service CHEVROLET CORVETTE 2004 5.G Service Manual

The coolant level should be at or above the FULL COLD
mark. If it is not, you may have a leak at the pressure cap
or in the radiator hoses, heater hoses, radiator, water
pump or somewhere else in the cooling system.
{CAUTION:
Heater and radiator hoses, and other engine
parts, can be very hot. Do not touch them. If
you do, you can be burned.
CAUTION: (Continued)
CAUTION: (Continued)
Do not run the engine if there is a leak. If you
run the engine, it could lose all coolant. That
could cause an engine re, and you could be
burned. Get any leak xed before you drive the
vehicle.
If there seems to be no leak, with the engine on, check
to see if the electric engine cooling fans are running.
If the engine is overheating, both fans should be
running. If they are not, your vehicle needs service.
Notice:Engine damage from running your engine
without coolant is not covered by your warranty. See
“Overheated Engine Protection Operating Mode”
in the Index for information on driving to a safe
place in an emergency.
Notice:Using coolant other than DEX-COOL
®may
cause premature engine, heater core or radiator
corrosion. In addition, the engine coolant may
require changing sooner, at 30,000 miles (50 000 km)
or 24 months, whichever occurs rst. Any repairs
would not be covered by your warranty. Always use
DEX-COOL
®(silicate-free) coolant in your vehicle.
5-30

Brake Wear
Your vehicle has four-wheel disc brakes.
Disc brake pads have built-in wear indicators that make
a high-pitched warning sound when the brake pads
are worn and new pads are needed. The sound
may come and go or be heard all the time your vehicle
is moving (except when you are pushing on the
brake pedal firmly).
{CAUTION:
The brake wear warning sound means that
soon your brakes will not work well. That
could lead to an accident. When you hear the
brake wear warning sound, have your vehicle
serviced.
Z06 models are equipped with high performance front
brake linings designed for improved brake performance
under severe use. They will normally exhibit some
low speed noise and you may notice an increase in the
amount of brake dust.Notice:Continuing to drive with worn-out brake
pads could result in costly brake repair.
Some driving conditions or climates may cause a brake
squeal when the brakes are first applied or lightly
applied. This does not mean something is wrong with
your brakes.
Brake linings should always be replaced as complete
axle sets.
Brake Pedal Travel
See your dealer if the brake pedal does not return to
normal height, or if there is a rapid increase in
pedal travel. This could be a sign of brake trouble.
Brake Adjustment
As you make brake stops, your disc brakes
automatically adjust for wear.
5-39

Replacing Brake System Parts
The braking system on a vehicle is complex. Its many
parts have to be of top quality and work well together if
the vehicle is to have really good braking. Your
vehicle was designed and tested with top-quality GM
brake parts. When you replace parts of your braking
system — for example, when your brake linings
wear down and you need new ones put in — be sure
you get new approved GM replacement parts. If you do
not, your brakes may no longer work properly. For
example, if someone puts in brake linings that are wrong
for your vehicle, the balance between your front and
rear brakes can change — for the worse. The braking
performance you have come to expect can change
in many other ways if someone puts in the wrong
replacement brake parts.
Battery
Your new vehicle comes with a maintenance free
ACDelco®battery. When it is time for a new battery, get
one that has the replacement number shown on the
original battery’s label. We recommend an ACDelco
®
battery.
For battery replacement, see your dealer or the service
manual. To purchase a service manual, seeService
and Owner PublicationsinService Publications Ordering
Information on page 7-11.
Warning:Battery posts, terminals and related
accessories contain lead and lead compounds,
chemicals known to the State of California to cause
cancer and reproductive harm. Wash hands after
handling.
5-40

8. Now connect the black
negative (−) cable to
the negative (−)
terminal of the good
battery. Use a remote
negative (−) terminal
if the vehicle has one.
Do not let the other end touch anything until the
next step. The other end of the negative (−) cable
does not go to the dead battery. It goes to a
heavy, unpainted metal engine part or to a remote
negative (−) terminal on the vehicle with the
dead battery.9. Connect the other end of the negative (−) cable at
least 18 inches (45 cm) away from the dead battery,
but not near engine parts that move. The electrical
connection is just as good there, and the chance
of sparks getting back to the battery is much less.
10. Now start the vehicle with the good battery and run
the engine for a while.
11. Try to start the vehicle that had the dead battery. If
it will not start after a few tries, it probably needs
service.
5-45

Bulb Replacement
For the proper type of replacement bulb, seeBulb
Replacement on page 5-48.
For any bulb changing procedure not listed in this
section, contact your dealer’s service department.
Halogen Bulbs
{CAUTION:
Halogen bulbs have pressurized gas inside and
can burst if you drop or scratch the bulb. You or
others could be injured. Be sure to read and
follow the instructions on the bulb package.
Headlamps
1. The headlamp doors need to be halfway open.
Turn the headlamps on, then quickly back to the
parking lamps setting. You may have to do
this a few times to get the half-open position.
You can also open the headlamp doors manually
by turning the adjuster counterclockwise.
5-48

Tires
Your new vehicle comes with high-quality tires made by
a leading tire manufacturer. If you ever have questions
about your tire warranty and where to obtain service,
see your GM Warranty booklet for details. For additional
information refer to the tire manufacturer’s booklet
included with your vehicle’s Owner’s Manual.
{CAUTION:
Poorly maintained and improperly used tires
are dangerous.
Overloading your tires can cause
overheating as a result of too much
friction. You could have an air-out and a
serious accident. See “Loading Your
Vehicle” in the Index.
CAUTION: (Continued)
CAUTION: (Continued)

Underinated tires pose the same danger
as overloaded tires. The resulting accident
could cause serious injury. Check all tires
frequently to maintain the recommended
pressure. Tire pressure should be checked
when your tires are cold.
Overinated tires are more likely to be
cut, punctured or broken by a sudden
impact — such as when you hit a pothole.
Keep tires at the recommended pressure.
Worn, old tires can cause accidents. If
your tread is badly worn, or if your tires
have been damaged, replace them.
Tire Sidewall Labeling
Useful information about a tire is molded into its
sidewall. The following illustration shows an example of
a passenger car tire sidewall.
5-55

A. Tire Size
B. Tire Performance Criteria Specification (TPC Spec)
C. Department of Transportation (DOT)
D. Tire Identification Number (TIN)
E. Tire Ply Material
F. Uniform Tire Quality Grading (UTQG)
G. Maximum Cold Inflation Load Limit
(A) Tire Size:The tire size code is a combination of
letters and numbers used to define a particular
tire’s width, height, aspect ratio, construction type and
service description. See the “Tire Size ” illustration later
in this section for more detail.
(B) Tire Performance Criteria Specication (TPC
Spec):Original equipment tires designed to GM’s
specific tire performance criteria have a TPC
specification code molded onto the sidewall. GM’s TPC
specifications meet or exceed all federal safety
guidelines.
(C) Department of Transportation (DOT):The
Department of Transportation (DOT) code indicates that
the tire is in compliance with the U.S. Department of
Transportation Motor Vehicle Safety Standards.
5-56

(D) Tire Identication Number (TIN):The letters and
numbers following DOT code are 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.
(E) Tire Ply Material:The type of cord and number of
plies in the sidewall and under the tread.
(F) Uniform Tire Quality Grading (UTQG):Tire
manufacturers are required to grade tires based on three
performance factors: treadwear, traction and
temperature resistance. For more information see
Uniform Tire Quality Grading on page 5-67.
(G) Maximum Cold Ination Load Limit:Maximum
load that can be carried and the maximum pressure
needed to support that load. For more information on
recommended tire pressure seeInation - Tire Pressure
on page 5-62andLoading Your Vehicle on page 4-33.Tire Size Codes
The following illustration shows an example of a typical
passenger car tire size.
A. P-Metric Tire
B. Tire Width
C. Aspect RatioD. Construction Code
E. Rim Diameter
F. Service Description
(A) 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.
5-57

(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
certified to carry. The load index can range from 1 to
279. 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, 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 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 5-62.
5-58

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