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Engine Oil
If the CHECK ENG OIL
LEVEL message appears
on the instrument cluster,
it means you need to
check your engine oil
level right away.
For more information, see ªCHECK ENG OIL LEVELº
in the Index.
You should check your engine oil level regularly; this is
an added reminder.
Checking Engine Oil
It's a good idea to check your engine oil every time you
get fuel. In order to get an accurate reading, the oil must
be warm and the vehicle must be on level ground.
8100 Engines All Other Engines
The engine oil dipstick has a yellow ring handle and
is located in 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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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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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.
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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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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.
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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's GVWR is over 8,600 or
if the vehicle is mainly driven under one or more of
these conditions:
In heavy city traffic where the outside temperature
regularly reaches 90F (32C) or higher.
In hilly or mountainous terrain.
When doing frequent trailer towing.
Uses such as found in taxi, police or delivery service.
If your vehicle's GVWR is not over 8,600 and you
do not use your vehicle under any of these
conditions, change the fluid and filter
every 100,000 miles (166 000 km).
See ªScheduled Maintenance Servicesº in the Index.
How to Check
Because this operation can be a little difficult, you
may choose to have this done at the 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.
Too little fluid could cause the transmission to
overheat. Be sure to get an accurate reading if
you check your transmission fluid.
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Then, without shutting off the engine, follow these steps:
The red transmission
dipstick handle with the
TRANS/LOCK text or
graphic is located at the rear
of the engine compartment,
on the passenger's side.
See ªEngine Compartment Overviewº in the Index for
more information on location.1. Flip the handle up and then pull out the dipstick and
wipe it with a clean rag or paper towel.
2. Push it back in all the way, wait three seconds and
then pull it back out again.
3. Check both sides of the dipstick, and read the lower
level. The fluid level must be in the COLD area,
below the cross±hatched 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; then flip the handle
down to lock the dipstick in place.