tire pressure SATURN ION 2007 User Guide

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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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.
High-Speed Operation
{CAUTION:
Driving at high speeds, 100 mph (160 km/h)
or higher, puts an additional strain on tires.
Sustained high-speed driving causes
excessive heat build up and can cause
sudden tire failure. You could have a crash
and you or others could be killed. Some
high-speed rated tires require ination
pressure adjustment for high speed
operation. When speed limits and road
conditions are such that a vehicle can be
driven at high speeds, make sure the tires
are rated for high speed operation, in
excellent condition, and set to the correct
cold tire ination pressure for the
vehicle load.
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The low-prole performance tires, size
215/45ZR17, require tire ination pressure
adjustment when driving your vehicle at speeds of
100 mph (160 km/h) or higher. Set the cold tire
ination pressure to 33 psi (227 kPa) for the front
and rear tires when operating your vehicle at
high-speed conditions.
When you end high-speed driving, return the tires
to the cold ination pressure shown on the Tire
and Loading Information Label. SeeLoading Your
Vehicle on page 250andInation - Tire Pressure
on page 337.
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 341
andWheel Replacement on page 346for
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. SeeScheduled
Maintenance on page 391.
When rotating non-directional tires, always use the
correct rotation pattern shown here.Non-Directional Tires
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If your vehicle has 215/45ZR17 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.
Do not include the compact spare tire in your tire
rotation.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 250for 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 384.
{CAUTION:
Rust or dirt on a wheel, or on the parts to
which it is fastened, can make wheel bolts
become loose after a time. The wheel
could come off and cause an accident.
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. SeeChanging a Flat Tire
on page 350.Directional Tires
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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 an
MS for mud and snow. SeeTire Sidewall Labeling
on page 330for additional information.
{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,
CAUTION: (Continued)
CAUTION: (Continued)
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 365.
{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.
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6. Place the smaller jack hold-down nut in a safe
place for use when you put the compact
spare tire back into the trunk.
7. Remove the plastic sleeve from the stow bolt
extension rod. Secure the jack and road
wheel using the larger plastic retainer.
The compact spare tire is for temporary use only.
Replace the compact spare with a full-size tire
as soon as possible.
Compact Spare Tire
Although the compact spare tire was fully inated
when the vehicle was new, it can lose air after
a time. Check the ination pressure regularly.
It should be 60 psi (420 kPa).
After installing the compact spare on the vehicle,
stop as soon as possible and make sure the
spare tire is correctly inated. The compact spare
is made to perform well at speeds up to 65 mph
(105 km/h) for distances up to 3,000 miles(5 000 km), so you can nish your trip and have
the full-size tire repaired or replaced at your
convenience. Of course, it is best to replace the
spare with a full-size tire as soon as possible.
The spare tire will last longer and be in good
shape in case it is needed again.
Notice:When the compact spare is installed,
do not take your vehicle through an automatic
car wash with guide rails. The compact
spare can get caught on the rails. That can
damage the tire and wheel, and maybe
other parts of your vehicle.
Do not use the compact spare on other vehicles.
And do not mix the compact spare tire or
wheel with other wheels or tires. They will not t.
Keep the spare tire and its wheel together.
Notice:Tire chains will not t your compact
spare. Using them can damage your vehicle
and can damage the chains too. Do not use tire
chains on your compact spare.
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MaintenanceI— Use MaintenanceIif the CHG
OIL message comes on within 10 months since
the vehicle was purchased or MaintenanceIIwas
performed.MaintenanceII— Use MaintenanceIIif the
previous service performed was MaintenanceI.
Always use MaintenanceIIwhenever the message
comes on 10 months or more since the last
service or if the message has not come on at all
for one year.
Scheduled Maintenance
Service MaintenanceIMaintenanceII
Change engine oil and lter. SeeEngine Oil on page 283. Reset oil life system.
SeeEngine Oil Life System on page 288.An Emission Control Service.••
Visually check for any leaks or damage.See footnote (j).••
Inspect engine air cleaner lter. If necessary, replace lter. SeeEngine Air
Cleaner/Filter on page 290.See footnote (l).•
Rotate tires and check ination pressures and wear. SeeTire Inspection and
Rotation on page 339and “Tire Wear Inspection” inAt Least Once a Month on
page 398.••
Inspect brake system.See footnote (a).••
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