Page 149 of 436

Have you recently changed brands of fuel?
If so, be sure to fuel your vehicle with quality fuel (see
“Fuel” in the Index). Poor fuel quality will cause your
engine not to run as efficiently as designed. You
may
notice this as stalling after start-up, stalling when you
put the vehicle into gear, misfiring, hesitation on
acceleration
or stumbling on acceleration. (These
conditions may go away once the engine is warmed up.)
This will be detected by the system and cause the light
to turn
on.
If you experience one or more of these conditions,
change the
fuel brand you use. It will require at least
one full tank
of the proper fuel to turn the light off.
If none of the above steps have made the light turn off,
have your dealer
or qualified service center check the
vehicle. Your dealer has the proper test equipment and
diagnostic tools
to fix any mechanical or electrical
problems that may have developed.
Oil Pressure Gage
The oil pressure gage shows
the engine oil pressure in
psi (pounds per square inch)
when the engine is running.
Canadian vehicles indicate
pressure in kPa
(kilopascals).
Oil pressure may vary
with engine speed, outside
temperature and oil viscosity, but readings above
the
low pressure zone indicate the normal operating range.
A reading in the low pressure zone may be caused by
a dangerously low oil level or some other problem
causing low oil pressure. Check your oil as soon
as possible.
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Page 292 of 436

I 1 What Kind of Oil to Use
I NOTICE: I Oils recommended for your vehicle can be identified by
looking
for the “Starbuk” symbol. This symbol
.I
Don’t add too much oil. If your engine has so indicates that the oil has been certified by the American
much oil that the oil level gets above the upper Petroleum Institute (API). Do not use any oil which
mark that shows the proper operating range, does not carry this Starburst symbol.
The engine oil fill cap
for the “VORTEC”
4300,
5000 and 5700 engines are
located on the driver’s side
engine valve cover.
your engine could be damaged.
I
The engine oil fill cap for the “VORTEC” 7400 engine
is located at the front of the engine.
Be sure to fill it enough to put the level somewhere
in
the proper operating range. Push the dipstick all the way
back
in when you’re through. If you
change your own oil,
be sure
you use oil that has
the Starburst symbol on
the
front of the oil container.
If you have your oil changed for you, be sure the oil put
into your engine
is American Petroleum Institute
certified for gasoline engines.
You should also use the proper viscosity oil for your
vehicle, as shown
in the following chart:
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Page 293 of 436

RECOMMENDED SAE YlSCOSlTT GRADE ENGINE OILS I
FOR BEST FUEL ECONOMY AND COLD STARTING, SELECT THE LOWEST
SAL VISCOSITY GRADE OIL
FOR THE EXPECTED TEMPERATURE RANGE. I
HOT
WEATHER
COLD
WEATHER
SAE 5w-30 PREFERRED
LWK
Fm THIS
SYMBOL
DO NOT USE SAE 2ow-50 OR ANY OTHER GRADE OIL NOT RECOMMENDED
As shown in the chart, SAE 5W-30 is best for your
vehicle. However, you can use
SAE 1OW-30 if it’s 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.
NOTICE:
Use only engine oil with the American Petroleum
Institute Certified For Gasoline Engines
“Starburst” symbol. Failure to use the
recommended oil can result in engine damage
not covered by your warranty.
GM Goodwrench@ oil meets all the requirements for
your vehicle.
If you are in an area where the temperature falls below
-20°F (-29”C), consider using either an SAE 5W-30
synthetic oil or an SAE OW-30 oil. Both will provide
easier cold starting and better protection for your engine
at extremely low temperatures.
6-17
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Page 405 of 436

Part D: Recommended Fluids
and Lubricants
NOTE: Fluids and lubricants identified below by name,
part number or specification may be obtained from your
GM dealer.
USAGE
Engine Oil (Gasoline Engine)
’*
Engine Coolant
~
FLUIDLUBRICANT
Engine oil with the American
Petroleum Institute Certified For
Gasoline Engines “Starburst”
symbol of the proper viscosity. To
determine the preferred viscosity
for your vehicle’s engine, see
“Engine Oil” in the Index.
~
50150 mixture of clean water
(preferably distilled) and use only
GM Goodwrench’ DEX-COOL@
or Havoline@ DEX-COOL@
coolant. See “Engine Coolant” in
the Index.
USAGE
Hydraulic Brake
System
~
Hydraulic Clutch
System
Parking Brake
Cable Guides
Power Steering
System
Manual
Transmission
(5-Speed with
Low Gear,
RPO
MW3)
FLUIDLUBRICANT
Delco Supreme 11 ’ Brake Fluid
(GM Part
No. 12377967 or
equivalent DOT-3 brake fluid).
Hydraulic Clutch Fluid (GM Part
No. 12345347 or equivalent
DOT-3 brake fluid).
Chassis lubricant (GM Part
No. 1052497 or equivalent) or
lubricant meeting requirements
of NLGI
# 2, Category LB
or GC-LB.
GM Power Steering Fluid
(GM Part No. 1052884
- 1 pint,
10500 17
- 1 quart, or equivalent).
GM Goodwrench Synthetic
Manual Transmission Gear Oil
Castrol syntorq’
LT or equivalent
SAE 75W-90 GL-4 gear oil.
(GM
Part NO. 12346190 - 1 st.),
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ProCarManuals.com