2007 SATURN ION load capacity

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. SeeInation - Tire Pressure
on page 337.
Curb Weight:This means the weight of a motor
vehicle with standard and optional equipment
including the maximum capacity of fuel, oil, and
coolant, but without passengers and cargo.
DOT Markings:A code molded into the sidewall
of a tire signifying that the tire is in compliance
with the U.S. Department of Transportation (DOT)
motor vehicle safety standards. The DOT code
includes the Tire Identication Number (TIN),
an alphanumeric designator which can also identify
the tire manufacturer, production plant, brand,
and date of production.
GVWR:Gross Vehicle Weight Rating.
SeeLoading Your Vehicle on page 250.
GAWR FRT:Gross Axle Weight Rating for the
front axle. SeeLoading Your Vehicle on page 250.
GAWR RR:Gross Axle Weight Rating for the
rear axle. SeeLoading Your Vehicle on page 250.
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Intended Outboard Sidewall:The side of an
asymmetrical tire, that must always face outward
when mounted on a vehicle.
Kilopascal (kPa):The metric unit for air pressure.
Light Truck (LT-Metric) Tire:A tire used on
light duty trucks and some multipurpose passenger
vehicles.
Load Index:An assigned number ranging from
1 to 279 that corresponds to the load carrying
capacity of a tire.
Maximum Ination Pressure:The maximum air
pressure to which a cold tire may be inated.
The maximum air pressure is molded onto
the sidewall.
Maximum Load Rating:The load rating for a tire
at the maximum permissible ination pressure
for that tire.
Maximum Loaded Vehicle Weight:The sum of
curb weight, accessory weight, vehicle capacity
weight, and production options weight.
Normal Occupant Weight:The number of
occupants a vehicle is designed to seat multiplied
by 150 lbs (68 kg). SeeLoading Your Vehicle
on page 250.Occupant Distribution:Designated seating
positions.
Outward Facing Sidewall:The side of an
asymmetrical tire that has a particular side that
faces outward when mounted on a vehicle.
The side of the tire that contains a whitewall, bears
white lettering, or bears manufacturer, brand,
and/or model name molding that is higher
or deeper than the same moldings on the other
sidewall of the tire.
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
Ination - Tire Pressure on page 337andLoading
Your Vehicle on page 250.
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.
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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 341.
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 344.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 250.
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 250.
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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). 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, see
Loading Your Vehicle on page 250. How you load
your vehicle affects vehicle handling and ride
comfort. Never load your vehicle with more weight
than it was designed to carry.
When to Check
Check your tires once a month or more. Do not
forget to check the compact spare tire, it should be
at 60 psi (420 kPa). For additional information
regarding the compact spare tire, seeCompact
Spare Tire on page 365.
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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 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.
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 Saturn original equipment parts. This way,
you will be sure to have the right wheel, wheel
bolts and wheel nuts for your vehicle.
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