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Service
Your dealer knows your vehicle best and wants you to
be happy with it. We hope you will go to your dealer
for all your service needs. You will get genuine GM parts
and GM-trained and supported service people.
We hope you will want to keep your GM vehicle all GM.
Genuine GM parts have one of these marks:
Accessories and Modi cations
When you add non-GM accessories to your vehicle they
can affect your vehicle’s performance and safety,
including such things as, braking, stability, ride and
handling, emissions systems, aerodynamics, durability,
and electronic systems like antilock brakes, traction
control and stability control. Some of these accessories
may even cause malfunction or damage not covered
by warranty.
GM Accessories are designed to complement and
function with other systems on your vehicle. Your
GM dealer can accessorize your vehicle using genuine
GM Accessories. When you go to your GM dealer
and ask for GM Accessories, you will know that
GM-trained and supported service technicians will
perform the work using genuine GM Accessories.
California Proposition 65 Warning
Most motor vehicles, including this one, contain and/or
emit chemicals known to the State of California to
cause cancer and birth defects or other reproductive
harm. Engine exhaust, many parts and systems
(including some inside the vehicle), many uids, and
some component wear by-products contain and/or
emit these chemicals.
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Doing Your Own Service Work
{CAUTION:
You can be injured and your vehicle could be
damaged if you try to do service work on a
vehicle without knowing enough about it.
Be sure you have sufficient knowledge,
experience, the proper replacement parts,
and tools before you attempt any vehicle
maintenance task.
Be sure to use the proper nuts, bolts,
and other fasteners. English and metric
fasteners can be easily confused. If you
use the wrong fasteners, parts can later
break or fall off. You could be hurt.
If you want to do some of your own service work, you will
want to use the proper service manual. It tells you much
more about how to service your vehicle than this manual
can. To order the proper service manual, seeService
Publications Ordering Information on page 7-15.
Your vehicle has an airbag system. Before attempting
to do your own service work, seeServicing Your
Airbag-Equipped Vehicle on page 1-86.You should keep a record with all parts receipts and list
the mileage and the date of any service work you
perform. SeeMaintenance Record on page 6-17.
Adding Equipment to the Outside
of Your Vehicle
Things you might add to the outside of your vehicle
can affect the air ow around it. This may cause
wind noise and affect windshield washer performance.
Check with your dealer before adding equipment to
the outside of your vehicle.
Fuel
The 8th digit of your vehicle identi cation number (VIN)
shows the code letter or number that identi es your
engine. You will nd the VIN at the top left of the
instrument panel. SeeVehicle Identi cation Number
(VIN) on page 5-105.
If your vehicle has the 5.3L V8 engine (Code Z), you
may use either regular unleaded gasoline or ethanol
fuel containing up to 85% ethanol (E85); also see
Fuel E85 (85% Ethanol) on page 5-6. In all other
engines, use only regular unleaded gasoline.
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Gasoline Octane
Use regular unleaded gasoline with a posted octane
rating of 87 or higher. If the octane rating is less than 87,
you may notice an audible knocking noise when you
drive, commonly referred to as spark knock. If this
occurs, use a gasoline rated at 87 octane or higher
as soon as possible. If you are using gasoline rated
at 87 octane or higher and you hear heavy knocking,
your engine needs service.
Gasoline Speci cations
At a minimum, gasoline should meet ASTM
speci cation D 4814 in the United States or
CAN/CGSB-3.5 in Canada. Some gasolines may
contain an octane-enhancing additive called
methylcyclopentadienyl manganese tricarbonyl (MMT).
General Motors recommends against the use of
gasolines containing MMT. SeeAdditives on
page 5-5for additional information.
California Fuel
If your vehicle is certi ed to meet California Emissions
Standards, it is designed to operate on fuels that
meet California speci cations. See the underhood
emission control label. If this fuel is not available
in states adopting California emissions standards,
your vehicle will operate satisfactorily on fuels meeting
federal speci cations, but emission control system
performance may be affected. The malfunction
indicator lamp may turn on and your vehicle may fail
a smog-check test. SeeMalfunction Indicator Lamp
on page 3-46. If this occurs, return to your authorized
GM dealer for diagnosis. If it is determined that the
condition is caused by the type of fuel used, repairs
may not be covered by your warranty.
Additives
To provide cleaner air, all gasolines in the United
States are now required to contain additives that will
help prevent engine and fuel system deposits from
forming, allowing your emission control system to
work properly. In most cases, you should not have to
add anything to your fuel. However, some gasolines
contain only the minimum amount of additive required to
meet U.S. Environmental Protection Agency regulations.
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To help keep fuel injectors and intake valves clean,
or if your vehicle experiences problems due to
dirty injectors or valves, look for gasoline that is
advertised as TOP TIER Detergent Gasoline. Also,
your GM dealer has additives that will help correct
and prevent most deposit-related problems.
Gasolines containing oxygenates, such as ethers and
ethanol, and reformulated gasolines may be available in
your area. General Motors recommends that you use
these gasolines if they comply with the speci cations
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:Your vehicle was not designed for fuel
that contains methanol. Do not use fuel containing
methanol. It can corrode metal parts in your fuel
system and also damage the plastic and rubber
parts. That damage would not be covered under
your warranty.
Some gasolines that are not reformulated for low
emissions may contain an octane-enhancing additive
called methylcyclopentadienyl manganese tricarbonyl
(MMT); ask the attendant where you buy gasoline
whether the fuel contains MMT. General Motors
recommends against the use of such gasolines.Fuels containing MMT can reduce the life of spark plugs
and the performance of the emission control system
may be affected. The malfunction indicator lamp
may turn on. If this occurs, return to your authorized
GM dealer for service.
Fuel E85 (85% Ethanol)
The 8th digit of your vehicle identi cation number (VIN)
shows the code letter or number that identi es your
engine. You will nd the VIN at the top left of the
instrument panel. SeeVehicle Identi cation Number
(VIN) on page 5-105.
If your vehicle has the 5.3L V8 engine (VIN Code Z
only), you may use either regular unleaded gasoline
or ethanol fuel containing up to 85% ethanol (E85);
also seeFuel on page 5-4. In all other engines, including
the 5.3L V8 (VIN Code T), use only regular unleaded
gasoline.
Only vehicles that have the 5.3L V8 engine (VIN Code Z)
may use 85% ethanol fuel (E85). General Motors
encourages 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.
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Many service stations will not have an 85% ethanol
fuel (E85) pump available. The U. S. Department
of Energy has an alternative fuels website
(http://www.eere.energy.gov/ afdc/infrastructure/
locator.html) that can help you nd E85 fuel.
Those stations that do have E85 should have a
label indicating ethanol content. Do not use the fuel
if the ethanol content isgreaterthan 85%.
At a minimum, E85 should meet ASTM
Speci cation D 5798.
To ensure quick starts in the wintertime, the E85 fuel
must be formulated properly for your climate according
to ASTM speci cation D 5798. If you have trouble
starting on E85, it may be because your E85 fuel is
not properly formulated for your climate. If this happens,
switching to gasoline or adding gasoline to your fuel
tank may improve starting. Your vehicle is designed
to accommodate a mixture of gasoline and E85 fuel.
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.
E85 has less energy per gallon than gasoline, so
you will need to re ll your fuel tank more often when
using E85 than when you are using gasoline. Regular
unleaded gasoline is recommended when pulling
a trailer. For payload capacity with ethanol fuel,
seeLoading Your Vehicle on page 4-46.Notice:Some additives are not compatible with
E85 fuel and may harm your fuel system. Damage
caused by additives would not be covered by
your new vehicle warranty. Do not use additives
with E85 fuel.
Notice:Your vehicle was not designed for fuel
that contains methanol. Do not use fuel containing
methanol. It can corrode metal parts in your fuel
system and also damage the plastic and rubber
parts. That damage would not be covered under
your warranty.
Fuels in Foreign Countries
If you plan on driving in another country outside the
United States or Canada, the proper fuel may be hard
to nd. Never use leaded gasoline or any other fuel
not recommended in the previous text on fuel. Costly
repairs caused by use of improper fuel would not
be covered by your warranty.
To check the fuel availability, ask an auto club, or
contact a major oil company that does business in
the country where you will be driving.
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