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6-14
As shown in the chart, SAE 10W-30 is best for your
vehicle. However, you can use SAE 5W
-30 if it's going
to be colder than 60F (16C) 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
-20F (-29C), consider using either an SAE 5W-30
synthetic oil or an SAE 0W
-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. The recommended oils
with the starburst symbol are all you will need for good
performance and engine protection.
When to Change Engine Oil
If any one of these is true for you, use the short trip/city
maintenance schedule:
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 Catera.
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 5,000 miles (8 000 km) or 3 months
-- whichever
occurs first.
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6-15
If none of them is true, use the long trip/highway
maintenance schedule. Change the oil and filter at the first
5,000 miles (8 000 km) or 3 months
-- whichever occurs
first. Then, change the oil and filter every 10,000 miles
(16 000 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 dealer, a service station or a local recycling
center for help.
Engine Air Cleaner/Filter
The air cleaner is located behind the headlamps on
the passenger's side of the engine. Be sure the engine
has cooled before following these steps to replace the
air filter.
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6-17
To reinstall the air cleaner assembly, place the air filter in
the air cleaner lid, then insert the lid and filter together
into the housing. Reattach the five clips, reinstall the air
intake tube and tighten the clamp. Return the coolant
surge tank hose to its proper position.
Refer to the Maintenance Schedule to determine when to
replace the air filter.
See ªScheduled Maintenance Servicesº in the
Maintenance Schedule booklet.
CAUTION:
Operating the engine with the air cleaner/filter
off can cause you or others to be burned. The
air cleaner not only cleans the air, it stops flame
if the engine backfires. If it isn't there, and the
engine backfires, you could be burned. Don't
drive with it off, and be careful working on the
engine with the air cleaner/filter off.
NOTICE:
If the air cleaner/filter 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/filter in place when
you're driving.
Passenger Compartment Air
Filter Replacement
The passenger compartment air filter traps most
of the pollen from the air entering your vehicle.
Like your vehicle's air cleaner filter, it may need to
be changed periodically. For how often to change the
passenger compartment air filter, see your Maintenance
Schedule booklet.
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6-18
The access panel for the passenger compartment air
filter is below the grille, at the base of the windshield on
the passenger's side of the engine compartment.
1. Open the hood of your vehicle.
2. Lift the engine compartment rear seal (see the arrow
in the illustration) and pull it back far enough to be
able to lift open the grille flap.
3. Unhook both retaining clips that secure the filter
in place.
4. Slide the filter toward the front of the car and then
pull the filter straight out.5. Replace the filter by sliding a new one in,
reattaching both retaining clips and closing the
grille flap.
6. Reinstall the engine compartment rear seal.
7. Close the engine hood.
For the type of filter to use, see ªNormal Maintenance
Replacement Partsº in the Index.
Page 264 of 321

6-20 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 ªRecommended Fluids
and Lubricantsº in the Maintenance Schedule booklet.
Engine Coolant
The cooling system 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 km), whichever occurs first,
if you add only DEX
-COOL extended life coolant.
The following explains your cooling system and how
to add coolant when it is low. If you have a problem
with engine overheating, see ªEngine Overheatingº
in the Index.
A 50/50 mixture of clean, drinkable water and
DEX
-COOL coolant will:
Give freezing protection down to
-34F (-37C).
Give boiling protection up to 265F (129C).
Protect against rust and corrosion.
Help keep the proper engine temperature.
Let the warning lights and gages work as
they should.
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6-21
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.
What to Use
Use a mixture of one-half clean, drinkable water and
one
-half DEX-COOL coolant which won't damage
aluminum parts. If you use this coolant mixture, you
don't need to add anything else.
CAUTION:
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, drinkable water
and DEX
-COOL coolant.
Page 266 of 321
6-22
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 dealer 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.
Checking Coolant
The surge tank is located behind the air cleaner on the
passenger's side of the engine.
The cooling system when hot is under a lot of pressure.
If the low coolant warning light on the instrument panel
appears, you will need to add coolant.
Page 267 of 321
6-23
CAUTION:
Turning the surge tank pressure cap when the
engine and radiator are hot can allow steam and
scalding liquids to blow out and burn you badly.
Never turn the surge tank pressure cap
-- even a
little
-- when the engine and radiator are hot.
The vehicle must be on a level surface. When your
engine is cold, the coolant level should be at the
KALT/COLD line (seam).
If the light comes on and
stays on, it means you're
low on engine coolant.
For more information, see ªLow Coolant Warning
Lightº in the Index.Adding Coolant
If you need more coolant, add the proper DEX
-COOL
coolant mixture at the surge tank, but only when the
engine is cool.
CAUTION:
You can be burned if you spill coolant on hot
engine parts. Coolant contains ethylene glycol,
and it will burn if the engine parts are hot
enough. Don't spill coolant on a hot engine.
When replacing the pressure cap, make sure it is hand-tight.