2003 PONTIAC GRAND PRIX tire type

Skidding
In a skid, a driver can lose control of the vehicle.
Defensive drivers avoid most skids by taking reasonable
care suited to existing conditions, and by not “overdriving”
those conditions. But skids are always possible.
The three types of skids correspond to your vehicle’s
three control systems. In the braking skid, your wheels
aren’t rolling. In the steering or cornering skid, too much
speed or steering in a curve causes tires to slip and lose
cornering force. And
in the acceleration skid, too much
throttle causes the driving wheels to spin.
A cornering skid is best handled by easing your foot
off
the accelerator pedal.
If you do not have the Enhanced Traction System or the
Traction Control System, or
if the system is off, then
an acceleration skid is also best handled by easing your
foot
off the accelerator pedal.
If your vehicle starts to slide, ease your foot off the
accelerator pedal and quickly steer the way you want
the vehicle to go.
If you start steering quickly enough,
your vehicle may straighten out. Always be ready
for a second skid
if it occurs. Of
course, traction is reduced when water, snow,
ice, gravel or other material is on the road. For safety,
you’ll want to slow down and adjust your driving to these
conditions. It is important to slow down on slippery
surfaces because stopping distance will be longer and
vehicle control more limited.
While driving on
a surface with reduced traction,
try your best to avoid sudden steering, acceleration or
braking (including engine braking by shifting to a
lower gear). Any sudden changes could cause the tires
to slide. You may not realize the surface is slippery
until your vehicle is skidding. Learn to recognize warning
clues
- such as enough water, ice or packed snow
on the road to make a “mirrored surface”
- and slow
down when you have any doubt.
If you have the anti-lock braking system, remember:
It helps avoid only the braking skid.
If you do not have
anti-lock, then in a braking skid (where the wheels
are no longer rolling), release enough pressure on the
brakes to get the wheels rolling again. This restores
steering control. Push the brake pedal down steadily
when you have to stop suddenly. As long as the wheels
are rolling, you will have steering control.
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Bad wear
0 Bad handling
Bad fuel economy
If your tires have too much air (overinflation),
you can get the following:
Unusual wear
Bad handling
Rough ride
Needless damage from road hazards
When to Check
Check your tires once a month or more.
Don’t forget your compact spare tire. It should be
at
60 psi (420 kPa).
How to Check
Use a good quality pocket-type gage to check tire
pressure. You can’t tell
if your tires are properly inflated
simply by looking at them. Radial tires may look
properly inflated even when they’re underinflated.
Be sure to put the valve caps back on the valve stems.
They help prevent leaks by keeping out dirt and
moisture.
Tire Inspection and Rotation
Tires should be rotated every 7,500 miles (1 2 500 km).
Any time you notice unusual wear, rotate your tires
as soon as possible and check wheel alignment.
Also
check for damaged tires or wheels. See When It Is Time
for New Tires on page
5-70 and Wheel Replacement
on page 5-73 for more information.
The purpose of regular rotation is to achieve more
uniform wear for all tires on the vehicle. The first rotation
is the most important. See “Part A: Scheduled
Maintenance Services,’’ in Section
6, for scheduled
rotation intervals.
1
When rotating your tires, always use the correct rotation
pattern shown here.
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The tire has a bump, bulge or split.
The tire has a puncture, cut or other damage that
can’t be repaired well because of the size or
location of the damage.
Buying New Tires
To find out what kind and size of tires you need, look at
the Tire-Loading Information label.
The tires installed on your vehicle when it was new had
a Tire Performance Criteria Specification (TPC Spec)
number on each tire’s sidewall. When you get new tires,
get ones with that same TPC Spec number. That way
your vehicle will continue to have tires that are designed
to give proper endurance, handling, speed rating,
traction, ride and other things during normal service
on
your vehicle. If your tires have an all-season tread
design, the TPC number will be followed by an
“MS”
(for mud and snow).
If you ever replace your tires with those not having
a
TPC Spec number, make sure they are the same
size, load range, speed rating and construction type
(bias, bias-belted or radial) as your original tires.
MiXing tires COUld C8USt2 YOU aQ COnarO!
while driving. If you mix tires of different sizes
or types (radial and bias-belted tires), the
vehicle may not handle properly, and you could have a crash. Using tires of different
sizes may
also cause damage to your vehicle.
Be sure to use the same size and type tires on
all wheels.
It’s all right to drive with your
compact spare temporarily,
it was developed
for use on your vehicle. See “Compact Spare
Tire”
in the index.
.. ~OL ,se bias-ply tires on your vehicle, ..le
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 your vehicle.
I
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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, 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
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 specified 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 significantly from the norm
due to variations in driving habits, service practices and
differences in road characteristics and climate.
Traction - AA, A, 9, 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 specified 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.
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Tire Chains
If your vehicle is an SE model with P225/60R16
size tires, don’t use tire chains, there’s 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
CAUTION: (Continued) instructions. To help avoid damage to your
vehicle, drive slowly, readjust or remove the
device if
it’s contacting your vehicle, and don’t
spin your wheels.
If you do find traction devices that will fit,
install them on the front tires.
Notice; If your vehicle is a GT model, a GTP model,
or if you have an
SE model without P225/60R16
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.
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We have quick, easy access to telephone numbers
of the following additional sewices depending on
your needs:
Hotels
Glass replacemenr
Tire repair facilities
Rental vehicle or taxis
Airports or train stations
Police, fire departments or hospitals
In many instances, mechanical failures are covered
under Pontiac’s comprehensive warranty. However,
when other services are utilized, our advisors will explain
any payment obligations you might incur.
For prompt and efficient assistance when calling, please
provide the following information to give the advisor:
0 Location of vehicle
0 Telephone number of your location
Vehicle model, year and color
Mileage of vehicle
Vehicle Identification Number (VIN)
Vehicle license plate number Pontiac reserves
the right to limit services or
reimbursement to an owner or driver when, in Pontiac’s
judgement, the claims become excessive in frequency
or type of occurrence.
While we hope you never have the occasion
to use our
service, it
is added security while traveling for you
and your family. Remember, we’re only a phone call
away. Pontiac Roadside Assistance: 1 -800-ROADSIDE
or 1-800-762-3743, text telephone (TTY) users,
call 1-888-889-2438.
Canadian Roadside Assistance
Vehicles purchased in Canada have an extensive
Roadside Assistance program accessible from anywhere
in Canada or the United States. Please refer to the
Warranty and Owner Assistance Information book.
Courtesy Transportation
Pontiac has always exemplified quality and value in its
offering of motor vehicles. To enhance your ownership
experience, we and our participating dealers are
proud to offer Courtesy Transportation, a customer
support program for new vehicles.
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