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{WARNING:
Fuel can spray out on you if you open the fuel cap
too quickly. If you spill fuel and then something
ignites it, you could be badly burned. This spray
can happen if the tank is nearly full, and is more
likely in hot weather. Open the fuel cap slowly and
wait for any hiss noise to stop. Then unscrew the
cap all the way.
Be careful not to spill fuel. Do not top off or overfill the
tank and wait a few seconds after you have finished
pumping before removing the nozzle. Clean fuel from
painted surfaces as soon as possible. SeeWashing
Your Vehicle on page 6-105.
When replacing the fuel cap, turn it clockwise until it
clicks. Make sure the cap is fully installed. The diagnostic
system can determine if the fuel cap has been left off or
improperly installed. This would allow fuel to evaporate
into the atmosphere. SeeMalfunction Indicator Lamp on
page 4-30.
{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 t
properly. This may cause the malfunction indicator
lamp to light and may damage the fuel tank and
emissions system. SeeMalfunction Indicator Lamp
on page 4-30.
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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.
Checking Things Under
the Hood
{WARNING:
Things that burn can get on hot engine or fuel
operated heater (FOH) 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 or fuel operated heater (FOH).
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Page 283 of 440
Hood Release
To open the hood:
1. Pull the handle with
this symbol on it. It is
located in front of
the driver’s side door
frame near the floor.
2. Then go to the front of the vehicle and lift up
the secondary hood release, which is located
underneath the middle of the hood.3. Lift the hood, release the hood prop from its
retainer and put the hood prop into the slot in
the hood.
If your vehicle has an underhood lamp, it will
automatically come on and stay on until the hood
is closed.
Before closing the hood, be sure all of the filler caps are
on properly. Then lift the hood to relieve pressure on the
hood prop. Remove the hood prop from the slot in the
hood and return the prop to its retainer. Let the hood
down and close it firmly.
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Engine Compartment Overview
If the vehicle has a diesel engine, see the maintenance schedule section in the DURAMAX®Diesel manual.
When the hood is lifted:
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Page 285 of 440

A. Battery. SeeBattery on page 6-43.
B. Radiator Pressure Cap. SeeCooling System on
page 6-28.
C. Coolant Recovery Tank. SeeCooling System on
page 6-28.
D. Automatic Transmission Fluid Dipstick. See
“Checking the Fluid Level” underAutomatic
Transmission Fluid (4-Speed Transmission)
on page 6-21orAutomatic Transmission Fluid
(6-Speed Transmission) on page 6-24.
E. Engine Oil Fill Cap. See “When to Add Engine Oil”
underEngine Oil on page 6-15.
F. Engine Oil Dipstick. See “Checking Engine Oil”
underEngine Oil on page 6-15.
G. Engine Air Cleaner/Filter. SeeEngine Air
Cleaner/Filter on page 6-20.
H. Power Steering Fluid Reservoir. SeePower Steering
Fluid on page 6-38.
I. Brake Master Cylinder Reservoir. See “Brake Fluid”
underBrakes on page 6-40.
J. Windshield Washer Fluid Reservoir. See “Adding
Washer Fluid” underWindshield Washer Fluid
on page 6-39.Engine Oil
For diesel engine vehicles, see “Engine Oil” in the
DURAMAX®Diesel manual.
Checking Engine Oil
It is a good idea to check the engine oil level at each
fuel fill. In order to get an accurate reading, the oil must
be warm and the vehicle must be on level ground.
The engine oil dipstick handle is a yellow loop.
SeeEngine Compartment Overview on page 6-14
for the location of the engine oil dipstick.
1. Turn off the engine and give the oil several minutes
to drain back into the oil pan. If this is not done, 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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Page 286 of 440
When to Add Engine Oil
If the oil is below the cross-hatched area at the tip of the
dipstick, add at least one quart/liter of the recommended
oil. This section explains what kind of oil to use. For
engine oil crankcase capacity, seeCapacities and
Speci cations on page 6-116.
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.SeeEngine Compartment
Overview on page 6-14
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.
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What Kind of Engine Oil to Use
Look for three things:
•GM6094M
Use only an oil that meets GM Standard GM6094M.
•SAE 5W-30
SAE 5W-30 is best for the vehicle. These numbers
on an oil container show its viscosity, or thickness.
Do not use other viscosity oils such as SAE 20W-50.
•American Petroleum Institute (API) starburst symbol
Oils meeting these
requirements should have
the starburst symbol on the
container. This symbol
indicates that the oil has
been certified by the
American Petroleum
Institute (API).
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
the vehicle warranty.
Cold Temperature Operation
If in an area of extreme cold, where the temperature
falls below−20°F (−29°C), use either an SAE 5W-30
synthetic oil or an SAE 0W-30 engine oil. Both provide
easier cold starting for the engine at extremely low
temperatures. Always use an oil that meets the required
specification, GM6094M. See “What Kind of Engine
Oil to Use” for more information.
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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.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.
SeeDIC Warnings and Messages on page 4-44. 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. 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.
6-18