tire pressure CHEVROLET OPTRA 5 2007 1.G User Guide

(B) Tire Ply Material:The type of cord and
number of plies in the sidewall and under the tread.
(C) Tire Identication Number (TIN):The Tire
Identification 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.
(D) Maximum Cold Ination Load
Limit:Maximum load that can be carried and
the maximum pressure needed to support
that load. SeeCompact Spare Tire on page 334
andLoading Your Vehicle on page 236.
(E) Tire Ination:The temporary use tire or
compact spare tire should be inflated to 60 psi
(420 kPa). For more information on tire pressure
and inflation seeInflation - Tire Pressure on
page 311.
(F) Tire Size:A combination of letters and
numbers define a tire’s width, height, aspect ratio,
construction type and service description.
The letter T as the first character in the tire size
means the tire is for temporary use only.Tire Size
The following illustration shows an example of a
typical passenger car tire size.
(A) Passenger (P-Metric) Tire:The United States
version of a metric tire sizing system. The letter P
as the first 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.
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(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 carry
capacity a tire is certified to carry. The speed
rating is the maximum speed a tire is certified 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/transaxle, 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.
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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. SeeInflation - Tire Pressure on
page 311.
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 Identification 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 236.GAWR FRT:Gross Axle Weight Rating for the
front axle. SeeLoading Your Vehicle on page 236.
GAWR RR:Gross Axle Weight Rating for the
rear axle. SeeLoading Your Vehicle on page 236.
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 inflated.
The maximum air pressure is molded onto the
sidewall.
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Maximum Load Rating:The load rating for a tire
at the maximum permissible inflation 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 236.
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 inflation
pressure as shown on the tire placard.
SeeInflation - Tire Pressure on page 311and
Loading Your Vehicle on page 236.
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.
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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 317.
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 320.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 236.
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 inflation pressure. See “Tire and
Loading Information Label” underLoading
Your Vehicle on page 236.
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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 vehicle specific tire and loading information
label is attached to your vehicle. This label shows
your vehicle’s original equipment tires and the
correct inflation pressures for your tires when they
are cold. The recommended cold tire inflation
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 236. 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. For
additional information regarding the compact spare
tire, seeCompact Spare Tire on page 334.
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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 inflated simply by looking at them. Radial
tires may look properly inflated even when they
are under-inflated. Check the tire’s inflation
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 firmly onto the valve to
get a pressure measurement. If the cold tire
inflation pressure matches the recommended
pressure on the Tire and Loading Information
label, no further adjustment is necessary. If the
inflation pressure is low, add air until you reach
the recommended amount.
If you overfill 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.
Tire Pressure Monitor System
The Tire Pressure Monitor System (TPMS) uses
radio and sensor technology to check tire pressure
levels. If your vehicle has this feature, sensors
are mounted onto each tire and wheel assembly,
except for the spare tire. The TPMS sensors
monitor the air pressure in your vehicle’s tires and
transmit tire pressure readings to a receiver
located in the vehicle.
Each tire, including the spare (if provided), should
be checked monthly when cold and inflated to
the inflation pressure recommended by the vehicle
manufacturer on the vehicle placard or tire
inflation pressure label. (If your vehicle has tires of
a different size than the size indicated on the
vehicle placard or tire inflation pressure label,
you should determine the proper tire inflation
pressure for those tires.)
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As an added safety
feature, your vehicle
has been equipped
with a tire pressure
monitoring system
(TPMS) that illuminates
a low tire pressure
telltale when one
or more of your tires
is significantly
under-inflated.
Accordingly, when the low tire pressure telltale
illuminates, you should stop and check your tires
as soon as possible, and inflate them to the
proper pressure. Driving on a significantly
under-inflated tire causes the tire to overheat and
can lead to tire failure. Under-inflation also
reduces fuel efficiency and tire tread life, and may
affect the vehicle’s handling and stopping ability.
Please note that the TPMS is not a substitute for
proper tire maintenance, and it is the driver’s
responsibility to maintain correct tire pressure, even
if under-inflation has not reached the level to trigger
illumination of the TPMS low tire pressure telltale.Your vehicle has also been equipped with a
TPMS malfunction indicator to indicate when the
system is not operating properly. The TPMS
malfunction indicator is combined with the low tire
pressure telltale. When the system detects a
malfunction, the telltale will flash for approximately
one minute and then remain continuously
illuminated. This sequence will continue upon
subsequent vehicle start-ups as long as the
malfunction exists.
When the malfunction indicator is illuminated, the
system may not be able to detect or signal low
tire pressure as intended. TPMS malfunctions may
occur for a variety of reasons, including the
installation of replacement or alternate tires or
wheels on the vehicle that prevent the TPMS from
functioning properly. Always check the TPMS
malfunction telltale after replacing one or more
tires or wheels on your vehicle to ensure that the
replacement or alternate tires and wheels allow
the TPMS to continue to function properly.
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When a low tire pressure condition is detected,
the TPMS illuminates the low tire pressure warning
symbol on the instrument panel cluster.
The low tire pressure warning symbol comes on at
each ignition cycle until the tires are inflated to
the correct inflation pressure.
The tire pressure warning light may come on in
cool weather when the vehicle is first started, and
then turn off as you start to drive. This could
be an early indicator that the tire pressures are
getting low and need to be inflated to the
proper pressure.
A Tire and Loading Information label, attached to
your vehicle, shows the size of your vehicle’s
original equipment tires and the correct inflation
pressure for your vehicle’s tires when they
are cold. SeeLoading Your Vehicle on page 236,
for an example of the tire information label and
its location on your vehicle. Also seeInflation - Tire
Pressure on page 311.Your vehicle’s TPMS system can warn you about
a low tire pressure condition but it does not
replace normal tire maintenance. SeeTire
Inspection and Rotation on page 316andTires
on page 303.
Notice:Do not use a tire sealant if your
vehicle has Tire Pressure Monitors. The liquid
sealant can damage the tire pressure monitor
sensors.
The TPMS will not function properly if one or more
of the TPMS sensors are missing or inoperable.
See your dealer for service if all TPMS sensors are
installed and the low tire pressure warning light
comes on and stays on.
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TPMS Sensor Identication Codes
Each TPMS sensor has a unique identification
code. Any time you replace one or more of
the TPMS sensors or rotate the vehicle’s tires, the
identification codes need to be matched to the
new tire/wheel position. The sensors are matched,
to the tire/wheel positions, in the following order:
driver side front tire, passenger side front tire,
passenger side rear tire, and driver side rear tire
using a TPMS diagnostic tool. See your dealer
for service.
Federal Communications Commission
(FCC) and Industry and Science Canada
The Tire Pressure Monitor System (TPMS)
operates on a radio frequency subject to Federal
Communications Commission (FCC) Rules
and with Industry and Science Canada.This device complies with Part 15 of the FCC
Rules. Operation is subject to the following
two conditions:
1. This device may not cause harmful
interference.
2. This device must accept any interference
received, including interference that may
cause undesired operation.
This device complies with RSS-210 of Industry
and Science Canada. Operation is subject to the
following two conditions:
1. This device may not cause interference.
2. This device must accept any interference
received, including interference that may
cause undesired operation of the device.
Changes or modifications to this system by other
than an authorized service facility could void
authorization to use this equipment.
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