CHEVROLET COBALT 2007 1.G Owners Manual

When It Is Time for 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 a new tire 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.
Buying New Tires
GM has developed and matched specic 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
Specication (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 specications 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 by the tire manufacturer.
If the tires have an all-season tread design,
the TPC spec number is followed by an MS
for mud and snow. SeeTire Sidewall Labeling
on page 340for additional information.
351

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.
{CAUTION:
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.
SeeCompact Spare Tire on page 372.
{CAUTION:
If you use bias-ply tires on your vehicle,
the wheel rim anges 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 your 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.
Your vehicle’s original equipment tires are listed
on the Tire and Loading Information label.
This label is attached to the vehicle’s center pillar
(B-pillar). SeeLoading Your Vehicle on page 259,
for more information about the Tire and Loading
Information Label and its location on your vehicle.
352

Different Size Tires and Wheels
If you add wheels or tires that are a different size
than your original equipment wheels and tires, this
may 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, traction control, and electronic
stability control, the performance of these systems
can be affected.{CAUTION:
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 specic wheel and
tire systems developed for your vehicle,
and have them properly installed by a
GM certied technician.
SeeBuying New Tires on page 351and
Accessories and Modications on page 280for
additional information.
353

Uniform Tire Quality Grading
Quality grades can be found where applicable on
the tire sidewall between tread shoulder and
maximum section width. For example:
Treadwear 200 Traction AA Temperature A
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-type
snow tires, space-saver, or temporary use 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.
Treadwear
The treadwear grade is a comparative rating based
on the wear rate of the tire when tested under
controlled conditions on a specied government
test course. For example, a tire graded 150 would
wear one and a half (1.5) times as well on the
government course as a tire graded 100. The
relative performance of tires depends upon the
actual conditions of their use, however, and may
depart signicantly from the norm due to variations
in driving habits, service practices, and differences
in road characteristics and climate.
Traction – AA, A, B, C
The traction grades, from highest to lowest,
are AA, A, B, and C. Those grades represent
the tire’s ability to stop on wet pavement as
measured under controlled conditions on specied
government test surfaces of asphalt and concrete.
A tire marked C may have poor traction
performance.
Warning:The traction grade assigned to this
tire is based on straight-ahead braking traction
tests, and does not include acceleration, cornering,
hydroplaning, or peak traction characteristics.
354

Temperature – A, B, C
The temperature grades are A (the highest), B,
and C, representing the tire’s resistance to the
generation of heat and its ability to dissipate heat
when tested under controlled conditions on a
specied indoor laboratory test wheel. Sustained
high temperature can cause the material of the tire
to degenerate and reduce tire life, and excessive
temperature can lead to sudden tire failure.
The grade C corresponds to a level of performance
which all passenger car tires must meet under the
Federal Motor Vehicle Safety Standard No. 109.
Grades B and A represent higher levels of
performance on the laboratory test wheel than
the minimum required by law.
Warning:The temperature grade for this tire is
established for a tire that is properly inated and
not overloaded. Excessive speed, underination,
or excessive loading, either separately or in
combination, can cause heat buildup and
possible tire failure.
Wheel Alignment and Tire Balance
The tires and wheels on your vehicle were aligned
and balanced carefully at the factory to give you
the longest tire life and best overall performance.
Adjustments to wheel alignment and tire balancing
will not be necessary on a regular basis. However,
if you notice unusual tire wear or your vehicle
pulling to one side or the other, the alignment may
need to be checked. If you notice your vehicle
vibrating when driving on a smooth road, your tires
and wheels may need to be rebalanced. See your
dealer/retailer for proper diagnosis.
Wheel Replacement
Replace any wheel that is bent, cracked, or badly
rusted or corroded. If wheel nuts keep coming
loose, the wheel, wheel bolts, and wheel nuts
should be replaced. If the wheel leaks air, replace
it (except some aluminum wheels, which can
sometimes be repaired). See your dealer/retailer
if any of these conditions exist.
Your dealer/retailer will know the kind of wheel
you need.
355

Each new wheel should have the same
load-carrying capacity, diameter, width, offset
and be mounted the same way as the one
it replaces.
If you need to replace any of your wheels,
wheel bolts, or wheel nuts, replace them only
with new GM original equipment parts. This way,
you will be sure to have the right wheel, wheel
bolts, and wheel nuts for your vehicle.
{CAUTION:
Using the wrong replacement wheels,
wheel bolts, or wheel nuts on your vehicle
can be dangerous. It could affect the
braking and handling of your vehicle,
make your tires lose air and make you
lose control. You could have a collision
in which you or others could be injured.
Always use the correct wheel, wheel bolts,
and wheel nuts for replacement.Notice:The wrong wheel can also cause
problems with bearing life, brake cooling,
speedometer or odometer calibration, headlamp
aim, bumper height, vehicle ground clearance,
and tire or tire chain clearance to the body and
chassis.
SeeChanging a Flat Tire on page 358for more
information.
Used Replacement Wheels
{CAUTION:
Putting a used wheel on your 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.
356

Tire Chains
{CAUTION:
If your vehicle has P205/55R16, P205/
50R17 or 215/45R18 size tires, do not use
tire chains. They can damage your vehicle
because 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
your 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 your vehicle and tire size
combination, and road conditions.
Follow that manufacturer’s instructions.
CAUTION: (Continued)
CAUTION: (Continued)
To help avoid damage to your vehicle,
drive slowly, readjust, or remove the
device if it is contacting your vehicle,
and do not spin your vehicle’s wheels.
If you do nd traction devices that will t,
install them on the front tires.
Notice:If your vehicle has a tire size other
than P205/55R16, P205/50R17 or 215/45R18 size
tires, use tire chains only where legal and only
when you must. Use only SAE Class S-type
chains that are the proper size for your tires.
Install them on the front tires and tighten them
as tightly as possible with the ends securely
fastened. Drive slowly and follow the chain
manufacturer’s instructions. If you can hear
the chains contacting your vehicle, stop and
retighten them. If the contact continues, slow
down until it stops. Driving too fast or spinning
the wheels with chains on will damage your
vehicle.
357

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 at tire will create a drag
that pulls the vehicle toward that side. Take
your foot off the accelerator pedal and grip the
steering wheel rmly. Steer to maintain lane
position, and then gently brake to a stop well
out of the traffic lane.
A rear blowout, particularly on a curve, acts much
like a skid and may require the same correction you
would use in a skid. In any rear blowout remove
your foot from the accelerator pedal. Get the vehicle
under control by steering the way you want the
vehicle to go. It may be very bumpy and noisy,
but you can still steer. Gently brake to a stop,
well off the road if possible.{CAUTION:
Lifting a vehicle and getting under it to
do maintenance or repairs is dangerous
without the appropriate safety equipment
and training. The jack provided with your
vehicle is designed only for changing a
at tire. If it is used for anything else, you
or others could be badly injured or killed
if the vehicle slips off the jack. Use the
jack provided with your vehicle only for
changing a at tire.
If a tire goes at, the next part shows how to
use the jacking equipment to change a at
tire safely.
Changing a Flat Tire
If a tire goes at, avoid further tire and wheel
damage by driving slowly to a level place.
Turn on your hazard warning ashers.
358

{CAUTION:
Changing a tire can be dangerous. The
vehicle can slip off the jack and roll over
or fall on you or other people. You and
they could be badly injured or even killed.
Find a level place to change your tire.
To help prevent the vehicle from moving:
1. Set the parking brake rmly.
2. Put an automatic transaxle shift lever
in PARK (P), or shift a manual
transaxle to FIRST (1) or REVERSE (R).
3. Turn off the engine and do not restart
while the vehicle is raised.
4. Do not allow passengers to remain in
the vehicle.
To be even more certain the vehicle will not
move, you should put blocks at the front
and rear of the tire farthest away from the
one being changed. That would be the tire
on the other side, at the opposite end of
the vehicle.When you have a at tire, use the following
example as a guide to assist you in the placement
of wheel blocks.
The following information will tell you how to use
the jack and change a tire.
359

Removing the Spare Tire and Tools
The equipment you will need is located in
the trunk.
Base Models
1. Open the trunk. SeeTrunk on page 102for
more information.
2. Lift the trunk liner to access the spare tire
and tools.
360