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When you tilt the hood far enough, the cables will
support it. When you close the hood, make
sure both latches are secured.
Engine Oil (Caterpillar®Diesel
Engine)
See your Caterpillar®Operation & Maintenance
Manual for information on oil quality and viscosities
as well as the temperature range chart.
Engine Oil (Gasoline Engine)
If the low oil light
appears on the
instrument cluster, it
means you need
to check the engine oil
level right away.
For more information, seeLow Oil Level Light on
page 176.
You should check the engine oil level regularly;
this is an added reminder.
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Checking Engine Oil
It is a good idea to check the 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.
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 347.
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.
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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.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.
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•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 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.
GM Goodwrench
®oil meets all the requirements
for your vehicle.
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 the engine at extremely low temperatures.
Engine Oil Additives
Do not add anything to the oil. The recommended
oils with the API service symbol are all you will
need for good performance and engine protection.
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Engine Oil (DURAMAX®/Isuzu Diesel
Engine)
Checking Engine Oil
It is a good idea to check the engine oil level
every time you get fuel.
The engine oil dipstick
is located in the engine
compartment on the
driver’s side of the
vehicle.In order to get an accurate reading, the engine
should be at normal operating temperature, so
that the oil is warm, and the vehicle must be
on level ground.
1. If the engine is at normal operating
temperature and the oil is warm, turn off the
engine and allow at least five minutes for
the oil to drain back into the oil pan. If you do
not do this, the oil dipstick might not show
the actual level.
If the engine has not been run long enough to
bring it up to normal operating temperature
and the oil is cool, turn off the engine and allow
30 minutes for the oil 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 a cloth, then push it back
in all the way.
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3. Remove the dipstick again, keeping the tip
down, and check the oil level.When to Add Engine Oil
If the oil is below the cross-hatched area at
the tip of the dipstick for the 6.6L V8 DURAMAX®
engine, you will need to add at least
two quarts/liters of oil. If the oil is below the
lower hole at the tip of the dipstick for the Isuzu
6H engine, 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 347.
Notice:Do not add too much oil. If the engine
has so much oil that the oil level gets above the
cross-hatched area for the 6.6L V8 (LLY) engine
or above the upper hole that shows the proper
operating range for the 7.8L L6 (LG4) engine,
the engine could be damaged.
6.6L V8 DURAMAX®Engine
Isuzu 6H Engine
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Add oil at the engine oil
fill cap in the engine
compartment. Install and
fully tighten the fill
cap when you
are through.
Be sure to add enough oil to put the level
somewhere in the proper operating range. Push
the dipstick all the way back in when you are
through.What Kind of Engine Oil to Use
Look for these two things:
•CJ-4 or CI-4
Oils designated as API CJ-4 or CI-4 are
recommended for your vehicle. The CJ-4 or
CI-4 designations may appear either
alone, together, or in combination with other
API designations, such as API CJ-4/SM.
These letters show American Petroleum
Institute (API) levels of quality.
Notice:Use only engine oils that have one of
these designations, CJ-4 or CI-4, for the
diesel engine. Failure to use the recommended
oils can result in engine damage not covered
by your warranty.
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GM Goodwrench®oil of the recommended
viscosity grades meets all the requirements for
your vehicle.
Engine Oil Additives
Do not add anything to the 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 DURAMAX®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 Isuzu 6H 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 363.
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 176. 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.
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