oil viscosity CHEVROLET CORVETTE 2004 5.G Owners Manual

Emissions Inspection and Maintenance
Programs
Some state/provincial and local governments have or
may begin programs to inspect the emission control
equipment on your vehicle. Failure to pass this
inspection could prevent you from getting a vehicle
registration.
Here are some things you need to know to help your
vehicle pass an inspection:
Your vehicle will not pass this inspection if the CHECK
ENGINE light is on or not working properly.
Your vehicle will not pass this inspection if the OBD
(on-board diagnostic) system determines that critical
emission control systems have not been completely
diagnosed by the system. The vehicle would be
considered not ready for inspection. This can happen if
you have recently replaced your battery or if your
battery has run down. The diagnostic system is
designed to evaluate critical emission control systems
during normal driving. This may take several days
of routine driving. If you have done this and your vehicle
still does not pass the inspection for lack of OBD
system readiness, your GM dealer can prepare the
vehicle for inspection.
Engine Oil Pressure Gage
The engine oil pressure gage shows the engine oil
pressure in psi (pounds per square inch) or kPa
(kilopascals) when the engine is running.
Oil pressure should be 20 to 80 psi (140 to 550 kPa). In
certain situations such as long, extended idles on hot
days, it could read as low as 6 psi (40 kPa) and still be
considered normal. It may vary with engine speed,
outside temperature and oil viscosity, but readings
above the shaded area show the normal operating
range. Readings in the shaded area tell you that
the engine is low on oil, or that you might have some
other oil problem. SeeEngine Oil on page 5-13. United States
Canada
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•SAE 5W-30
As shown in the viscosity chart, SAE 5W-30 is best
for your vehicle. However, you can use SAE
10W-30 if it is going to be 0°F (-18°C) or above.
These numbers on an oil container show its
viscosity, or thickness. Do not use other viscosity
oils such as SAE 20W-50.
Oils meeting these
requirements should also
have the starburst
symbol on the container.
This symbol indicates
that the oil has been
certified by the American
Petroleum Institute (API).
You should look for this on the oil container, and use
onlythose oils that are identified as meeting GM
Standard GM4718M and have the starburst symbol on
the front of the oil container.
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Park on a fairly steep hill, with the vehicle facing
downhill. Keeping your foot on the regular brake, set the
parking brake.
•To check the parking brake’s holding ability: With
the engine running and transmission in
NEUTRAL (N), slowly remove foot pressure from
the regular brake pedal. Do this until the vehicle is
held by the parking brake only.
•To check the PARK (P) mechanism’s holding ability:
With the engine running, shift to PARK (P). Then
release the parking brake followed by the regular
brake.
Contact your GM Goodwrench dealer if service is
required.
Underbody Flushing Service
At least every spring, use plain water to flush any
corrosive materials from the underbody. Take care to
clean thoroughly any areas where mud and other debris
can collect.
Recommended Fluids and
Lubricants
Fluids and lubricants identified below by name, part
number or specification may be obtained from your
dealer.
Usage Fluid/Lubricant
Engine OilThe engine requires a special
engine oil meeting GM Standard
GM4718M. Oils meeting this
standard may be identified as
synthetic, and should also be
identified with the American
Petroleum Institute Certified for
Gasoline Engines starburst symbol.
However, not all synthetic API oils
with the starburst symbol will meet
this GM standard. You should look
for and use only an oil that meets
GM Standard GM4718M. GM
Goodwrench oil meets all the
requirements for your vehicle. For
the proper viscosity, seeEngine Oil
on page 5-13.
Engine Coolant50/50 mixture of clean, drinkable
water and use only
DEX-COOL
®Coolant. SeeEngine
Coolant on page 5-23.
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