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6-16
Turn off the engine and give the oil several minutes to
drain back into the oil pan. If you don't, the oil dipstick
might not show the actual level.
Pull out the dipstick and clean it with a paper towel or
cloth, then push it back in all the way. Remove it again,
keeping the tip down, and check the level.When to Add Engine Oil
If the oil is at or below the ADD mark, then you'll need
to add at least one quart of oil. But you must use the
right kind. This part explains what kind of oil to use.
For engine oil crankcase capacity, see ªCapacities and
Specificationsº in the Index.
NOTICE:
Don't add too much oil. If your engine has so
much oil that the oil level gets above the
cross
-hatched area that shows the proper
operating range, your engine could be damaged.
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6-17
8100 Engines All Other Engines
The engine oil fill cap
for the VORTEC 4800,
5300, 6000 and 8100 V8
engines is located on the
engine valve cover, on
the passenger's side of
the vehicle.
Your vehicle may have a cap with text and a graphic,
or just a graphic as shown. See ªEngine Compartment
Overviewº in the Index for more information
on location.
Be sure to fill it enough to put the level somewhere in
the proper operating range. Push the dipstick all the way
back in when you're through.
Page 339 of 443
6-18 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
gasoline engines.
You should also use the proper viscosity oil for your
vehicle, as shown in the following chart:
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6-19
As in the chart shown previously, SAE 5W-30 is best for
your vehicle. However, you can use SAE 10W
-30 if it's
going to be 0F (
-18C) 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.
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
(GM Oil Life System)
Your vehicle has a computer system that lets you know
when to change the engine oil and filter. This is based on
engine revolutions and engine temperature, and not on
mileage. Based on driving conditions, the mileage at
which an oil change will be indicated can vary
considerably. For the oil life system to work properly,
you must reset the system every time the oil is changed.
When the system has calculated that oil life has been
diminished, it will indicate that an oil change is
necessary. A CHANGE ENGINE OIL message will
come on. Change your oil as soon as possible within the
next two times you stop for fuel. It is possible that, if
you are driving under the best conditions, the oil life
system may not indicate that an oil change is necessary
for over a year. However, your engine oil and filter must
be changed at least once a year and at this time the
system must be reset. It is also important to check your
oil regularly and keep it at the proper level.
If the system is ever reset accidentally, you must change
your oil at 3,000 miles (5 000 km) since your last oil
change. Remember to reset the oil life system whenever
the oil is changed.
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6-20
How to Reset the CHANGE ENGINE OIL Message
The GM Oil Life System calculates when to
change your engine oil and filter based on vehicle use.
Anytime your oil is changed, reset the system so it can
calculate when the next oil change is required. If a
situation occurs where you change your oil prior to a
CHANGE ENGINE OIL message being turned on,
reset the system.
To reset the CHANGE ENGINE OIL message do
the following:
1. Turn the ignition key to RUN with the engine off.
2. Fully press and release the accelerator pedal
three times within five seconds.
If the CHANGE ENGINE OIL message flashes for
five seconds, the system is reset.What to Do with Used Oil
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 threat to the environment. If you
change your own oil, be sure to drain all the oil from the
filter before disposal. Never 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.
Page 342 of 443
6-21
Engine Air Cleaner/Filter
The engine air cleaner/filter assembly has an indicator
that lets you know when the air filter is dirty and needs
to be serviced. The indicator is located on the air cleaner
cover. See ªEngine Compartment Overviewº in the
Index for more information on location.
See ªOwner Checks and Servicesº in the Index to
determine when to check the indicator.
The service window A with
the percentage scale shows
the amount of engine air
cleaner/filter life used.
When both service
window A and service
window B turn orange,
replace the engine
air cleaner/filter.
After changing the air filter, press the top button on the
indicator to reset it.
Your engine air cleaner/filter is located in the front
corner of the engine compartment on the passenger's
side of the vehicle. See ªEngine Compartment
Overviewº in the Index for more information
on location.
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6-22
1. To remove the engine/air cleaner filter, loosen the
screws on the housing cover.
2. Then lift the cover upward and remove the filter
from the housing. Care should be taken to dislodge
as little dirt as possible.
3. Clean the filter sealing surface and the filter housing.
4. Install the new filter.
5. Reinstall the housing cover.Refer to the Maintenance Schedule to determine when to
replace the air filter. See ªOwner Checks and Servicesº
in the Index.
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.
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6-23
Passenger Compartment Air Filter
(If Equipped)
Your vehicle may be equipped with a passenger
compartment air filter. The filter is located under the
instrument panel, below the glove compartment.
Your vehicle may or may not be equipped with an
access panel.
To replace the passenger compartment air filter, do
the following:
1. If your vehicle has an access panel, remove the bolts
on it and set the panel aside. If your vehicle does not
have the access panel, skip this step.
2. Next, pull
downward on the filter
retaining bracket.3. Remove the air filter by pulling downward on the
element. Remove the second portion of the air filter
by sliding it towards the rear of the vehicle and then
pulling downward.
4. Install the new filter by reversing the steps listed
previously. Be sure to follow any instructions that
may be included in the replacement filter package.
Because this procedure can be a little difficult,
you may choose to have it done at your dealer's
service department.
Refer to the Maintenance Schedule to determine when to
replace the passenger compartment air filter. See
ªScheduled Maintenanceº in the Index.