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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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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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