1998 OLDSMOBILE SILHOUETTE engine

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 Petroleum
Institute certified for
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
SAE VISCOSITY GRADE OIL
FOR THE EXPECTED TEMPERATURE RANGE.
HOT
WEATHER
’ “F /’
+ 40
+ 20
WOK
FOR THIS
SYMBOL
SAL 1OW-30
1-30 RED
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 IOW-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 2OW-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 retailer 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 triplcity
maintenance schedule:
0
0
0
0
0
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).
Most trips are through dusty areas.
YOU frequently tow a trailer or use a carrier on top of
your vehicle.
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.
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If none of them is true, use the long triphighway
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.
What to Do with Used Oil
Did you know that used engine oil contains certain
elements that may be unhealthy for your skin and could
even cause cancer? Don’t 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 throw
away 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 real threat to the environment. If you
change your own oil, be sure to drain all free-flowing oil
from the filter before disposal. Don’t ever 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 your used oil,
ask your retailer, a service station or a local recycling
center for help.
Air Cleaner
The air cleaner is located at the front of the engine
compartment (on the driver’s side of the vehicle), under
the engine coolant reservoir.
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Checking or Replacing the Air Cleaner
1. Unlatch the two hooks on top of the air
cleaner housing.
2. Turn back the air inlet panel and rest it on top of the
housing. The air intake tube is designed to flex back;
you do not need to disconnect it.
3. After replacing the air cleaner filter, seat the tabs on
the bottom of the panel into the slots at the bottom.
4. Latch the hooks to secure the panel in place. If the
panel moves easily, check that the tabs
are seated
correctly in the slots.
NOTICE:
If the air cleaner is off, a backfire can cause a
damaging engine fire. And, dirt can easily get
into your engine, which will damage it. Always
have the air cleaner in place when you’re driving.
Passenger Cornparti .t Air
Filter Replacemem
Passenger compartment air, both outside and
I recirculated air, is routed through a passenger
compartment filter, which is part of
a two-piece filter
system. The filter removes certain contaminants from
the air, including pollen and dust particles. Reductions
Operating the engine with the air cleaner off can in airflow, which may occur more quickly in dusty
cause you or others to be burned. The air cleaner areas, indicate that the filter needs to be replaced early.
not only cleans the air, it stops flame if the engine For how often to change the passenger compartment air
backfires. If it isn’t there, and the engine
backfires, you could be burned. Don’t drive with
The access panel for the passenger compartment air
it off, and be careful working on the engine with filter is in the back of the glove box.
the air cleaner off.
filter, see “Maintenance Schedule” in the Index.
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5. Close the inner access door, while squeezing the tab,
6. Snap the outer access panel into the back of the
to be sure it is
tightly closed.
glove box.
Automatic Transaxle Fluid
r--- In to Check and Change
A good time to check your automatic transaxle fluid
level is when the engine oil is changed.
Change both
the fluid and filter every 50,000 miles
(83 000 km) if the vehicle is mainly driven under one
or more of these conditions:
0 In heavy city traffic where the outside temperature
regularly reaches
90°F (32°C) or higher.
In hilly or mountainous terrain.
0 When doing frequent trailer towing.
0 Uses such as found in taxi, police or delivery service.
If you do not use your vehicle under any
of these
conditions, the fluid and filter do not require changing.
See “Scheduled Maintenance Services” in the Index.
How to Check
Because this operation can be a little difficult, you may
choose to have this done at your Oldsmobile retail
facility Service Department.
If you do it yourself, be sure to follow all the
instructions here, or
you could get a false reading
on the dipstick.
NOTICE:
Too much or too little fluid can damage your
transaxle.
Too much can mean that some of the
fluid could come out and fall on hot engine parts
or exhaust system parts, starting a fire. Be sure to
get an accurate reading if you check your
transaxle fluid.
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Wait at least 30 minutes before checking the transaxle
fluid level if
you have been driving:
When outside temperatures are above 90°F (32°C).
At high speed for quite a while.
In heavy traffic -- especially in hot weather.
While pulling a trailer.
To get the right reading, the fluid should be at normal
operating temperature, which is
180°F to 200°F
(82°C to 93°C).
Get the vehicle warmed up by driving about 15 miles
(24 km) when outside temperatures are above
50°F (10°C). If it's colder than 50°F (lO°C), you
may have to drive longer.
Checking the Fluid Level
Park your vehicle on a level place. Keep the
engine running.
With the parking brake applied, place the shift lever
in PARK (P).
With your foot on the brake pedal, move the shift
lever through each gear range, pausing for about
three seconds in each range. Then, position the shift
lever in
PARK (P).
Let the engine run at idle for three to five minutes.
Then, without shutting off the engine, follow
these steps:
1. The dipstick is located toward the back
of the engine
compartment, next to the brake master cylinder. The
dipstick handle has
a bright red loop design for easy
identification. Pull
out the dipstick and wipe it with a
clean rag or paper towel.
2. Push it back in all the way, wait three seconds and
then pull
it back out again.
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Engine Coolant
The cooling s stem in your vehicle is filled with
DEX-COOL engine coolant. This coolant is designed
to remain in your vehicle for
5 years or 150,000 miles
(240 000 lunb whichever occurs first, if you add only
DEX-COOL extended life coolant.
J
The following explains your cooling system and how
to add coolant when it is low. If you have a problem
with engine overheating, see “Engine Overheating” in
the Index.
A 50/50 mixture of water and DEX-COOL@
coolant will:
Give freezing protection down to -34°F (-37°C).
0 Give boiling protection up to 265 OF (1 29 O C).
Protect against rust and corrosion.
Help keep the proper engine temperature.
Let the warning lights and gages work as
they should.
NOTICE:
When adding coolant, it is important that you
use only
DEX-COOL@ (silicate-free) coolant.
If coolant other than DEX-COOL is added to
the system, premature engine, heater core or
radiator corrosion may result. In addition, the
engine coolant will require change sooner
-- at
30,000 miles (50 000 km) or 24 months,
whichever occurs
first. Damage caused by the
use of coolant other than DEX-COOL@ is not
covered by your new vehicle warranty.
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What to Use
Use a mixture of one-half clean water (preferably
distilled) and one-half
DEX-COOL@ coolant which
won’t damage aluminum parts. If you use this mixture,
you don’t need to add anything else.
Adding only plain water to your cooling system
can be dangerous. Plain water, or some other
liquid like alcohol, can boil before the proper coolant mixture will. Your vehicle’s coolant
warning system is set for the proper coolant
mixture. With plain water or the wrong mixture,
your engine could get too hot but you wouldn’t
get the overheat warning. Your engine could
catch fire and you or others could be burned.
Use
a 50/50 mixture of clean water and
DEX-COOL@ coolant.
J
NOTICE:
If you use an improper coolant mixture, your
engine could overheat and be badly damaged.
The repair cost wouldn’t be covered by your
warranty. Too much water in the mixture can
freeze and crack the engine, radiator, heater core
and other parts.
If you have to add coolant more than four times a year,
have your retailer check your cooling system.
NOTICE:
If you use the proper coolant, you don’t have to
add extra inhibitors or additives which claim to
improve the system. These can be harmful.
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