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A CAUTION:
~ ~~
You can be injured and your vehicle could be
damaged if you try to
do service work on a
vehicle without knowing enough about it.
Be sure you have sufficient knowledge,
experience, and the proper replacement
parts and tools before you attempt any
vehicle maintenance task.
0 Be sure to use the proper nuts, bolts and
other fasteners. “English,’ and “metric”
fasteners can be easily confused.
If you use
the wrong fasteners, parts can later break
or fall off. You could be hurt.
Fuel
Use regular unleaded gasoline rated at 87 octane or higher.
At a
minimum, it should meet specifications ASTM D4814
in the United States and CGSB 3.5-M93 in cana$a
Improved gasoline specifications have been developed by
the American Automobile Manufacturers Association
(AAMA) for better vehicle performance and engine
protection.
Gasolines meting the AAMA specification
could provide improved driveability
and emission control
system protection compared to other gasolines.
Be sure the posted octane is at least 87. If the octane is
less than 87, you may get a heavy knocking noise when
you drive. If
it’s bad enough, it can damage your engine.
If you’re using fuel rated at 87 octane or higher and you
still hear heavy knocking, your engine needs service.
But don’t worry
if you hear a little’pinging noise when
you’re accelerating or driving up a hill. That’s normal,
and you don’t have to buy
a higher octane fuel to get rid
of pinging. It’s the heavy, constant knock that means
you have a problem.
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If your vehicle is certified to meet California Emission
Standards (indicated
on the underhood tune-up label), it
is designed to operate on fuels that meet California
specifications. If such fuels are not available in states
adopting California emissions standards, your vehicle
will operate satisfactorily on fuels meeting federal
specifications, but emission control system performance
may be affected. The malfunction indicator lamp on
your instrument panel may turn on and/or your vehicle
may fail a smog-check test. If this occurs, return to your
authorized Geo dealer for diagnosis to determine the
cause
of failure. In the event it is determined that the
cause
of the condition is the type of fuels used, repairs
may not be covered by your warranty.
In Canada, some gasolines contain an octane-enhancing
additive called
MMT. If you use such fuels, your
emission control system performance may deteriorate
and the malfunction indicator lamp
on your instrument
panel may turn
on. If this happens, return to your
authorized Chevrolet/Geo dealer for service.
To provide cleaner air, all gasolines are now required to
contain additives that will help prevent deposits
from
forming in your engine and fuel system, allowing your
emission control system
to function properly. Therefore,
you should not have to add anything to the fuel.
In
addition, gasolines containing oxygenates, such as ethers
and ethanol, and reformulated gasolines may be available
in your area to help clean the air. General Motors
recommends that you use these gasolines
if they comply
with the specifications described earlier.
1 NOTICE:
,
Your vehicle was not designed for fuel that
contains methanol. Don’t use it. It can corrode
metal parts in your fuel system and also damage
plastic and rubber parts. That damage wouldn’t
be covered under your warranty.
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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 (-1 8 “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.
Engine Oil Additives
Don’t add anything to your oil. Your Geo dealer is ready
to advise if
you think something should‘be added.
When to Change Engine Oil
See if any one of these is true for you:
0
e
e
0
e
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 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.
If none of them is true, change oil and filter every
7,500 miles (12 500 km) or 7.5 months -- whichever
occurs first.
Driving a vehicle with a fully warned
engine under highway conditions causes engine oil to
break down slower.
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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 dealer, a service station or a local recycling
center for help.
Air Cleaner
Refer to the Maintenance Schedule to determine when to
replace the air filter and the crankcase ventilation filter.
See “Scheduled Maintenance Services” in the Index.
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3. Pull out the filter.
Automatic Transmission Fluid
When to Check and Change
A good time to check your automatic transmission 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.
When doing frequent trailer towing.
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.
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How to Check
Because this operation can be a little difficult, you
may choose to have t,his done at
your Geo dealership
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
transmission. 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
transmission fluid.
Wait at least 30 minutes before checking the
transmission 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).
Checking Transmission Fluid Hot
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), drive the
vehicle
in DRIVE (D) until the engine temperature gage
moves and then remains steady for
10 minutes. Then
follow the hot check procedures.
Checking Transmission Fluid Cold
A cold check is made after the vehicle has been sitting
for eight hours or more with the engine off and is used
only
as a reference. Let the engine run at idle for five
minutes
if outside temperatures are 50 "F (10" C) or
more.
If it's colder than 50°F (lO°C), you may have to
idle the engine longer. Should the fluid level be low
during
a cold check, you must perform a hot check
before adding fluid. This will give
vou a more accurate
reading of the fluid level.
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Manual Transmission Fluid
When to Check and Change
A good time to have it checked is when the engine
oil is changed. Refer to the Maintenance Schedule to
determine when to change your transmission fluid.
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 Geo dealership
Service Department.
If you do it yourself, be sure to follow all the
instructions
here, or you could get a false reading.
NOTICE:
Too much or too little fluid can damage your
transmission.
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
transmission fluid.
Check the fluid level only when your engine is off, the
vehicle is parked on a level place and the transmission is
cool enough for
you to rest your fingers on the
transmission case.
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Clutch Adjustment
The clutch linkage in your vehicle should be checked as
recommended
in your Maintenance Schedule. To check,
push the clutch pedal down with your hand until you
feel some resistance to movement of the pedal. If the
pedal moves freely up to
1 inch (25 mm) or so before
you feel resistance
to the travel, adjustment isn’t needed.
If there is no free travel or very. little (less than 5/8 of an
inch
(1 6 mm)), see your dealer for adjustment.
Rear Axle
When to Check and Change Lubricant
Refer to the Maintenance Schedule to determine how
often to check the lubricant and when to change it. See
“Periodic Maintenance Inspections” and “Scheduled
Maintenance Services” in the Index.
How to Check Lubricant
If the level is below the bottom of the filler plug hole,
you’ll need to add
some lubricant. Add enough lubricant
to raise the level
to the bottom of the filler plug hole.
What to Use
Refer to the Maintenance Schedule to determine what
kind of lubricant to use. See “Recommended Fluids and
Lubricants” in the Index.
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