1998 GMC ENVOY oil viscosity

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 gar, 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.
Engine 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 other problems causing low
oil pressure.
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What Kind of Eng 3il 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 Petroleum
Institute certified
for
gasoline engines.
You should also use the proper viscosity oil for your
vehicle, as shown in the following chart:
I RECOMMENDED SA€ VISCOSITY GRADE ENGINE OILS
FOR BEST FUEL ECONOMY AND COLD STARTING, SELECT THE LOWEST
I SAL VISCOSITY GRADE OIL FOR THE EXPECTED TEMPERATURE RANGE.
L
HOT
WEATHER
+ 20 7
SAE SW-30 PREFERRED
LOOK
FOR MIS
SYMBOL
00 NOT USE SAE 2OW-50 OR ANY OTHER
GRADE OIL NOT RECOMMENDED
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As shown in the chart, SAE SW-30 is best for your
vehicle. However, you can use
SAE low-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-SO.
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:
0 Most trips are less than 5 to 10 miles (8 to 16 km).
This is particularly important when outside
temperatures are below freezing.
driving
in stop-and-go traffic).
off-road frequently. your vehicle.
or other commercial application.
0 Most trips include extensive idling (such as frequent
0 You operate your vehicle in dusty areas or
0 You frequently tow a trailer or use a carrier on top of
0 The vehicle is used for delivery service, police, taxi
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
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
1 1 @ Brake Fluid
(GM Part No. 12377967 or
equivalent DOT-3 Brake Fluid).
USAGE
Parking Brake
Cable Guides
Power Steering System
Automatic
Transmission
Key Lock
Cylinders
Chassis
Lubrication
Differential,
Front and Rear
Axle
FLUIDLUBRICANT
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,
10500 17 - 1 quart, or equivalent).
DEXRON@-I11 Automatic
Transmission Fluid.
Multi-Pu
ose Lubricant,
Superlube
% (GM Part
No. 1234624 1 or equivalent).
Chassis Lubricant
(GM Part
No. 12377985 or equivalent) or
lubricant meeting requirements
of
NLGI # 2, Category LB or
GC-LB.
Axle Lubricant (GM Part
No. 1052271) or SAE 8OW-90
GL-5 Gear Lubricant.
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