tire size CHEVROLET COBALT 2008 1.G Owners Manual

The Tire and Loading Information label also shows
the tire size of the original equipment tires (C) and
the recommended cold tire ination pressures (D).
For more information on tires and ination seeTires
on page 5-49andInflation - Tire Pressure on
page 5-56.
There is also important loading information on the
Certication label. It tells you the Gross Vehicle
Weight Rating (GVWR) and the Gross Axle Weight
Rating (GAWR) for the front and rear axle; see
“Certication Label” later in this section.
Steps for Determining Correct Load Limit
1.Locate the statement “The combined weight
of occupants and cargo should never exceed
XXX kg or XXX lbs” on your vehicle placard.
2.Determine the combined weight of the driver
and passengers that will be riding in your
vehicle.
3.Subtract the combined weight of the driver
and passengers from XXX kg or XXX lbs.
4.The resulting gure equals the available
amount of cargo and luggage load capacity.
For example, if the “XXX” amount equals
1400 lbs and there will be ve 150 lb
passengers in your vehicle, the amount of
available cargo and luggage load capacity is
650 lbs (1400−750 (5 x 150) = 650 lbs).
5.Determine the combined weight of luggage
and cargo being loaded on the vehicle. That
weight may not safely exceed the available
cargo and luggage load capacity calculated
in Step 4.
6.If your vehicle will be towing a trailer, the load
from your trailer will be transferred to your
vehicle. Consult this manual to determine how
this reduces the available cargo and luggage
load capacity of your vehicle.
If your vehicle can tow a trailer, seeTowing a
Trailer (Manual Transmission) on page 4-34
orTowing a Trailer (Automatic Transmission)
on page 4-34for important information on
towing a trailer, towing safety rules, and
trailering tips.
4-28

Tire Pressure Monitor Operation.....................5-59
Tire Inspection and Rotation...........................5-63
When It Is Time for New Tires.......................5-65
Buying New Tires.........................................5-66
Different Size Tires and Wheels......................5-68
Uniform Tire Quality Grading..........................5-68
Wheel Alignment and Tire Balance..................5-70
Wheel Replacement......................................5-70
Tire Chains..................................................5-72
If a Tire Goes Flat........................................5-73
Changing a Flat Tire.....................................5-74
Removing the Spare Tire and Tools................5-75
Removing the Flat Tire and Installing the
Spare Tire (Sport Model).............................5-80
Removing the Flat Tire and Installing the
Spare Tire (All Models Except Sport)...........5-89
Storing a Flat or Spare Tire and Tools............5-93
Compact Spare Tire......................................5-94
Appearance Care............................................5-95
Interior Cleaning...........................................5-95
Fabric/Carpet...............................................5-96
Leather.......................................................5-97
Instrument Panel, Vinyl, and Other
Plastic Surfaces........................................5-98
Care of Safety Belts......................................5-98
Weatherstrips...............................................5-98Washing Your Vehicle...................................5-99
Cleaning Exterior Lamps/Lenses.....................5-99
Finish Care..................................................5-99
Windshield and Wiper Blades.......................5-100
Aluminum or Chrome-Plated Wheels
and Trim................................................5-101
Tires.........................................................5-101
Sheet Metal Damage...................................5-102
Finish Damage...........................................5-102
Underbody Maintenance...............................5-102
Chemical Paint Spotting...............................5-102
Vehicle Care/Appearance Materials................5-103
Vehicle Identication.....................................5-104
Vehicle Identication Number (VIN)................5-104
Service Parts Identication Label...................5-104
Electrical System..........................................5-105
Add-On Electrical Equipment.........................5-105
Headlamp Wiring........................................5-105
Windshield Wiper Fuses...............................5-105
Power Windows and Other Power Options......5-105
Fuses and Circuit Breakers..........................5-106
Floor Console Fuse Block............................5-106
Engine Compartment Fuse Block...................5-108
Capacities and Specications........................5-112
Section 5 Service and Appearance Care
5-2

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.(A) Tire Size:The tire size is a combination of
letters and numbers used to dene 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
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. If your vehicle has
205/55R16 size tires, they meet the GM TPC Spec
rating, but the TPC Spec code has not been
molded onto the tire’s sidewall.
(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.
Passenger (P-Metric) Tire Example
5-50

(D) Tire Identication Number (TIN):The letters
and numbers following 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.
(E) Tire Ply Material
:The type of cord and
number of plies in the sidewall and under
the tread.
(F) Uniform Tire Quality Grading (UTQG)
:Tire manufacturers are required to grade tires
based on three performance factors: treadwear,
traction and temperature resistance. For more
information seeUniform Tire Quality Grading
on page 5-68.
(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 a regular road tire has lost air and gone at.
If your vehicle has a compact spare tire, see
Compact Spare Tire on page 5-94andIf a Tire
Goes Flat on page 5-73. Compact Spare Tire Example
5-51

(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 seeInflation - Tire Pressure
on page 5-56.
(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.
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. A tire size
without the letter P as the rst character is certied
to European standards.
5-52

(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 from A to Z.
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.
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 5-56.
5-53

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. See
Inflation - Tire Pressure on page 5-56and
Loading Your Vehicle on page 4-27.
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 5-65.
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. See
Uniform Tire Quality Grading on page 5-68.
Vehicle Capacity Weight
:The number of
designated seating positions multiplied by
150 lbs (68 kg) plus the rated cargo load.
SeeLoading Your Vehicle on page 4-27.
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” under
Loading Your Vehicle on page 4-27.
5-55

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.
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.
5-57

Tire Pressure Monitor Operation
The Tire Pressure Monitor System (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. 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 turns on 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 thecorrect 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 on page 3-40
andDIC Warnings and Messages on page 3-43.
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 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 Your Vehicle on page 4-27, for an
example of the Tire and Loading Information label and
its location on your vehicle. Also seeInflation - Tire
Pressure on page 5-56.
Your vehicle’s TPMS system can warn you about a low
tire pressure condition but it does not replace normal
tire maintenance. SeeTire Inspection and Rotation
on page 5-63andTires on page 5-49.
Notice:Liquid tire sealants could damage the
Tire Pressure Monitor System (TPMS) sensors.
Sensor damage caused by using a tire sealant
is not covered by your warranty. Do not use
liquid tire sealants.
5-59

When It Is Time for New Tires
Various factors, such as maintenance, temperatures,
driving speeds, vehicle loading, and road conditions
inuence when you need new tires.
One way to tell when it is
time for new tires is to
check the treadwear
indicators, which will
appear when your tires
have only 1/16 inch
(1.6 mm) or less of
tread remaining.
You need 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.
The rubber in tires degrades over time, even if they
are not being used. This is also true for the spare tire,
if your vehicle has one. Multiple conditions affect
how fast this aging takes place, including temperatures,
loading conditions, and ination pressure maintenance.
With proper care and maintenance tires will typically
wear out before they degrade due to age. If you
are unsure about the need to replace your tires as
they get older, consult the tire manufacturer for more
information.
5-65