1998 GMC SIERRA oil viscosity

Oil Pressure Gage
0
Y3
80
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.
I
Don’t keep driving if the oil pressure is low. If
you do, your engine can become
so hot that it
catches fire.
You or others could be burned.
Check your oil as soon as possible and have your
vehicle serviced.
I NOTICE:
Damage to your engine from neglected oil problems
can be costly and is not covered by your warranty.
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What Kind of Engine Oil to Use
Oils recommended for your vehicle can be identified by
looking for the “Starburst” symbol. This symbol
indicates that
the oil has been certified by the American
Petroleum Institute (API).
Do not use any oil which
does not carry this Starburst symbol.
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 Petroleutn Institute
certified for gasoline engines.
You should
also use the proper viscosity oil for your
vehicle, as shown in the following chart:
RECOMMENDED SAE VISCOSITY GRADE ENGINE OILS
FOR BEST FUEL ECONOMY AND COLD STARTING, SELECT THE LOWEST
SAL VISCOSITY GRADE OIL
FOR THE EXPECTED TEMPERATURE RANGE.
LOOK
FOR THIS
SYMBOL
COLD
WEATHER
DO NOT USE SAE 2OW-50 OR ANY OTHER GRADE OIL NOT RECOMMENDED
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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.
Engine Oil Additives
Don’t add anything to your oil. Your dealer is ready to
advise if
you think something should be added.
When to Change Engine Oil
If any one of these is true for you, use the short tripkity
maintenance schedule:
Most trips are less than 5 to 10 miles (8 to 16 km).
This is particularly important when outside
temperatures are below freezing.
Most trips include extensive idling (such as frequent
driving
in stop-and-go traffic).
You operate your vehicle in dusty areas or
off-road frequently.
You frequently tow a trailer.
The vehicle is used for delivery service, police, taxi
or other commercial application.
Driving under these conditions causes engine
oil to
break down sooner.
If any one of these is true for your
vehicle,
then you need to change your oil and filter
every
3,000 miles (5 000 km) or 3 months -- whichever
occurs first.
If none of them is true, use the long trip/highway
maintenance schedule. Change the oil and filter every
7,500 miles (12 500 km) or 12 months -- whichever
occurs first. Driving a vehicle with
a fully warmed
engine under highway conditions causes engine
oil to
break down slower.
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Part D: Recommended Fluids
and Lubricants
NOTE: Fluids and lubricants identified below by name,
part number or specification may be obtained from
your dealer.
USAGE
Engine Oil
(Gasoline
Engine)
Engine Coolant
~~
Hydraulic Brake
System
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.
50/50 mixture of clean water
(preferably distilled) and use only
GM Goodwrench@ DEX-COOL@
or Havoline@ DEX-COOL@
Coolant. See “Engine Coolant” in
the Index.
Delco Supreme
11 @ Brake Fluid
(GM Part
No. 12377967 or
equivalent
DOT-3 Brake Fluid).
USAGE
Hydraulic Clutch
System
Parking Brake
Cable Guides
~
Power Steering System
Manual
Transmission (5-Speed with
Low Gear, RPO
MW3)
Manual
Transmission (5-Speed without
Low Gear,
RPO
MG5)
FLUID/LUBRICANT
Hydraulic Clutch Fluid (GM Part
No. 12345347 or equivalent
DOT-3 Brake Fluid).
Chassis Lubricant (GM Part
No. 12377985 or equivalent) or
lubricant meeting requirements
of
NLGI # 2, Category LB or
GC-LB.
GM Power Steering Fluid (GM
Part
No. 1052884 - 1 pint,
1050017
- 1 quart, or equivalent).
GM Goodwrench Synthetic
Manual Transmission Gear Oil
(GM Part No. 12346190
- 1 st.) or
equivalent
SAE 75W-90 GL-4
Gear Oil.
Synchromesh Transmission Fluid (GM Part
No. 12345349 or
equivalent).
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