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:
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).
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 Use
Use a mixture of one-half clean water (preferably
distilled) and one-half coolant that meets
GM
Specification 1825-M, which won’t damage aluminum
parts. You can also use a recycled coolant conforming to
GM Specification 1825-M with a complete coolant flush
and refill. 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 mix will. Your vehicle’s coolant warning
system is set for the proper coolant mix. With
plain water or the wrong mix, 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 mix of clean
water and the proper coolant.
I
NOTICE:
If you use an improper coolant mix, your engine
could overheat and be badly damaged. The
repair cost wouldn’t be covered by your
warranty.
Too much water in the mix 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 dealer check your cooling system.
I 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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