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Tires
We don’t make tires. Your new vehicle comes with
high-quality tires made by a leading tire manufacturer.
These tires are warranted by the tire manufacturers, and
their warranties are delivered with every new Geo.
If
your spare tire is a different brand than your road tires,
you will have a tire warranty folder from each of these
manufacturers.
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Inflation - Tire Pressure
The Tire-Loading Information label which is on the
driver’s door shows the correct inflation pressures for
your tires, when they’re cold.
“Cold” means your
vehicle has been sitting for at least three hours or driven
no more than
a mile.
I
’ NOTICE:
Don’t let anyone tell you that underidation or
~ overinflation is all right. It’s not. If your tires don’t
~ have enough air (underinflation) you can get:
Too much flexing
Too much heat
Tire overloading
Bad wear
Bad handling
Bad fuel economy.
If your tires have too much air (overinflation),
you can get:
Unusual wear
0 Bad handling
Rough ride
Needless damage from road hazards. When to Check
Check your
tires once a month or more. Also, check the
tire pressure of
the spare tire.
How to Check
Use a good quality pocket-type gage to check tire
pressure. Simply looking at the tires will
not tell you the
pressure, especially if you have radial tires
-- which
may look properly inflated even
if they’re underinflated.
If your tires have valve caps, be sure to put them back on.
They help prevent leaks by keeping out dirt and moisture.
Tire Inspection and Rotation
Tires should be inspected every 6,000 to 8,000 miles
(10 000 to 13 000 km) for any signs of unusual wear. If
unusual wear is present, rotate your tires as
soon as
possible and check wheel alignment. Also check for
damaged tires or wheels. See “When It’s Time for New
Tires” and “Wheel Replacement” later in this section 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 “Scheduled
Maintenance Services” in
the Index for scheduled
rotation intervals.
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When rotating your tires, always use one of the correct
rotation patterns shown here.
,
c
t
ri . e1
After the tires have Deen rotated, adjust the front and
rear inflation pressures as shown on the Tire-Loading
Information label. Make certain that all wheel nuts are
properly tightened. See “Wheel
Nut Torque” in the
Index.
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When It’s Time for New Tires
One way to tell when it’s
time for new tires is to
check the treadwear
indicators, which will
appear when your tires have
only
1/16 inch (1.6 rnm) or
less of tread remaining.
You need a new tire
if
0 You can see the indicators at three or more places
0 You can see cord or fabric showing through the tire’s
0 The tread or sidewall is cracked, cut or snagged deep
around the tire.
rubber.
enough to show cord
or fabric.
0 The tire has a bump, bulge or split.
0 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 norrnal 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.
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Treadwear
Uniform Tire Quality Grading
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
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 1/2) 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 - A, B, C
The traction grades, from highest to lowest are: A, B,
and C. They 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 basea
on braking (straight-ahead) traction tests and does not
include cornering (turning) traction.
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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 specified 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 inflated and not
overloaded. Excessive speed, underinflation, or
excessive loading, either separately or in combination,
can cause heat buildup and possible tire failure. These
grades are molded
on the sidewalls of passenger
car tires.
While the tires available as standard or optional
equipment on General Motors vehicles may vary with
respect to these grades, all such tires meet General
Motors performance standards and have been approved
for use on General Motors vehicles. All passenger type
(P Metric) tires must conform to Federal safety
requirements
in addition to these grades.
Wheel Alignment and Tire Balance
The wheels on your vehicle were aligned and balanced
carefully at the factory to give you the longest tire life
and best overall performance.
In most cases, you will
not need to have your wheels
aligned again. However, if you notice unusual tire wear
or your vehicle pulling one way or the other, the
alignment may need to be reset.
If you notice your
vehicle vibrating when driving on
a smooth road, your
wheels may need to be rebalanced.
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Used Replacement Wheels Tire Chains
NOTICE:
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 tires of the drive axle (four-wheel
drive vehicles can use chains on both axles).
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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Aluminum Wheels (If So Equipped)
Your aluminum wheels have a protective coating similar
to the painted surface of your vehicle. Don’t
use strong
soaps, chemicals, chrome polish, abrasive cleaners or
abrasive cleaning brushes
on them because you could
damage this coating. After rinsing thoroughly, a wax
may be applied.
I NOTICE:
If you have aluminum wheels, don’t use an
automatic vehicle wash that has hard silicon
carbide cleaning brushes. These brushes can take
the protective coating
off your aluminum wheels.
Tires
To clean your tires, use a stiff brush with a tire cleaner.
When applying a tire dressing always take care
to wipe
off any overspray or splash from painted surfaces.
Petroleum-based products may damage the paint finish.
Sheet Metal Damage
If your vehicle is damaged and requires sheet metal
repair or replacement, make sure the body repair shop
applies anti-corrosion material to the parts repaired or
replaced to restore corrosion protection.
Finish Damage
Any stone chips, fractures or deep scratches in the finish
should be repaired right away. Bare metal will corrode
quickly
and may develop into a major repair expense.
Minor chips and scratches can be repaired with touch-up
materials available from your dealer
or other service
outlets. Larger areas of finish damage can be corrected
in your dealer’s body and paint shop.
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