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If the vehicle has the 5.3L V8 engine (VIN Code 4) and
the N15 flexible fuel option, you can use either regular
unleaded gasoline or ethanol fuel containing up to 85%
ethanol (E85). SeeFuel E85 (85% Ethanol) on page 5-8.
For the 5.3L V8 engine (VIN Code 4) without the N15
option and all other gasoline engines, use only regular
unleaded gasoline.
Gasoline Octane
Use regular unleaded gasoline with a posted octane
rating of 87 or higher. If the octane rating is less than 87,
you might 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,
the engine needs service.
Gasoline Speci cations
At 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 5-7
for additional information.
California Fuel
If 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 3-36. 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.
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To remove the fuel cap, turn it slowly counterclockwise.
While refueling, hang the tethered fuel cap from the
hook on the fuel door.
{CAUTION:
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 5-99.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 3-36.{CAUTION:
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 3-36.
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Calling for Assistance
When calling Roadside Assistance, have the following
information ready:
•Your name, home address, and home telephone
number
•Telephone number of your location
•Location of the vehicle
•Model, year, color, and license plate number of the
vehicle
•Odometer reading, Vehicle Identification
Number (VIN), and delivery date of the vehicle
•Description of the problem
Coverage
Services are provided up to 5 years/100,000 miles
(160 000 km), whichever comes first.
In the U.S., anyone driving the vehicle is covered.
In Canada, a person driving the vehicle without
permission from the owner is not covered.
Roadside Assistance is not a part of the New Vehicle
Limited Warranty. GMC and General Motors of Canada
Limited reserve the right to make any changes or
discontinue the Roadside Assistance program at any
time without notification.GMC and General Motors of Canada Limited reserve the
right to limit services or payment to an owner or driver if
they decide the claims are made too often, or the same
type of claim is made many times.
Services Provided
•Emergency Fuel Delivery:Delivery of enough fuel
for the vehicle to get to the nearest service station.
•Lock-Out Service:Service is provided to unlock the
vehicle if you are locked out. A remote unlock may be
available if you have OnStar
®. For security reasons,
the driver must present identification before this
service is given.
•Emergency Tow From a Public Road or Highway:
Tow to the nearest GMC dealer for warranty service,
or if the vehicle was in a crash and cannot be driven.
Assistance is also given when the vehicle is stuck in
the sand, mud, or snow.
•Flat Tire Change:Service is provided to change a
flat tire with the spare tire. The spare tire, if equipped,
must be in good condition and properly inflated.
It is the owner’s responsibility for the repair or
replacement of the tire if it is not covered by the
warranty.
•Battery Jump Start:Service is provided to jump
start a dead battery.
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