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What Kind of Engine Oil to Use
Look for these two things:
•CI-4 or CH-4
Oils designated as API CI-4 or CH-4 are
recommended for your vehicle. The CI-4 or CH-4
designations may appear either alone, together, or
in combination with other API designations, such
as API CI-4/SL.
These letters show American Petroleum Institute
(API) levels of quality.
Notice:Use only engine oils that have one of these
designations CI-4 or CH-4 for the DURAMAX
®
diesel engine. Failure to use the recommended oils
can result in engine damage not covered by your
warranty.
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•SAE 15W-40
As shown in the viscosity chart, SAE 15W-40 is
best for your vehicle. However, you can use
SAE 10W-30 at temperatures above 0°F (−18°C).
When it is very cold, below 0°F (−18°C), you should
use SAE 5W-40 to improve cold starting. 5W-40
is not recommended for use at high temperatures,
above 100°F (38°C).
These numbers on the oil container show its
viscosity, or thickness. Do not use other viscosity
oils such as SAE 10W-40 or SAE 20W-50.
This doughnut-shaped
logo (symbol) is used on
most oil containers to
help you select the correct
oil. It means that the oil
has been certified by
the American Petroleum
Institute.
You should look for this on the oil container, and use
onlythose oils that display this logo.
GM Goodwrench
®oil of the recommended viscosity
grades meets all the requirements for your vehicle.
Engine Oil Additives
Do not add anything to your oil. The recommended oils
with the API service symbol are all you will need for
good performance and engine protection.
When to Change Engine Oil (Vehicles
Without the Engine Oil Life System)
If you have the 6.6L V8 (LLY) Engine: Change engine
oil and filter every 15,000 miles (24 000 km), or
every 12 months, or every 750 hours of engine
operation, whichever occurs first. If you have the
7.8L V6 (LG4) Engine: Change engine oil and filter
every 12,000 miles (20 000 km), or every 12 months, or
every 600 hours of engine operation, whichever
occurs first. SeeScheduled Maintenance on page 6-5.
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Engine Oil (Gasoline Engine)
If the low oil light appears
on the instrument cluster, it
means you need to
check your engine oil level
right away. For more
information, seeLow Oil
Level Light on page 3-39.
You should check your engine oil level regularly; this is
an added reminder.
Checking Engine Oil
It is 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.The engine oil dipstick is
located in the engine
compartment on the
driver’s side of the vehicle.
1. Turn off the engine and give the oil several minutes
to drain back into the oil pan. If you do not do this,
the oil dipstick might not show the actual level.
2. 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.
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When to Add Engine Oil
If the oil is below the cross-hatched area at the tip of
the dipstick, you will need to add at least one quart/liter
of oil. But you must use the right kind. This section
explains what kind of oil to use. For engine oil crankcase
capacity, seeCapacities and Speci cations on
page 5-99.
Notice:Do not add too much oil. If the engine has
so much oil that the oil level gets above the
cross-hatched area that shows the proper operating
range, the engine could be damaged.The engine oil fill cap is
located near the engine oil
dipstick in the engine
compartment, on the
driver’s side of the vehicle.
Be sure to add enough oil to put the level somewhere in
the proper operating range in the cross-hatched area.
Push the dipstick all the way back in when you are
through.
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What Kind of Engine Oil to Use
Look for two things:
•GM6094M
Your vehicle’s engine requires oil meeting GM
Standard GM6094M. You should 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 also
have the starburst
symbol on the container.
This symbol indicates
that the oil has been
certified by the American
Petroleum Institute (API).
You should look for this information on the oil container,
and useonlythose 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.
GM Goodwrench®oil meets all the requirements for
your vehicle.
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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 will provide
easier cold starting and better protection for your engine
at extremely low temperatures.
Engine Oil Additives
Do not add anything to your oil. The recommended oils
with the API service symbol are all you will 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. See
Change Engine Oil Light on page 3-40. Change your
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 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. Your dealer has GM-trained service people
who will perform this work using genuine GM parts and
reset the system. 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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How to Reset the Engine Oil
Life System
The Engine 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 light being turned on, reset the
system.
To reset the change engine oil light, do the following:
1. Turn the ignition key to RUN with the engine off.
2. Fully press and release the accelerator pedal slowly
three times within 10 seconds.
If the change engine oil light flashes for
five seconds, the system is resetting.
3. Turn the key to OFF.
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.
What to Do with Used Oil
Used engine oil contains certain elements that may 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 your used oil, ask
your dealer, a service station or a local recycling center
for help.
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Engine Oil Life System
(DURAMAX
®Diesel)
When to Change Engine Oil
If your vehicle has the Engine Oil Life System, it has a
computer system that lets you know when to change
the engine oil and filter. This is based on injection timing,
engine load 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. See
Change Engine Oil Light on page 3-40. Change your
oil as soon as possible within the next 600 miles
(1 000 km) or 30 hours of engine operation, whichever
occurs first. 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. Your dealer has GM-trained service people who
will perform this work using genuine GM parts and reset
the system. 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 15,000 miles (24 000 km), or
150 hours of engine operation, whichever occurs first,
since your last oil change. Remember to reset the oil life
system whenever the oil is changed.How to Reset the Engine Oil
Life System
The Engine 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 light being turned on, reset the
system.
To reset the Engine Oil Life System, do the following:
1. Turn the ignition key to RUN with the engine off.
2. Fully press and release the accelerator pedal slowly
three times within 10 seconds.
If the change engine oil light flashes for
five seconds, the system is resetting.
3. Turn the key to OFF.
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.
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