CHEVROLET CORVETTE 2004 5.G Owners Manual

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 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 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 inflated. The
maximum air pressure is molded onto the sidewall.
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 pounds
(68 kg). SeeLoading Your Vehicle on page 4-33.
Occupant Distribution:Designated seating positions.
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.
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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 and
shown on the tire placard. SeeInation - Tire Pressure
on page 5-62andLoading 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 5-65.
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 5-67.
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 inflation pressure. SeeLoading Your
Vehicle on page 4-33.
5-60

Extended Mobility Tires
(Except Z06)
Your vehicle, when new, had Goodyear Extended
Mobility Tires (EMT). There’s no spare tire, no tire
changing equipment and no place to store a tire in the
vehicle. Extended Mobility Tires perform so well
without any air that a Tire Pressure Monitor (TPM) is
used to alert you if a tire has lost pressure.
If a tire goes flat, you won’t need to stop on the side of
the road to change the tire. You can just keep on
driving. The shorter the distance you drive and the
slower the speed, the greater the chance that the tire will
not have to be replaced. If you drive on a deflated
EMT for 50 miles (80 km) or less and at speeds
of 55 mph (90 km/h) or less, there is a good chance that
the tire can be repaired. The tire can operate effectively
with no air pressure for up to 200 miles (320 km) at
speeds up to 55 mph (90 km/h), but the tire would then
have to be replaced. When a tire is filled with air, it
provides a cushion between the road and the wheel.
Because you won’t have this cushion when driving on a
deflated tire, try to avoid potholes that could damage
your wheel and require replacement of it.
Some road hazards can damage a tire beyond repair.
This damage could occur even before you’ve driven
on the tire in a deflated condition. When a tire has been
damaged, or if you’ve driven any distance on adeflated EMT, check with an authorized Goodyear EMT
Service Center to determine whether the tire can be
repaired or should be replaced. To maintain your
vehicle’s extended mobility feature, all replacement tires
must be Extended Mobility Tires. As soon as possible,
contact the nearest authorized GM or Goodyear
EMT servicing facility for inspection and repair or
replacement. To locate the nearest GM or Goodyear
EMT servicing facility, call Roadside Assistance.
For phone numbers and Roadside Assistance details
seeRoadside Assistance Program on page 7-6.
You may also contact Goodyear, for the nearest
authorized EMT servicing facility, by calling
1-800-789-9878.
{CAUTION:
Extended mobility tires are constructed
differently than other tires and could explode
during improper service. You or others could
be injured or killed if you attempt to repair,
replace, dismount, or mount a extended
mobility tire. Let only an authorized EMT
Service Center repair, replace, dismount and
mount extended mobility tires.
5-61

The valve stems on your extended mobility tires have
sensors that are part of the Tire Pressure Monitor
(TPM). SeeTire Pressure Monitor Operation
(Except Z06) on page 5-64. The TPM sensors contain
batteries which are designed to last for 10 years
under normal driving conditions. See your dealer if you
ever need to have a wheel replaced, or if the sensors
ever need replacement.
Notice:Using liquid sealants can damage the tire
valves and tire pressure monitor sensors in your
extended mobility tires. This damage would not be
covered by warranty. Don’t use liquid sealants
in your extended mobility tires.
If you feel that winter tires are needed for your driving
conditions, Goodyear Eagle M+S EMT tires are available
in your original equipment sizes from an authorized
Goodyear EMT retailer. These tires will improve snow
traction while maintaining your vehicle’s extended
mobility feature. When using winter tires on your vehicle,
be sure to use them on all four wheels. SeeBuying
New Tires on page 5-66.Ination - Tire Pressure
The tire and loading information label, shows the correct
inflation 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.
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.
How to Check
Use a good quality pocket-type gage to check tire
pressure. You can’t tell if your tires are properly inflated
simply by looking at them. Radial tires may look
properly inflated even when they are underinflated.
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. 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.
If your vehicle is equipped with the Tire Pressure
Monitor, you can check tire inflation pressures while
driving. After you’ve reached a speed of 15 mph
(24 kmh) or more, press and release the GAGES button
on the Driver Information Center (DIC) until the front
tire pressures are displayed. Then, press and release
the GAGES button for the rear tire pressures. If the
display doesn’t show tire pressure, or if the SERVICE
TIRE MON SYS message appears see your dealer
for service. For more information, seeTire Pressure
Monitor Operation (Except Z06) on page 5-64andDriver
Information Center (DIC) on page 3-48.
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Tire Pressure Monitor Operation
(Except Z06)
The Tire Pressure Monitor (TPM) has a sensor on each
road wheel that transmits to a receiver on the
instrument panel.
The system 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, and
(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, and (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.
If a tire’s inflation pressure is between 5 psi (35 kPa)
and 25 psi (170 kPa), you will see a message on
the Driver Information Center. This message will show
which tire is underinflated and two chimes will sound. An
example would be LOW TIRE PRESSURE-LR. This
would mean that the inflation pressure in your left rear
tire is between 5 psi (35 kPa) and 25 psi (170 kPa).
If the inflation pressure in the tire drops below
5 psi (35 kPa), the message would read FLAT TIRE-LR
and four chimes will sound. SeeDriver Information
Center (DIC) on page 3-48.
The TPM will also alert you if a tire’s pressure is higher
than 42 psi (290 kPa). The message will show which
tire is overinflated and two chimes will sound. An
example would be HIGH PRESSURE-LR. This would
mean that the inflation pressure in your left rear tire
is higher than 42 psi (290 kPa). SeeDriver Information
Center (DIC) on page 3-48.
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If a tire pressure message appears on the Driver
Information Center, stop as soon as you can. Have the
tire pressures checked and set to those shown on
your Tire-Loading Information label. SeeInation - Tire
Pressure on page 5-62.
{CAUTION:
When the LOW TIRE PRESSURE or FLAT TIRE
message is displayed on the Driver Information
Center, your vehicle’s handling capabilities will
be reduced during severe maneuvers. If you
drive too fast, you could lose control of your
vehicle. You or others could be injured. Don’t
drive over 55 mph (90 km/h) when the LOW
TIRE PRESSURE or FLAT TIRE message is
displayed. Drive cautiously, and check your
tire pressures as soon as you can.
Tire Rotation
The tires on your vehicle are different sizes front to rear.
Due to this, your tires should not be rotated. Each tire
and wheel should be used only in the position it is in.
When It Is Time for New Tires
One way to tell when it’s
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
can’t be repaired well because of the size or
location of the damage.
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Buying New Tires
To find out what kind and size of tires your vehicle
needs, look at the Tire and Loading Information label.
SeeLoading Your Vehicle on page 4-33, for an example
of the label and where it is located on your vehicle.
The tires installed on your vehicle when it was new had
a Tire Performance Criteria Specification (TPC Spec)
number on each tire’s sidewall. When you get new tires,
GM recommends that you get tires with that same
TPC Spec number. That way your vehicle will continue
to have tires that are designed to give proper
endurance, handling, load range, speed rating, traction,
ride, tire pressure monitoring system performance
and other things during normal service on your vehicle.
If your tires have an all-season tread design, the
TPC number will be followed by an “MS” (for mud
and snow).
If you ever replace your tires with those not having a
TPC Spec number, make sure they are the same size,
load range, speed rating and construction type (bias,
bias-belted or radial) as your original tires.{CAUTION:
Mixing tires could cause you to lose control
while driving. If you mix tires of different sizes
(other than those originally installed on your
vehicle) or types (radial and bias-belted tires),
the vehicle may not handle properly, and you
could have a crash. Using tires of different
sizes (other than those originally installed on
your vehicle) may also cause damage to your
vehicle. Be sure to use the correct size and
type tires on all four wheels.
If your vehicle is equipped with Extended Mobility Tires
and you feel that winter tires are needed, see
Extended Mobility Tires (Except Z06) on page 5-61.
{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.
5-66

Uniform Tire Quality Grading
Quality grades can be found where applicable on the
tire sidewall between tread shoulder and maximum
section width. For example:
Treadwear 200 Traction AA Temperature A
The following information relates to the system
developed by the United States National Highway
Traffic Safety Administration, which grades tires by
treadwear, traction and temperature performance. (This
applies only to vehicles sold in the United States.)
The grades are molded on the sidewalls of most
passenger car tires. The Uniform Tire Quality Grading
system does not apply to deep tread, winter-type
snow tires, space-saver or temporary use spare tires,
tires with nominal rim diameters of 10 to 12 inches
(25 to 30 cm), or to some limited-production tires.
While the tires available on General Motors passenger
cars and light trucks may vary with respect to these
grades, they must also conform to federal safety
requirements and additional General Motors Tire
Performance Criteria (TPC) standards.
Treadwear
The treadwear grade is a comparative rating based on
the wear rate of the tire when tested under controlled
conditions on a specified government test course.
For example, a tire graded 150 would wear one and
a half (1.5) times as well on the government course as
a tire graded 100. The relative performance of tires
depends upon the actual conditions of their use,
however, and may depart significantly from the norm
due to variations in driving habits, service practices and
differences in road characteristics and climate.
Traction – AA, A, B, C
The traction grades, from highest to lowest, are AA, A,
B, and C. Those grades represent the tire’s ability
to stop on wet pavement as measured under controlled
conditions on specified government test surfaces of
asphalt and concrete. A tire marked C may have poor
traction performance. Warning: The traction grade
assigned to this tire is based on straight-ahead braking
traction tests, and does not include acceleration,
cornering, hydroplaning, or peak traction characteristics.
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Temperature – A, B, C
The temperature grades are A (the highest), B, and C,
representing the tire’s resistance to the generation
of heat and its ability to dissipate heat when tested
under controlled conditions on a specified indoor
laboratory test wheel. Sustained high temperature can
cause the material of the tire to degenerate and
reduce tire life, and excessive temperature can lead to
sudden tire failure. The grade C corresponds to a
level of performance which all passenger car tires must
meet under the Federal Motor Vehicle Safety Standard
No. 109. Grades B and A represent higher levels of
performance on the laboratory test wheel than the
minimum required by law.
Warning: The temperature grade for this tire is
established for a tire that is properly inflated and not
overloaded. Excessive speed, underinflation, or
excessive loading, either separately or in combination,
can cause heat buildup and possible tire failure.
Wheel Alignment and Tire Balance
The wheels on your vehicle were aligned and balanced
carefully at the factory to give you the longest tire life
and best overall performance.
Scheduled wheel alignment and wheel balancing are
not needed. However, if you notice unusual tire wear or
your vehicle pulling one way or the other, the alignment
may need to be reset. If you notice your vehicle
vibrating when driving on a smooth road, your wheels
may need to be rebalanced.
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 if any of these conditions exist.
Your dealer 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.
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