
This vehicle has an airbag system. Before attempting
to do your own service work, seeServicing Your
Airbag-Equipped Vehicle on page 2-72.
Keep a record with all parts receipts and list the
mileage and the date of any service work performed.
SeeMaintenance Record on page 7-13.Adding Equipment to the Outside of
the VehicleThings added to the outside of the vehicle can affect the
airflow around it. This can cause wind noise and can
affect fuel economy and windshield washer performance.
Check with your dealer/retailer before adding equipment
to the outside of the vehicle.FuelUse of the recommended fuel is an important part of the
proper maintenance of this vehicle. To help keep the
engine clean and maintain optimum vehicle performance,
we recommend the use of gasoline advertised as TOP
TIER Detergent Gasoline.
Look for the TOP TIER label on the fuel pump to ensure
gasoline meets enhanced detergency standards
developed by auto companies. A list of marketers
providing TOP TIER Detergent Gasoline can be found
at www.toptiergas.com.The 8th digit of the Vehicle Identification Number (VIN)
shows the code letter or number that identifies the
vehicle’s engine. The VIN is at the top left of the
instrument panel. SeeVehicle Identification Number
(VIN) on page 6-95.
If the vehicle has the 3.5L V6 engine (VIN Code K) or
the 3.9L V6 engine (VIN Code M), you can use
either unleaded gasoline or ethanol fuel containing up to
85% ethanol (E85). SeeFuel E85 (85% Ethanol) on
page 6-8. In all other engines, use only the unleaded
gasoline described underGasoline Octane on page 6-6.
6-5

Gasoline OctaneUse regular unleaded gasoline with a posted octane
rating of 87 or higher. If the octane rating is less than 87,
an audible knocking noise, commonly referred to as spark
knock, might be heard when driving. If this occurs, use a
gasoline rated at 87 octane or higher as soon as possible.
If heavy knocking is heard when using gasoline rated at
87 octane or higher, the engine needs service.Gasoline SpecificationsAt a minimum, gasoline should meet ASTM specification
D 4814 in the United States or CAN/CGSB-3.5 or 3.511 in
Canada. Some gasolines contain an octane-enhancing
additive called methylcyclopentadienyl manganese
tricarbonyl (MMT). We recommend against the use of
gasolines containing MMT. SeeAdditives on page 6-7
for additional information.
California FuelIf the vehicle is certified to meet California Emissions
Standards, it is designed to operate on fuels that meet
California specifications. See the underhood emission
control label. If this fuel is not available in states adopting
California emissions standards, the vehicle will operate
satisfactorily on fuels meeting federal specifications, but
emission control system performance might be affected.
The malfunction indicator lamp could turn on and the
vehicle might fail a smog-check test. SeeMalfunction
Indicator Lamp on page 4-31. If this occurs, return to your
authorized dealer/retailer for diagnosis. If it is determined
that the condition is caused by the type of fuel used,
repairs might not be covered by the vehicle warranty.
6-6

AdditivesTo provide cleaner air, all gasolines in the United States
are now required to contain additives that help prevent
engine and fuel system deposits from forming, allowing
the emission control system to work properly. In most
cases, nothing should have to be added to the fuel.
However, some gasolines contain only the minimum
amount of additive required to meet U.S. Environmental
Protection Agency regulations. To help keep fuel injectors
and intake valves clean, or if the vehicle experiences
problems due to dirty injectors or valves, look for gasoline
that is advertised as TOP TIER Detergent Gasoline.
For customers who do not use TOP TIER Detergent
Gasoline regularly, one bottle of GM Fuel System
Treatment PLUS, added to the fuel tank at every engine
oil change, can help clean deposits from fuel injectors
and intake valves. GM Fuel System Treatment PLUS
is the only gasoline additive recommended by
General Motors.
Also, your dealer/retailer has additives that will help
correct and prevent most deposit-related problems.Gasolines containing oxygenates, such as ethers and
ethanol, and reformulated gasolines might be available in
your area. We recommend that you use these gasolines,
if they comply with the specifications described earlier.
However, E85 (85% ethanol) and other fuels containing
more than 10% ethanol must not be used in vehicles that
were not designed for those fuels.
Notice:This vehicle was not designed for fuel that
contains methanol. Do not use fuel containing
methanol. It can corrode metal parts in the fuel
system and also damage plastic and rubber parts.
That damage would not be covered under the
vehicle warranty.
Some gasolines that are not reformulated for low
emissions can contain an octane-enhancing additive
called methylcyclopentadienyl manganese tricarbonyl
(MMT); ask the attendant where you buy gasoline
whether the fuel contains MMT. We recommend against
the use of such gasolines. Fuels containing MMT can
reduce the life of spark plugs and the performance
of the emission control system could be affected.
The malfunction indicator lamp might turn on. If this
occurs, return to your dealer/retailer for service.
6-7

Fuel E85 (85% Ethanol)The 8th digit of the Vehicle Identification Number (VIN)
shows the code letter or number that identifies the
vehicle’s engine. The VIN is at the top left of the
instrument panel. SeeVehicle Identification Number
(VIN) on page 6-95.
If the vehicle has the 3.5L V6 engine (VIN Code K)
or the 3.9L V6 engine (VIN Code M), you can use either
unleaded gasoline or ethanol fuel containing up to
85% ethanol (E85). SeeFuel on page 6-5. In all other
engines, use only the unleaded gasoline described
underGasoline Octane on page 6-6.
Only vehicles that have the 3.5L V6 engine (VIN Code K)
or the 3.9L V6 engine (VIN Code M) can use 85% ethanol
fuel (E85). We encourage the use of E85 in vehicles
that are designed to use it. The ethanol in E85 is a
“renewable” fuel, meaning it is made from renewable
sources such as corn and other crops.
Many service stations will not have an 85% ethanol
fuel (E85) pump available. The U.S. Department
of Energy has an alternative fuels website
(www.eere.energy.gov/afdc/infrastructure/locator.html)
that can help you find E85 fuel. Those stations that
do have E85 should have a label indicating ethanol
content. Do not use the fuel if the ethanol content
is greater than 85%.At a minimum, E85 should meet ASTM Specification
D 5798. By definition, this means that fuel labeled E85
will have an ethanol content between 70% and 85%.
Filling the fuel tank with fuel mixtures that do not meet
ASTM specifications can affect driveability and could
cause the malfunction indicator lamp to come on.
To ensure quick starts in the wintertime, the E85 fuel
must be formulated properly for your climate according to
ASTM specification D 5798. If you have trouble starting
on E85, it could be because the E85 fuel is not properly
formulated for your climate. If this happens, switching to
gasoline or adding gasoline to the fuel tank can improve
starting. For good starting and heater efficiency below
32°F (0°C), the fuel mix in the fuel tank should contain
no more than 70% ethanol. It is best not to alternate
repeatedly between gasoline and E85. If you do switch
fuels, it is recommended that you add as much fuel as
possible — do not add less than three gallons (11 L)
when refueling. You should drive the vehicle immediately
after refueling for at least seven miles (11 km) to allow the
vehicle to adapt to the change in ethanol concentration.
6-8

Engine Oil Additives / Engine Oil
FlushesDo 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 SystemWhen to Change Engine OilThis 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
600 miles (1 000 km). 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 3,000 miles (5 000 km) since the last oil
change. Remember to reset the oil life system whenever
the oil is changed.
6-18

Automatic Transmission FluidWhen to Check and Change Automatic
Transmission FluidA good time to check your 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 7-3, and be sure to
use the transmission fluid listed inRecommended Fluids
and Lubricants on page 7-10.How to Check Automatic Transmission
FluidBecause this operation can be a little difficult, you may
choose to have this done at the dealer/retailer service
department.
If you do it yourself, be sure to follow all the instructions
here, or you could get a false reading on the dipstick.Notice:Too much or too little fluid can damage
your transmission. Too much can mean that some
of the fluid could come out and fall on hot engine
parts or exhaust system parts, starting a fire.
Too little fluid could cause the transmission to
overheat. Be sure to get an accurate reading if you
check your transmission fluid.
Wait at least 30 minutes before checking the
transmission fluid level if you have been driving:
•
When outside temperatures are above 32°C (90°F).
•
At high speed for quite a while.
•
In heavy traffic — especially in hot weather.
•
While pulling a trailer.
To get the right reading, the fluid should be at normal
operating temperature, which is 82°C to 93°C
(180°F to 200°F).
Get the vehicle warmed up by driving about 24 km
(15 miles) when outside temperatures are above 10°C
(50°F). If it is colder than 10°C (50°F), you may have to
drive longer.
6-22

4. Then fill the coolant recovery tank to the
COLD FILL line.
5. Install the coolant recovery tank cap and the
pressure cap. After a day or two of driving, when the
engine is cold, check the coolant level in the recovery
tank. If it is low, refill it to the COLD FILL line.If the coolant in the recovery tank is constantly low,
you should have a dealer/retailer service department
inspect the vehicle for leaks.
Notice:If the pressure cap is not tightly installed,
coolant loss and possible engine damage may occur.
Be sure the cap is properly and tightly secured.
Engine OverheatingThe vehicle has several indicators to warn of engine
overheating.
There is a coolant temperature gage and a warning light
on the instrument panel that indicate an overheated
engine condition. SeeEngine Coolant Temperature
Gage on page 4-30Engine Coolant Temperature Gage
andEngine Coolant Temperature Warning Light on
page 4-30Engine Coolant Temperature Warning Light.
6-29

In addition, you will find an ENGINE OVERHEATED
IDLE ENGINE and an ENGINE OVERHEATED STOP
ENGINE message displayed on the vehicle’s Driver
Information Center (DIC). SeeDIC Warnings and
Messages on page 4-44DIC Warnings and Messages
for more information.
You may decide not to lift the hood when this warning
appears, but instead get service help right away.
SeeRoadside Assistance Program on page 8-7.
If you do decide to lift the hood, make sure the vehicle
is parked on a level surface.
Then check to see if the engine cooling fans are
running. If the engine is overheating, both fans should
be running. If they are not, do not continue to run
the engine and have the vehicle serviced.
Notice:Engine damage from running the engine
without coolant is not covered by the warranty.
Notice:If the engine catches fire while driving with
no coolant, the vehicle can be badly damaged.
The costly repairs would not be covered by
the vehicle warranty. SeeOverheated Engine
Protection Operating Mode on page 6-32for
information on driving to a safe place in an
emergency.
If Steam Is Coming From The Engine
Compartment
{
WARNING:
Steam from an overheated engine can burn you
badly, even if you just open the hood. Stay away
from the engine if you see or hear steam coming
from it. Turn it off and get everyone away from the
vehicle until it cools down. Wait until there is no sign
of steam or coolant before you open the hood.
If you keep driving when the vehicles engine is
overheated, the liquids in it can catch fire. You or
others could be badly burned. Stop the engine if it
overheats, and get out of the vehicle until the
engine is cool.
SeeOverheated Engine Protection Operating Mode
on page 6-32for information on driving to a safe
place in an emergency.
6-30