2008 CHEVROLET CORVETTE service

If your vehicle has the 7.0L V8 engine (VIN Code E),
use premium unleaded gasoline with a posted octane
rating of 91 or higher. For best performance, use
premium unleaded gasoline with a posted octane
rating of 93. In an emergency, you can use regular
unleaded gasoline with an octane rating of 87 or higher.
If 87 octane fuel is used, do not perform any aggressive
driving maneuvers such as wide open throttle
applications. You might also hear audible spark knock
during acceleration. Rell the tank with premium fuel
as soon as possible to avoid damaging the engine.
If you are using gasoline rated at 91 octane or higher
and you hear heavy knocking, the engine needs service.
Gasoline Specications
At a minimum, gasoline should meet ASTM specication
D 4814 in the United States or CAN/CGSB-3.5 or
3.511 in Canada. Some gasolines contain an
octane-enhancing additive called methylcyclopentadienyl
manganese tricarbonyl (MMT). We recommend
against the use of gasolines containing MMT.
SeeAdditives on page 5-7for additional information.
California Fuel
If your vehicle is certied to meet California Emissions
Standards, it is designed to operate on fuels that
meet California specications. See the underhood
emission control label. If this fuel is not available
in states adopting California emissions standards, your
vehicle will operate satisfactorily on fuels meeting
federal specications, but emission control system
performance might be affected. The malfunction
indicator lamp could turn on and your vehicle might fail
a smog-check test. SeeMalfunction Indicator Lamp
on page 3-45. If this occurs, return to your authorized
dealer/retailer for diagnosis. If it is determined that
the condition is caused by the type of fuel used, repairs
might not be covered by the vehicle warranty.
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Additives
To provide cleaner air, all gasolines in the United States
are now required to contain additives that help prevent
engine and fuel system deposits from forming, allowing
the emission control system to work properly. In most
cases, you should not have to add anything to the fuel.
However, some gasolines contain only the minimum
amount of additive required to meet U.S. Environmental
Protection Agency regulations. To help keep fuel injectors
and intake valves clean, or if your vehicle experiences
problems due to dirty injectors or valves, look for gasoline
that is advertised as TOP TIER Detergent Gasoline. Also,
your dealer/retailer has additives that will help correct and
prevent most deposit-related problems.
Gasolines containing oxygenates, such as ethers and
ethanol, and reformulated gasolines might be available in
your area. We recommend that you use these gasolines,
if they comply with the specications described earlier.
However, E85 (85% ethanol) and other fuels containing
more than 10% ethanol must not be used in vehicles that
were not designed for those fuels.Notice:Your vehicle was not designed for fuel that
contains methanol. Do not use fuel containing
methanol. It can corrode metal parts in the fuel
system and also damage plastic and rubber parts.
That damage would not be covered under your
warranty.
Some gasolines that are not reformulated for low
emissions can contain an octane-enhancing additive
called methylcyclopentadienyl manganese tricarbonyl
(MMT); ask the attendant where you buy gasoline
whether the fuel contains MMT. We recommend against
the use of such gasolines. Fuels containing MMT can
reduce the life of spark plugs and the performance
of the emission control system could be affected.
The malfunction indicator lamp might turn on. If this
occurs, return to your dealer/retailer for service.
5-7

Substitute Engine Oil: When adding oil to maintain
engine oil level, oil meeting GM Standard GM4718M
may not be available. You can add substitute oil
designated SAE 5W-30 with the starburst symbol at all
temperatures. Substitute oil not meeting GM Standard
GM4718M should not be used for an oil change.
Engine Oil Additives
Do not add anything to the oil. The recommended oils
with the starburst symbol that meet GM Standard
GM4718M are all you need for good performance and
engine protection.
Engine Oil Life System
When to Change Engine Oil
Your vehicle has a computer that lets you know when
to change the engine oil and lter. This is based on
engine revolutions and engine temperature, and not on
mileage. Based on driving conditions, the mileage at
which an oil change will be indicated can vary
considerably. For the oil life system to work properly,
you must reset the system every time the oil is changed.Z06 models have a racetrack-ready dry sump engine
lubrication system. This high-performance system
operates differently than a standard engine lubrication
system and requires a special procedure when changing
the engine oil and lter. SeeEngine Oil on page 5-17.
When the system has calculated that oil life has been
diminished, it will indicate that an oil change is necessary.
A CHANGE ENGINE OIL message will come on. Change
the oil as soon as possible within the next 600 miles
(1 000 km). It is possible that, if you are driving under the
best conditions, the oil life system might not indicate that
an oil change is necessary for over a year. However, the
engine oil and lter must be changed at least once a year
and at this time the system must be reset. Your dealer/
retailer has trained service people who will perform this
work using genuine parts and reset the system. It is also
important to check the oil regularly and keep it at the
proper level.
If the system is ever reset accidentally, you must
change the oil at 3,000 miles (5 000 km) since your
last oil change. Remember to reset the oil life system
whenever the oil is changed.
5-23

How to Reset the Engine Oil Life
System
The Engine Oil Life System calculates when to change
the engine oil and lter based on vehicle use.
Whenever the oil is changed, reset the system so it can
calculate when the next oil change is required. If a
situation occurs where you change the oil prior
to a CHANGE ENGINE OIL message being turned on,
reset the system.
To reset the CHANGE ENGINE OIL message after an
oil change:
1. Press the TRIP button so the OIL LIFE percentage
is displayed.
2. Press RESET and hold for two seconds. OIL LIFE
REMAINING 100% will appear.
If the CHANGE ENGINE OIL message comes back on
when you start your vehicle, the engine oil life system
has not reset. Repeat the procedure.
What to Do with Used Oil
Used engine oil contains certain elements that can be
unhealthy for your skin and could even cause cancer.
Do not let used oil stay on your skin for very long. Clean
your skin and nails with soap and water, or a good
hand cleaner. Wash or properly dispose of clothing or
rags containing used engine oil. See the manufacturer’s
warnings about the use and disposal of oil products.
Used oil can be a threat to the environment. If you
change your own oil, be sure to drain all the oil from
the lter before disposal. Never dispose of oil by putting
it in the trash, pouring it on the ground, into sewers,
or into streams or bodies of water. Instead, recycle it by
taking it to a place that collects used oil. If you have
a problem properly disposing of used oil, ask your
dealer/retailer, a service station, or a local recycling
center for help.
5-24

Automatic Transmission Fluid
How to Check Automatic Transmission
Fluid
It is not necessary to check the transmission uid level.
A transmission uid leak is the only reason for uid
loss. If a leak occurs, take the vehicle to the dealer/
retailer service department and have it repaired as soon
as possible.
There is a special procedure for checking and changing
the transmission uid. Because this procedure is difficult,
you should have this done at the dealer/retailer service
department. Contact your dealer/retailer for additional
information or the procedure can be found in the service
manual. To purchase a service manual, seeService
Publications Ordering Information on page 7-17.
Notice:Use of the incorrect automatic transmission
uid may damage your vehicle, and the damages
may not be covered by your warranty. Always
use the automatic transmission uid listed in
Recommended Fluids and Lubricants on page 6-12.Change the uid and lter at the intervals listed in
Additional Required Services on page 6-6, and be sure
to use the uid listed inRecommended Fluids and
Lubricants on page 6-12.Manual Transmission Fluid
It is not necessary to check the manual transmission
uid level. A transmission uid leak is the only reason
for uid loss. If a leak occurs, take the vehicle to the
dealer/retailer service department and have it repaired
as soon as possible. SeeRecommended Fluids and
Lubricants on page 6-12for the proper uid to use.
Hydraulic Clutch
It is not necessary to regularly check clutch uid unless
you suspect there is a leak in the system. Adding
uid will not correct a leak. A uid loss in this system
could indicate a problem. Have the system inspected
and repaired.
5-27

When to Check and What to Use
The hydraulic clutch uid
reservoir cap has this
symbol on it. SeeEngine
Compartment Overview
on page 5-14for reservoir
location.
Refer to the Maintenance Schedule for the proper uid
to use. SeeRecommended Fluids and Lubricants
on page 6-12. The uid requires changing every
two years. SeeAdditional Required Services on
page 6-6.
How to Check and Add Fluid
Visually check the clutch uid reservoir to make sure
the uid level is at the MIN (Minimum) line on the side of
the reservoir. The hydraulic clutch uid system should
be kept closed and sealed. Do not remove the cap
to check the uid level or to top-off the uid level.
Remove the cap only when necessary to add the
proper uid until the level reaches the MIN line.
Engine Coolant
The cooling system in your vehicle is lled with
DEX-COOL®engine coolant. This coolant is designed
to remain in your vehicle for ve years or 150,000 miles
(240 000 km), whichever occurs rst, if you add only
DEX-COOL
®extended life coolant.
The following explains your cooling system and how to
add coolant when it is low. If you have a problem
with engine overheating, seeEngine Overheating on
page 5-31.
A 50/50 mixture of clean, drinkable water and
DEX-COOL
®coolant will:
Give freezing protection down to−34°F (−37°C).
Give boiling protection up to 265°F (129°C).
Protect against rust and corrosion.
Help keep the proper engine temperature.
Let the warning lights and gages work as they
should.
Notice:Using coolant other than DEX-COOL
®can
cause premature engine, heater core, or radiator
corrosion. In addition, the engine coolant may
require changing sooner, at the rst maintenance
service after each 30,000 miles (50 000 km) or
24 months, whichever occurs rst. Any repairs would
not be covered by the vehicle warranty. Always use
DEX-COOL
®(silicate-free) coolant in the vehicle.
5-28

If you no longer have the overheat warning, you can
drive. Just to be safe, drive slower for about 10 minutes.
If the warning does not come back on, you can drive
normally.
If the warning continues and you are not stopped, pull
over, stop, and park your vehicle right away.
If there is still no sign of steam, you can idle the engine
for three minutes while you are parked. If you still
have the warning, turn off the engine and get everyone
out of the vehicle until it cools down. Also, see
“Overheated Engine Protection Operating Mode” later in
this section.
You may decide not to lift the hood but to get service
help right away.Overheated Engine Protection
Operating Mode
If an overheated engine condition exists and the
messages COOLANT OVER TEMPERATURE and
REDUCED ENGINE POWER are displayed, along with
the Check Engine light, an overheat protection mode
which alternates ring groups of cylinders helps prevent
engine damage. In this mode, you will notice a loss
in power and engine performance. This operating mode
allows your vehicle to be driven to a safe place in an
emergency; you may drive up to 50 miles (80 km).
Notice:After driving in the overheated engine
protection operating mode, to avoid engine damage,
allow the engine to cool before attempting any
repair. The engine oil will be severely degraded.
Repair the cause of coolant loss, change the oil
and reset the oil life system. SeeEngine Oil
on page 5-17.
5-33

{CAUTION:
Heater and radiator hoses, and other engine
parts, can be very hot. Do not touch them.
If you do, you can be burned.
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 fan is running.
If the engine is overheating, the fan should be running.
If it is not, your vehicle needs service.Notice:Engine damage from running your engine
without coolant is not covered by your warranty.
SeeOverheated Engine Protection Operating Mode
on page 5-33for information on driving to a safe
place in an emergency.
Notice:Using coolant other than DEX-COOL®can
cause premature engine, heater core, or radiator
corrosion. In addition, the engine coolant could
require changing sooner, at 30,000 miles (50 000 km)
or 24 months, whichever occurs rst. Any repairs
would not be covered by the vehicle warranty.
Always use DEX-COOL
®(silicate-free) coolant in
the vehicle.
5-35