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What Kind of Engine Oil to Use
Look for three things:
•GM6094M
Your vehicle’s engine requires oil meeting
GM Standard GM6094M. Look for and use
only an oil that meets GM Standard GM6094M.
•SAE 5W-30
As shown in the viscosity chart, SAE 5W-30
is best for your vehicle.These numbers on an oil container show its
viscosity, or thickness. Do not use other
viscosity oils such as SAE 20W-50.
•Oils meeting these
requirements should
have the starburst
symbol on the
container. This
symbol indicates
that the oil has been
certified by the
American Petroleum
Institute (API).
Look for this information on the oil container, and
use only those oils that are identified as meeting
GM Standard GM6094M and have the starburst
symbol on the front of the oil container.
Notice:Use only engine oil identi ed as
meeting GM Standard GM6094M and showing
the American Petroleum Institute Certi ed
For Gasoline Engines starburst symbol. Failure
to use the recommended oil can result in
engine damage not covered by your warranty.
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If you are in an area of extreme cold, where the
temperature falls below−20°F (−29°C), it is
recommended that you use either an SAE 5W-30
synthetic oil or an SAE 0W-30 oil. Both provide
easier cold starting and better protection for
the engine at extremely low temperatures.
Engine Oil Additives
Do not add anything to the oil. The recommended
oils with the starburst symbol that meet GM
Standard GM6094M are all you need for good
performance and engine protection.
Engine Oil Life System
(Gasoline Engine)
When to Change Engine Oil
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 light will come on.
SeeChange Engine Oil Light on page 183. Change
the oil as soon as possible within the next 600 miles
(1 000 km). It is possible that, if you are driving
under the best conditions, the oil life system might
not indicate that an oil change is necessary for over
a year. However, the engine oil and filter must be
changed at least once a year and at this time the
system must be reset. Your dealer/retailer has
trained service people who will perform this work
using genuine parts and reset the system. It is also
important to check the oil regularly and keep it at
the proper level.
If the system is ever reset accidentally, you must
change the 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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How to Reset the Engine Oil
Life System
The Engine Oil Life System calculates when to
change the engine oil and filter based on vehicle
use. Anytime the oil is changed, reset the
system so it can calculate when the next oil
change is required. If a situation occurs where you
change the oil prior to a change engine oil light
being turned on, reset the system.
To reset the change engine oil light:
1. Turn the ignition key to RUN with the
engine off.
2. Fully press and release the accelerator pedal
slowly three times within five seconds.
3. If the Change Engine Oil light flashes for
five seconds, the system is reset.
4. Turn the key to LOCK.
If the change engine oil light comes back on when
you start your vehicle, the engine oil life system
has not reset. Repeat the procedure. If it still does
not reset, see your dealer/retailer for service.
SeeChange Engine Oil Light on page 183.
What to Do with Used Oil
Used engine oil contains certain elements that can
be unhealthy for your skin and could even cause
cancer. Do not 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
dispose of 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 used oil, ask
your dealer/retailer, a service station, or a local
recycling center for help.
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Engine Air Cleaner/Filter
If your vehicle has the DURAMAX®Diesel engine,
see the DURAMAX®Diesel manual for more
information.
The engine air cleaner/filter is located near the
center of the engine compartment. SeeEngine
Compartment Overview on page 302for more
information on location.
When to Inspect the Engine
Air Cleaner/Filter
Inspect the air cleaner/filter at the MaintenanceII
intervals and replace it at the first oil change
after each 50,000 mile (85 000 km) interval.
SeeScheduled Maintenance (Gasoline Engine)
on page 405for more information. If you are
driving in dusty/dirty conditions, inspect the filter
at each engine oil change.
How to Inspect the Engine
Air Cleaner/Filter
To inspect the air cleaner/filter, remove the filter
from the vehicle and lightly shake the filter to
release loose dust and dirt. If the filter remains
caked with dirt, a new filter is required. Never use
compressed air to clean the filter.
To inspect or replace the engine air cleaner/filter,
do the following:
1. Unhook the retainer clips and remove
the cover.
2. Lift the filter out of the engine air cleaner/filter
housing. Care should be taken to dislodge as
little dirt as possible.
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3. Clean the engine air cleaner/filter housing.
4. Inspect or replace the engine air cleaner/filter.
Make sure that the filter fits properly into the
housing.
5. Reinstall the cover and fasten the
retaining clips.
{CAUTION:
Operating the engine with the air cleaner/
lter off can cause you or others to be
burned. The air cleaner not only cleans the
air; it helps to stop ames if the engine
back res. If it is not there and the engine
back res, you could be burned. Do not
drive with it off, and be careful working on
the engine with the air cleaner/ lter off.
Notice:If the air cleaner/ lter is off, a back re
can cause a damaging engine re. And, dirt
can easily get into your engine, which will
damage it. Always have the air cleaner/ lter
in place when you are driving.
Automatic Transmission Fluid
If your vehicle has the DURAMAX®Diesel engine,
see the DURAMAX®Diesel manual for more
information.
When to Check and Change
Automatic Transmission Fluid
A good time to check your automatic transmission
fluid level is when the engine oil is changed.
Change the fluid and filter at the intervals listed in
Additional Required Services (Gasoline Engine)
on page 408, and be sure to use the transmission
fluid listed inRecommended Fluids and
Lubricants on page 415.
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How to Check Automatic
Transmission Fluid
Because this operation can be a little difficult, you
may choose to have this done at the dealer/retailer
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 uid can
damage your transmission. Too much can
mean that some of the uid could come out
and fall on hot engine parts or exhaust system
parts, starting a re. Too little uid could
cause the transmission to overheat. Be sure
to get an accurate reading if you check
your transmission uid.
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).
Get the vehicle warmed up by driving about
15 miles (24 km) when outside temperatures are
above 50°F (10°C). If it is colder than 50°F (10°C),
drive the vehicle in DRIVE (D) until the engine
temperature gage moves and then remains
steady for 10 minutes.
A cold fluid check can be made after the vehicle
has been sitting for eight hours or more with
the engine off, but this is used only as a reference.
Let the engine run at idle for five minutes if
outside temperatures are 50°F (10°C) or more.
If it is colder than 50°F (10°C), you may have
to idle the engine longer. Should the fluid level be
low during this cold check, you must check the
fluid hot before adding fluid. Checking the fluid
hot will give you a more accurate reading of
the fluid level.
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Checking the Fluid Level
Prepare your vehicle as follows:
1. Park your vehicle on a level place. Keep the
engine running.
2. With the parking brake applied, place the shift
lever in PARK (P).
3. With your foot on the brake pedal, move the
shift lever through each gear range, pausing
for about three seconds in each range.
Then, position the shift lever in PARK (P).
4. Let the engine run at idle for three minutes
or more.
Then, without shutting off the engine, follow
these steps:
The transmission
dipstick is located near
the center of the
engine compartment
and will be labeled with
the graphic shown.SeeEngine Compartment Overview on page 302
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 for a cold check or in the HOT
or cross-hatched area for a hot check. Be sure
to keep the dipstick pointed down to get an
accurate reading.
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.
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How to Add Automatic
Transmission Fluid
Refer to the Maintenance Schedule to determine
what kind of transmission fluid to use. See
Recommended Fluids and Lubricants on page 415.
Using a funnel, add fluid down the transmission
dipstick tube only after checking the transmission
fluid while it is 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 does not take
much fluid, generally less than one pint (0.5 L).
Do not overfill.
Notice:Use of the incorrect automatic
transmission uid may damage your vehicle,
and the damages may not be covered by
your warranty. Always use the automatic
transmission uid listed inRecommended
Fluids and Lubricants on page 415.
•After adding fluid, recheck the fluid level as
described under “How to Check Automatic
Transmission Fluid,” earlier in this section.
•When the correct fluid level is obtained, push
the dipstick back in all the way; then flip the
handle down to lock the dipstick in place.
Engine Coolant
If your vehicle has the DURAMAX®Diesel engine,
see the DURAMAX®Diesel manual for more
information.
The cooling system in your vehicle is filled with
DEX-COOL
®engine coolant. This coolant is
designed to remain in your vehicle for five 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, seeEngine
Overheating on page 315.
A 50/50 mixture of clean, drinkable water and
DEX-COOL
®coolant will:
•Give freezing protection down to−34°F (−37°C).
•Give boiling protection up to 265°F (129°C).
•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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