tires SATURN SKY 2007 Owner's Manual

CAUTION: (Continued)

Underinated tires pose the same
danger as overloaded tires. The
resulting accident could cause serious
injury. Check all tires frequently to
maintain the recommended pressure.
Tire pressure should be checked when
your vehicle’s tires are cold. See
Inflation - Tire Pressure on page 292.
Overinated tires are more likely to
be cut, punctured, or broken by a
sudden impact — such as when
you hit a pothole. Keep tires at the
recommended pressure.
Worn, old tires can cause accidents.
If the tire’s tread is badly worn, or
if your vehicle’s tires have been
damaged, replace them.Notice:If your vehicle has P245/45R18 size
tires, they are classied as low-prole
tires. Low-prole tires are more susceptible
to damage from road hazards or curb impact
than standard prole tires. Tire and or
wheel assembly damage can occur when
coming into contact with road hazards like,
potholes or sharp edged objects or when
sliding into a curb. Your Saturn Warranty does
not cover this type of damage. Keep tires
set to the correct ination pressure and when
possible avoid contact with curbs, potholes,
and other road hazards.
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Winter Tires
If your vehicle has P245/45R18 size tires,
they are classied as low-prole performance
tires. These tires are designed for very responsive
driving on wet or dry pavement. If you expect to
drive on snow or ice covered roads often, you
may want to get winter tires for your vehicle.
The low-prole performance tires may not offer
the traction you would like or the same level
of performance as winter tires on snow or ice
covered roads.
Winter tires, in general, are designed for
increased traction on snow and ice covered
roads. With winter tires, there may be decreased
dry road traction, increased road noise and
shorter tire tread life. After switching to winter
tires, be alert for changes in vehicle handling
and braking.See your retailer for details regarding winter tire
availability and proper tire selection. Also, see
Buying New Tires on page 296.
If you choose to use winter tires:
Use tires of the same brand and tread type
on all four wheel positions.
Use only radial ply tires of the same size,
load range, and speed rating as the original
equipment tires.
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.
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Tire Sidewall Labeling
Useful information about a tire is molded into its
sidewall. The example below shows a typical
passenger (p-metric) 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.
(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.
(D) Tire Identication Number (TIN):The letters
and numbers following DOT code are 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.
Passenger (P-Metric) Tire Example
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(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 299.
(G) Maximum Cold Ination Load Limit:
Maximum load that can be carried and the
maximum pressure needed to support that load.
Tire Size
The following illustration shows an example of a
typical passenger (p-metric) 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 from A to Z.
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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 296.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 299.
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 225.
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
Your Vehicle on page 225.
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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 Tire and Loading Information label is attached
to the vehicle’s center pillar (B-pillar), below
the driver’s door latch. 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 Your Vehicle on page 225. How you
load your vehicle affects vehicle handling and
ride comfort, never load your vehicle with more
weight than it was designed to carry.
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When to Check
Check your tires once a month or more.
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.
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Tire Inspection and Rotation
Tires should be rotated every 5,000 to 8,000 miles
(8 000 to 13 000 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.
SeeWhen It Is Time for New Tires on page 296
andWheel Replacement on page 300for
more information.
The purpose of regular rotation is to achieve
more uniform wear for all tires on the vehicle.
The rst rotation is the most important. See
Scheduled Maintenance on page 336.When rotating Goodyear Eagle RSA P245/45R18
non-directional tires, always use the correct
rotation pattern shown here.
Non-Directional Tires
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If your vehicle has Goodyear Eagle F1-GS1
P245/45R18 size tires, they are directional
tires and must roll in a certain direction for the
best overall performance. The direction is shown
by an arrow on the tire sidewall. Because
these tires are directional, they should be rotated
as shown here. These tires should only be
moved from front to rear and rear to front on
the same side of the vehicle.After the tires have been rotated, adjust the front
and rear ination pressures as shown on the
Tire and Loading Information label. SeeLoading
Your Vehicle on page 225for an example of
the Tire and Loading Information label and
its location on your vehicle. Make certain that all
wheel nuts are properly tightened. See “Wheel
Nut Torque” underCapacities and Specications
on page 331.
{CAUTION:
Rust or dirt on a wheel, or on the parts to
which it is fastened, can make wheel nuts
become loose after a time. The wheel could
come off and cause a crash. When you
change a wheel, remove any rust or dirt
from places where the wheel attaches to
the vehicle. In an emergency, you can use
a cloth or a paper towel to do this; but be
sure to use a scraper or wire brush later,
if you need to, to get all the rust or dirt off.Directional Tires
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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
Saturn 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,
Saturn 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 will be followed by a MS,
for mud and snow. SeeTire Sidewall Labeling
on page 287for additional information.
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