2004 PONTIAC BONNEVILLE tire pressure

(C) Aspect Ratio:A two-digit number that indicates the
tire height-to-width measurements. For example, if
the tire size aspect ratio is “70,” as shown in item “C” of
the illustration, it would mean that the tire’s sidewall
is 70% 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 the speed rating of a tire. The load
range represents the load carrying 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”.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.
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Cold Ination Pressure:The amount of air pressure in
a tire, measured in pounds per square inch (psi) before a
tire has built up heat from driving. SeeInation - Tire
Pressure on page 5-67.
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 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 4-33.
GAWR FRT:Gross Axle Weight Rating for the front
axle, seeLoading Your Vehicle on page 4-33.
GAWR RR:Gross Axle Weight Rating for the rear axle,
seeLoading Your Vehicle on page 4-33.
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.
There are 6.9 kPa’s to one psi.
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 pounds
(68 kg). SeeLoading Your Vehicle on page 4-33.
Occupant Distribution:Designated seating positions.
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Outward Facing Sidewall:The side of a 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 and
shown on the tire placard. SeeInation - Tire Pressure
on page 5-67andLoading Your Vehicle on page 4-33.
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 2/32 inch of tread remains. SeeWhen It
Is Time for New Tires on page 5-72.
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 5-74.
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 4-33.
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 original equipment tire size
and recommended ination pressure. SeeLoading Your
Vehicle on page 4-33.
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Ination - Tire Pressure
The Tire and Loading Information label, shows the correct
ination 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 1 mile (1.6 km). See
Loading Your Vehicle on page 4-33, for the location of
your vehicle’s tire and loading information label.
If you’ll be driving at high speeds (e.g., speeds of
100 mph (160 km/h) or higher), where it is legal, set the
cold ination pressure to the maximum ination pressure
shown on the tire sidewall, or to 35 psi (244 kPa),
whichever is lower. See the example below. When you
end this high–speed driving, return to the cold ination
pressure shown on the Tire–Loading Information label.
Example:
You’ll nd maximum load and ination pressure molded
on the tire’s sidewall, in small letters near the rim
ange. It will read something like this: Maximum load
690 kg (1521 lbs) 300 kPa (44 psi) Max. Press.
For this example, you would set the ination pressure
for high-speed driving at 35 psi (244 kPa).Notice:Don’t let anyone tell you that underination
or overination is all right. It’s not. If your tires
don’t have enough air (underination), you can get
the following:
Too much exing
Too much heat
Tire overloading
Bad wear
Bad handling
Bad fuel economy
If your tires have too much air (overination), you
can get the following:
Unusual wear
Bad handling
Rough ride
Needless damage from road hazards
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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 inated
simply by looking at them. Radial tires may look
properly inated even when they’re underinated.
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. Be sure to put the valve caps
back on the valve stems. They help prevent leaks by
keeping out dirt and moisture.
If you overll the tire, release air by pushing on the
metal stem in the center of the tire valve. Recheck 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.
Check Tire Pressure System
The check tire pressure system can alert you to a large
change in the pressure of one tire. The system will not
alert you before you drive that a tire is low or at. You
must begin driving before the system will work properly.
The CHECK TIRE PRESSURE message will appear on
the Driver Information Center (DIC) or the system
monitor TIRE PRESS light will come on if pressure
difference (low pressure) is detected in one tire.
The check tire pressure system may not alert you if:
More than one tire is low.
The vehicle is moving faster than 65 mph (105 km/h).
The system is not yet calibrated.
The compact spare tire is installed.
The tire treadwear is uneven.
Tire chains are being used.
The vehicle is being driven on a rough or frozen road.
If the anti-lock brake system warning light comes on,
the check tire pressure system may not be working
properly. See your dealer for service. Also, see
Anti-Lock Brake System Warning Light on page 3-44.
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The check tire pressure system detects differences in
tire rotation speeds that are caused by changes in
tire pressure. The system can alert you about a
low tire — but it does not replace normal tire
maintenance. SeeTires on page 5-58.
When the CHECK TIRE PRESSURE message appears
on the Driver Information Center (DIC) or the systems
monitor TIRE PRESS light comes on, you should stop as
soon as you can and check all your tires for damage. If a
tire is at, seeIf a Tire Goes Flat on page 5-79. Also
check the tire pressure in all four tires as soon as you
can. SeeInation - Tire Pressure on page 5-67.
Any time you adjust a tire’s pressure or have one or more
tires repaired or replaced, you will need to reset
(calibrate) the check tire pressure system. You will also
need to reset the system whenever you rotate the tires,
buy new tires and install or remove the compact spare.Do not reset the check tire pressure system without rst
correcting the cause of the problem and checking
and adjusting the pressure in all four tires. If you reset
the system when the tire pressures are incorrect,
the check tire pressure system will not work properly
and may not alert you when a tire is low or high.
To reset (calibrate) the system with a Driver Information
Center (DIC):
1. Turn the ignition switch to ON.
2. Using the MODE and SELECT buttons, change the
DIC to display TIRE PRESSURE.
3. Press and hold the RESET button for about ve
seconds.
4. The display should change to read TIRE
PRESSURE RESET. If TIRE PRESSURE RESET
does not appear on the display after about ve
seconds, see your dealer for service.
5. When you release the button after seeing the TIRE
PRESSURE RESET message, the display will
change to read TIRE PRESSURE NORMAL.
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When rotating your tires, always use the correct rotation
pattern shown here.
Don’t 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.
Reset the check tire pressure system, if equipped. See
Check Tire Pressure System on page 5-68.
Make certain that all wheel nuts are properly tightened.
See “Wheel Nut Torque” underCapacities and
Specications on page 5-109.
{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 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. See “Changing a Flat
Tire” in the Index.
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Compact Spare Tire
Although the compact spare tire was fully inated when
your 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 your vehicle, you
should stop as soon as possible and make sure
your 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 your full-size
tire repaired or replaced where you want. You must
calibrate the Check Tire Pressure System after installing
or removing the compact spare. SeeCheck Tire
Pressure System on page 5-68. Of course, it’s best to
replace your spare with a full-size tire as soon as
you can. Your spare will last longer and be in good
shape in case you need it again.Notice:When the compact spare is installed, don’t
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.
Don’t use your compact spare on other vehicles.
And don’t mix your compact spare tire or wheel with
other wheels or tires. They won’t t. Keep your compact
spare tire and its wheel together.
Notice:Tire chains won’t t your compact spare.
Using them can damage your vehicle and can
damage the chains too. Don’t use tire chains on
your compact spare.
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