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The TIGHTEN GAS CAP message displays on the
Driver Information Center (DIC) if the fuel cap is not
properly installed. SeeDIC Warnings and Messages
on
page 4‑65for more information.
{WARNING:
If a fire starts while you are refueling, do not
remove the nozzle. Shut off the flow of fuel by
shutting off the pump or by notifying the station
attendant. Leave the area immediately.
Notice: If you need a new fuel cap, be sure to get
the right type. Your dealer/retailer can get one for
you. If you get the wrong type, it may not fit
properly. This may cause the malfunction indicator
lamp to light and may damage the fuel tank and
emissions system. See Malfunction Indicator Lamp
on page 4‑42.
Filling a Portable Fuel Container
{WARNING:
Never fill a portable fuel container while it is in the
vehicle. Static electricity discharge from the
container can ignite the fuel vapor. You can be
badly burned and the vehicle damaged if this
occurs. To help avoid injury to you and others:
.Dispense fuel only into approved containers.
.Do not fill a container while it is inside a
vehicle, in a vehicle's trunk, pickup bed, or on
any surface other than the ground.
.Bring the fill nozzle in contact with the inside
of the fill opening before operating the nozzle.
Contact should be maintained until the filling
is complete.
.Do not smoke while pumping fuel.
.Do not use a cellular phone while
pumping fuel.
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Checking Things Under
the Hood
{WARNING:
An electric fan under the hood can start up and
injure you even when the engine is not running.
Keep hands, clothing, and tools away from any
underhood electric fan.
{WARNING:
Things that burn can get on hot engine parts and
start a fire. These include liquids like fuel, oil,
coolant, brake fluid, windshield washer and other
fluids, and plastic or rubber. You or others could
be burned. Be careful not to drop or spill things
that will burn onto a hot engine.
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Engine Oil Additives / Engine Oil
Flushes
Do not add anything to the oil. The recommended oils
with the starburst symbol that meet GM Standard
GM6094M 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.
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
engine revolutions and engine temperature, and not on
mileage. 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.
On some vehicles, when the system has calculated that
oil life has been diminished, a CHANGE ENGINE OIL
SOON message comes on to indicate that an oil
change is necessary. SeeDIC Warnings and Messages
on page 4‑65. Change the oil as soon as possible
within the next 1 000 km (600 miles). It is possible that, if 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. For vehicles without the
CHANGE ENGINE OIL SOON message, An oil change
is needed when the OIL LIFE REMAINING percentage
is near 0%. 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, the oil must be
changed at 5 000 km (3,000 miles) 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
The Engine Oil Life System calculates when to
change the engine oil and filter based on vehicle use.
Whenever the oil is changed, reset the system so it can
calculate when the next oil change is required. If a
situation occurs where the oil is changed prior to a
CHANGE ENGINE OIL SOON message coming on,
reset the system.
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Always reset the engine oil life to 100% after every oil
change. It will not reset itself. To reset the Engine Oil
Life System on most vehicles:1. Display the OIL LIFE REMAINING on the DIC. If the vehicle does not have DIC buttons, the
vehicle must be in P (Park) to access this display.
See DIC Operation and Displays (With DIC
Buttons)
on page 4‑51or DIC Operation and
Displays (Without DIC Buttons) on page 4‑58.
2. Press and hold the SET/RESET button on the DIC, or the trip odometer reset stem if the vehicle does
not have DIC buttons, for more than five seconds.
The oil life will change to 100%.
On all vehicles, the Engine Oil Life System can be reset
as follows: 1. Turn the ignition to ON/RUN with the engine off
2. Fully press the accelerator pedal slowly three times within five seconds.
3. Display the OIL LIFE REMAINING on the DIC. If the display shows 100%, the system is reset.
See DIC Operation and Displays (With DIC
Buttons)
on page 4‑51or DIC Operation and
Displays (Without DIC Buttons) on page 4‑58. If the vehicle has a CHANGE ENGINE OIL SOON
message and it comes back on when the vehicle is
started and/or the OIL LIFE REMAINING is near 0%,
the Engine Oil Life System has not reset. Repeat the
procedure.
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. Recycle it by taking it to a
place that collects used oil.
Engine Air Cleaner/Filter
If the vehicle has a diesel engine, see
“Pickup Models”
under “Engine Air Cleaner/Filter” in the DURAMAX®
Diesel Supplement for the correct inspection and
replacement procedures.
SeeEngine Compartment Overview
on page 6‑16for
the location of the engine air cleaner/filter.
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3. Remove the engine air cleaner/filter from thehousing. Care should be taken to dislodge as little
dirt as possible.
4. Clean the engine air cleaner/filter sealing surfaces and the housing.
5. Inspect or replace the engine air cleaner/filter.
6. Reinstall the cover and tighten the screws.
{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.
Automatic Transmission Fluid
(4-Speed Transmission)
When to Check and Change Automatic
Transmission Fluid
A good time to check the automatic transmission fluid
level is when the engine oil is changed.
Change the fluid and filter at the intervals listed in
Scheduled Maintenance
on page 7‑3and be sure to
use the transmission fluid listed in Recommended
Fluids and Lubricants on page 7‑12.
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Cooling System
If your vehicle has the DURAMAX®Diesel engine, see
the DURAMAX®Diesel manual for more information.
The Cooling System allows the engine to maintain the
correct working temperature.
5.3L Engine (4.3L, 4.8L, 6.0L and 6.2L Similar)
A. Coolant Surge Tank
B. Coolant Surge Tank Pressure Cap
C. Engine Cooling Fan
{WARNING:
An electric engine cooling fan can start even
when the engine is not running. To avoid injury,
always keep hands, clothing, and tools away from
any engine cooling fan.
{WARNING:
Heater and radiator hoses, and other engine
parts, can be very hot. Do not touch them.
If you do, you can be burned.
Do not run the engine if there is a leak. If you run
the engine, it could lose all coolant. That could
cause an engine fire, and you could be burned.
Get any leak fixed before you drive the vehicle.
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Notice:Using coolant other than DEX-COOL®can
cause premature engine, heater core, or radiator
corrosion. In addition, the engine coolant could
require changing sooner, at 50 000 km (30,000 miles)
or 24 months, whichever occurs first. Any repairs
would not be covered by the vehicle warranty.
Always use DEX-COOL
®(silicate-free) coolant in
the vehicle.
Engine Coolant
The cooling system in the vehicle is filled with
DEX-COOL®engine coolant. This coolant is designed
to remain in the vehicle for five years or 150,000 miles
(240 000 km), whichever occurs first.
The following explains the cooling system and how to
check and add coolant when it is low. If there is a
problem with engine overheating, see Engine
Overheating on page 6‑34.
What to Use
{WARNING:
Adding only plain water to the cooling system can
be dangerous. Plain water, or some other liquid
such as alcohol, can boil before the proper
coolant mixture will. The vehicle's coolant warning
system is set for the proper coolant mixture. With
plain water or the wrong mixture, the engine could
get too hot but you would not get the 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.
Use a 50/50 mixture of clean, drinkable water and
DEX-COOL
®coolant. If using this mixture, nothing else
needs to be added. This mixture:
.Gives freezing protection down to −34°F (−37°C),
outside temperature.
.Gives boiling protection up to 265°F (129°C),
engine temperature.
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.Protects against rust and corrosion.
.Will not damage aluminum parts.
.Helps keep the proper engine temperature.
Notice: If an improper coolant mixture is used, the
engine could overheat and be badly damaged. The
repair cost would not be covered by the vehicle
warranty. Too much water in the mixture can freeze
and crack the engine, radiator, heater core, and
other parts.
Notice: If extra inhibitors and/or additives are used
in the vehicle's cooling system, the vehicle could be
damaged. Use only the proper mixture of the engine
coolant listed in this manual for the cooling system.
See Recommended Fluids and Lubricants
on
page 7‑12for more information.
Checking Coolant
The coolant surge tank is located in the engine
compartment on the passenger side of the vehicle. See
Engine Compartment Overview
on page 6‑16for more
information on location.
The vehicle must be on a level surface when checking
the coolant level.
Check to see if coolant is visible in the coolant surge
tank. If the coolant inside the coolant 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 FULL COLD mark, add a 50/50 mixture of
clean, drinkable water and DEX-COOL
®coolant at the
coolant surge tank, but be sure the cooling system is
cool before this is done.
The coolant level should be at or above the FULL
COLD mark. If it is not, you may have a leak in the
cooling system.
If the vehicle has a low coolant sensor and the LOW
COOLANT LEVEL message comes on and stays on, it
means you are low on engine coolant. See “LOW
COOLANT LEVEL” underDIC Warnings and Messages
on page 4‑65.
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