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3.6L V6 Engine Twin Turbo Engine
1. Engine Oil Fill Cap
2. Engine Cover
3. Engine Cover Bolt
To remove:1. Remove the oil fill cap (1).
2. Remove the engine cover bolt (3).
3. Raise the engine cover (2) to release it from the retainers.
4. Lift and remove the engine cover.
5. Reverse Steps 1–4 to reinstall the engine cover.
Engine Oil
To ensure proper engine performance
and long life, careful attention must
be paid to engine oil. Following these
simple, but important steps will help
protect your investment:
.Use engine oil approved to the
proper specification and of the
proper viscosity grade. See
“Selecting the Right Engine Oil” in
this section.
. Check the engine oil level regularly
and maintain the proper oil level.
See “Checking Engine Oil” and
“When to Add Engine Oil” in this
section.
. Change the engine oil at the
appropriate time. See Engine Oil
Life System 0242.
. Always dispose of engine oil
properly. See “What to Do with
Used Oil” in this section.
Checking Engine Oil
Check the engine oil level regularly,
every 650 km (400 mi), especially prior
to a long trip. The engine oil dipstick handle is a loop. See
Engine
Compartment Overview 0236 for the
location.
{Warning
The engine oil dipstick handle may
be hot; it could burn you. Use a
towel or glove to touch the dipstick
handle.
If a low oil Driver Information Center
(DIC) message displays, check the oil
level.
Follow these guidelines:
. To get an accurate reading, park
the vehicle on level ground. Check
the engine oil level after the
engine has been off for at least
two hours. Checking the engine oil
level on steep grades or too soon
after engine shutoff can result in
incorrect readings. Accuracy
improves when checking a cold
engine prior to starting. Remove
the dipstick and check the level.
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.If unable to wait two hours, the
engine must be off for at least
15 minutes if the engine is warm,
or at least 30 minutes if the
engine is not warm. Pull out the
dipstick, wipe it with a clean 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
3.6L V6 Engine
3.6L V6 Twin Turbo Engine If the oil is below the cross-hatched
area at the tip of the dipstick and the
engine has been off for at least
15 minutes, add 1 L (1 qt) of the
recommended oil and then recheck
the level. See
“Selecting the Right
Engine Oil” later in this section for an
explanation of what kind of oil to use.
For engine oil crankcase capacity, see
Capacities and Specifications 0331.
Caution
Do not add too much oil. Oil levels
above or below the acceptable
operating range shown on the
dipstick are harmful to the engine.
If you find that you have an oil
level above the operating range, i.e.,
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. You should
drain out the excess oil or limit
driving of the vehicle and seek a
service professional to remove the
excess amount of oil. See
Engine Compartment Overview
0 236 for the location of the engine oil
fill cap.
Add enough oil to put the level
somewhere in the proper operating
range. Push the dipstick all the way
back in when through.
Selecting the Right Engine Oil
Selecting the right engine oil depends
on both the proper oil specification
and viscosity grade. See Recommended
Fluids and Lubricants 0326.
Specification
Ask for and use engine oils that meet
the dexos1™ specification. Engine oils
that have been approved by GM as
meeting the dexos1 specification are
marked with the dexos1 approved
logo. See www.gmdexos.com.
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Caution
Failure to use the recommended
engine oil or equivalent can result
in engine damage not covered by
the vehicle warranty.
Viscosity Grade
Use SAE 5W-30 viscosity grade
engine oil.
Cold Temperature Operation: In an
area of extreme cold, where the
temperature falls below −29 °C
(−20 °F), an SAE 0W-30 oil may be
used. An oil of this viscosity grade will
provide easier cold starting for the
engine at extremely low temperatures.
When selecting an oil of the
appropriate viscosity grade, it is
recommended to select an oil of the
correct specification. See
“Specification ”earlier in this section.
Engine Oil Additives/Engine Oil
Flushes
Do not add anything to the oil. The
recommended oils meeting the dexos1
specification are all that is needed for
good performance and engine
protection.
Engine oil system flushes are not
recommended and could cause engine
damage not covered by the vehicle
warranty.
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
or pouring it on the ground, into
sewers, or into streams or bodies of
water. Recycle it by taking it to a place
that collects used oil.
Engine Oil Life System
When to Change Engine Oil
This vehicle has a computer system
that indicates when to change the
engine oil and filter. This is based on a
combination of factors which include
engine revolutions, engine
temperature, and miles driven. Based
on driving conditions, the mileage at
which an oil change is indicated can
vary considerably. For the oil life
system to work properly, the system
must be reset every time the oil is
changed.
When the system has calculated that
oil life has been diminished, it
indicates that an oil change is
necessary. A CHANGE ENGINE OIL
SOON message comes on. Change the
oil as soon as possible within the next
1 000 km (600 mi). It is possible that,
if driving under the best conditions,
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the oil life system might indicate that
an oil change is not necessary for up
to a year. The engine oil and filter
must be changed at least once a year
and at this time the system must be
reset. Your dealer has trained service
people who will perform this work and
reset the system. It is also important
to check the oil regularly over the
course of an oil drain interval and
keep it at the proper level.
If the system is ever reset accidentally,
the oil must be changed at 5 000 km
(3,000 mi) since the last oil change.
Remember to reset the oil life system
whenever the oil is changed.
How to Reset the Engine Oil Life
System
Reset the system whenever the engine
oil is changed so that the system can
calculate the next engine oil change.
To reset the system:1. Using the DIC buttons, display REMAINING OIL LIFE on the
DIC. See Driver Information Center
(DIC) 0136. 2. Press and hold SEL to clear the
CHANGE ENGINE OIL SOON
message and reset the oil life
at 100%.
Be careful not to reset the oil life
display accidentally at any time
other than after the oil is
changed. It cannot be reset
accurately until the next oil
change.
The oil life system can also be reset as
follows: 1. Display REMAINING OIL LIFE on the DIC. See Driver Information
Center (DIC) 0136.
2. Fully press and release the accelerator pedal three times
within five seconds.
If the CHANGE ENGINE OIL
SOON message is not on, the
system is reset.
The system is reset when the
CHANGE ENGINE OIL SOON message
is off. If the CHANGE ENGINE OIL SOON
message comes back on when the
vehicle is started, the engine oil life
system has not been reset. Repeat the
procedure.
Automatic Transmission
Fluid
A transmission fluid leak is the only
reason for fluid loss. If a leak occurs,
take the vehicle to your dealer and
have it repaired as soon as possible.
See your dealer to have the fluid and
filter changed at the intervals listed in
the
Maintenance Schedule 0317.
Engine Air Cleaner/Filter
The engine air cleaner/filter is in the
engine compartment on the passenger
side of the vehicle. See Engine
Compartment Overview 0236.
When to Inspect the Engine Air
Cleaner/Filter
For intervals on changing and
inspecting the engine air cleaner/filter,
see Maintenance Schedule 0317.
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How to Inspect the Engine Air
Cleaner/Filter
Do not start the engine or have the
engine running with the engine air
cleaner/filter housing open. Before
removing the engine air cleaner/filter,
make sure that the engine air cleaner/
filter housing and nearby components
are free of dirt and debris. Remove the
engine air cleaner/filter. Lightly tap
and shake the engine air cleaner/filter
(away from the vehicle), to release
dust and dirt. Inspect the engine air
cleaner/filter for damage, and replace
if damaged. Do not clean the engine
air cleaner/filter or components with
water or compressed air.To inspect or replace the engine air
cleaner/filter:
3.6L V6 Engine
1. Remove the seven screws on top of the engine air cleaner/filter
housing.
2. Lift the air cleaner/filter cover housing away from the engine.
3. Pull out the filter.
4. Inspect or replace the engine air cleaner/filter.
5. Reverse Steps 1–3 to reinstall the filter cover housing.
3.6L V6 Twin Turbo Engine
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1. Screws
2. Secondary Air Hose
3. Lower Air Duct Clamp
4. Lower Electrical Connector
5. Upper Electrical Connector
6. Upper Air Duct Clamp
1. Disconnect the lower and upperoutlet ducts by loosening the
lower (3) and upper (6) air duct
clamps.
2. Disconnect the lower (4) and upper (5) electrical connectors
and wiring attachments from the
air cleaner/filter cover.
3. Remove the screws (1) on top of the air cleaner/filter cover.
4. Lift the air cleaner/filter cover housing away from the engine.
5. Pull out the air cleaner/filter.
6. Inspect or replace the engine air cleaner/filter.
7. Reverse Steps 1–5 to reinstall the air cleaner/filter cover housing.
{Warning
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 helps to
stop flames if the engine backfires.
Use caution when working on the
engine and do not drive with the air
cleaner/filter off.
Caution
If the air cleaner/filter is off, dirt
can easily get into the engine,
which could damage it. Always have
the air cleaner/filter in place when
driving.
Cooling System
The cooling system allows the engine
to maintain the correct working
temperature.
3.6L V6 Engine
1. Electric Engine Cooling Fans
(Out of View)
2. Coolant Surge Tank and Pressure Cap
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3.6L V6 Twin Turbo Engine
1. Electric Engine Cooling Fans(Out of View)
2. Charged Air Coolant (CAC) Bottle and Pressure Cap
3. Coolant Surge Tank and Pressure Cap
{Warning
An underhood electric fan can start
up even when the engine is not
running and can cause injury. Keep
hands, clothing, and tools away
from any underhood electric fan.
{Warning
Do not touch heater or radiator
hoses, or other engine parts. They
can be very hot and can burn you.
Do not run the engine if there is a
leak; all coolant could leak out.
That could cause an engine fire and
can burn you. Fix any leak before
driving the vehicle.
Engine Coolant
The engine and Charged Air Coolant
(CAC) cooling systems in the vehicle
are filled with DEX-COOL engine
coolant mixture.
See Recommended Fluids and
Lubricants 0326 and Maintenance
Schedule 0317.
The following explains the cooling
systems and how to check and add
coolant when it is low. If there is a
problem with engine overheating, see
Engine Overheating 0249.
What to Use
{Warning
Plain water, or other liquids such as
alcohol, can boil before the proper
coolant mixture will. With plain
water or the wrong mixture, the
engine could get too hot but there
would not be an overheat warning.
The engine could catch fire and you
or others could be burned.
Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
coolant. This mixture:
. Gives freezing protection down to
−37 °C (−34 °F), outside
temperature.
. Gives boiling protection up to 129
°C (265 °F), engine temperature.
. Protects against rust and
corrosion.
. Will not damage aluminum parts.
. Helps keep the proper engine
temperature.
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Caution
Do not use anything other than a
mix of DEX-COOL coolant that
meets GM Standard GMW3420 and
clean, drinkable water. Anything
else can cause damage to the
engine cooling system and the
vehicle, which would not be covered
by the vehicle warranty.
Never dispose of engine coolant by
putting it in the trash, pouring it on
the ground, or pouring into sewers,
streams, or bodies of water. Have the
coolant changed by an authorized
service center, familiar with legal
requirements regarding used coolant
disposal. This will help protect the
environment and your health.
Checking Coolant
The vehicle must be on a level surface
when checking the coolant level.
The engine coolant surge tank and
CAC bottle are in the engine
compartment on the driver side of the
vehicle. See Engine Compartment
Overview 0236.
Check to see if coolant is visible in the
surge tank and CAC bottle. If the
coolant inside the surge tank is
boiling, do not do anything else until
it cools down. If coolant is visible but
the coolant level is not at or above the
mark pointed to on the surge tank or
at the CAC bottle cold fill mark, add a
50/50 mixture of clean, drinkable
water and DEX-COOL coolant.
Be sure the cooling system is cool
before this is done. If no coolant is visible in the coolant
surge tank or CAC bottle, add coolant
as follows:
How to Add Coolant to the
Surge Tank
{Warning
Plain water, or other liquids such as
alcohol, can boil before the proper
coolant mixture will. With plain
water or the wrong mixture, the
engine could get too hot but there
would not be an overheat warning.
The engine could catch fire and you
or others could be burned.
{Warning
Spilling coolant on hot engine parts
can burn you. Coolant contains
ethylene glycol and it will burn if
the engine parts are hot enough.