires do not have
enough air (under-ination),
you can get the following:
Too much exing
Too much heat
Tire overloading
Premature or irregular wear
Poor handling
Reduced fuel economy
If your tires have too much air
(over-ination), you can get
the following:
Unusual wear
Poor handling
Rough ride
Needless damage from road
hazardsA vehicle specic Tire and
Loading Information label is
attached to your vehicle. This
label shows your vehicle’s
original equipment tires and the
correct ination pressures for
your tires when they are cold.
The recommended cold tire
ination 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, seeLoading
the Vehicle on page 4-16. How
you load your vehicle affects
vehicle handling and ride
comfort. Never load your vehicle
with more weight than it was
designed to carry.
Service and Appearance Care 5-41

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. It should be at
60 psi (420 kPa). For additional
information regarding the
compact spare tire, seeCompact
Spare Tire on page 5-81.
How to Check
Use a good quality pocket-type
gage to check tire pressure.
You cannot tell if your tires are
properly inated simply by
looking at them. Radial tires may
look properly inated even when
they are under-inated. Check
the tire’s ination pressure when
the tires are cold. Cold means
your vehicle has been sitting for
at least three hours or driven
no more than 1 mile (1.6 km).Remove the valve cap from the
tire valve stem. Press the tire
gage rmly onto the valve to get
a pressure measurement. If the
cold tire ination pressure
matches the recommended
pressure on the Tire and Loading
Information label, no further
adjustment is necessary. If the
ination pressure is low, add air
until you reach the recommended
amount.
If you overll 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 inated to the
ination pressure recommended by
the vehicle manufacturer on the
vehicle placard or tire ination
pressure label. (If your vehicle has
tires of a different size than the size
indicated on the vehicle placard or
tire ination pressure label, you
should determine the proper tire
ination 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 signicantly under-inated.
5-42 Service and Appearance Care

Accordingly, when the low tire
pressure telltale illuminates, you
should stop and check your tires as
soon as possible, and inate them to
the proper pressure. Driving on a
signicantly under-inated tire
causes the tire to overheat and can
lead to tire failure. Under-ination
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-ination
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 ash 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.
SeeTire Pressure Monitor Operation
on page 5-44for additional
information.Federal Communications
Commission (FCC) and
Industry and Science Canada
The Tire Pressure Monitor
System (TPMS) operates on a
radio frequency and complies
with Part 15 of the FCC Rules.
Operation is subject to the following
two conditions:
1. This device may not cause
harmful interference.
2. This device must accept any
interference received, including
interference that may cause
undesired operation.
The TPMS operates on a radio
frequency and complies with
RSS-210 of Industry and Science
Canada. Operation is subject to
the following two conditions:
1. This device may not cause
interference.
2. This device must accept any
interference received, including
interference that may cause
undesired operation of the device.
Service and Appearance Care 5-43

Changes or modications to
this system by other than an
authorized service facility could void
authorization to use this equipment.
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
condition exists. TPMS sensors
are mounted onto each tire
and wheel assembly, excluding the
spare tire 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 specic 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
inated to the correct ination
pressure. Using the DIC, tire
pressure levels can be viewed by
the driver. For additional information
and details about the DIC operation
and displays seeDIC Operation and
Displays (With DIC Buttons) on
page 3-46orDIC Operation and
Displays (Without DIC Buttons) on
page 3-51andDIC Warnings and
Messages on page 3-56.The low tire pressure warning light
may come on in cool weather
when the vehicle is rst 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 inated
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 ination pressure for
your vehicle’s tires when they
are cold. SeeLoading the Vehicle
on page 4-16, for an example of
the Tire and Loading Information
label and its location on your
vehicle. Also seeInflation - Tire
Pressure on page 5-41.
Your vehicle’s TPMS can warn you
about a low tire pressure condition
but it does not replace normal tire
maintenance. SeeTire Inspection
and Rotation on page 5-47andTires
on page 5-35.
5-44 Service and Appearance Care