
Service
Your Geo dealer knows your vehicle best and wants you
to be happy with it. We hope you’ll go to your dealer for
all your service needs. You’ll get genuine
GM parts and
GM-trained and supported service people.
We hope you’ll want to keep your GM vehicle all
GM.
Genuine GM parts have one of these marks:
Delco
Doing Your Own Service Work
If you want to do some of your own service work, you’ll
want to use the proper Geo Service Manual. It tells you
much more about how to service your Geo than this
manual can.
To order the proper service manual, see
“Service and Owner Publications” in the Index.
Your vehicle has an air
bag system. Before attempting to
do your own service work,
see “Servicing Your Air
Bag-Equipped Geo” in the Index.
You should keep a record with all parts receipts and list
the mileage and the date
of any service work you
perform. See “Maintenance Record” in the Index.
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I
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.
0
0 Be sure you have sufficient knowledge,
experience, the proper replacement parts
and tools before you attempt any vehicle
maintenance task.
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.
Adding Equipment to the Outside of
Your Vehicle
Things you might add to the outside of your vehicle can
affect the airflow around it. This may cause wind noise
and affect windshield washer performance. Check with
your Geo dealer before adding equipment to the outside
of your vehicle.
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 Canada. Improved gasoline specifications have been
developed by
the American Automobile Manufacturers
Association (AAMA) for better vehicle performance
and engine protection. Gasolines meeting 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.
Some gasolines that are not reformulated for low
emissions contain an octane-enhancing additive called
methylcyclopentadienyl manganese tricarbonyl (MMT);
ask your service station operator whether or not his
fuel
contains MMT. General Motors does not recommend the
use of such gasolines.
If fuels containing MMT are used,
spark plug life may be reduced and your emission
control system performance may be affected. The
malfunction indicator lamp on your instrument panel
may
turn on. If this occurs, return to your authorized
Geo dealer for service. To
provide cleaner air, all gasolines in the United States
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.
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 1OW-30 is best for your
vehicle. However, you can use
SAE 5W-30 if it’s going
to be colder than
60°F ( 16°C) before your next oil
change. When it’s very cold, you should use
SAE 5W-30. 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 Geo 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:
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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, use the long triphighway
maintenance schedule. Change oil and filter every
7,500 miles (12 500 km) or 7.5 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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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. Wdsh 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
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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:
3. Pull out the filter.
0 In heavy city traffic where the outside temperature
regularly reaches
90°F (32°C) or higher.
0 In hilly or mountainous terrain.
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.
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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
on the dipstick.
I 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 (IOOC), 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.
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3. Check both sides of the dipstick, and read the lower
level. The fluid level must be
in the COLD area for a
cold check or
in the HOT area or cross-hatched area
for a hot check.
4. If the fluid level is in the acceptable range, push the
dipstick back in all the way.
How to Add Fluid
Refer to the Maintenance Schedule to determine what
kind
of transmission fluid to use. See “Recommended
Fluids and Lubricants” in the Index. Add
fluid only after checking the transmission fluid
HOT. (A COLD check
is used only as a reference.) If
the fluid level is low, add only enough of the proper
fluid to bring the level up to the HOT area for a hot
check.
It doesn’t take much fluid, generally less than
one pint
(0.5 L). Don ’I ove$iZZ.
NOTICE:
We recommend you use only fluid labeled
DEXRON@-111, because fluid with that label is
made especially for your automatic transmission.
Damage caused by fluid other than DEXRON-I11
is not covered by your new vehicle warranty.
0 After adding fluid, recheck the fluid level as
0 When the correct fluid level is obtained, push the
described under
“How to Check.”
dipstick back
in all the way.
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.
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