2007 GMC SIERRA CLASSIC fuel

Fuel E85 (85% Ethanol)
The 8th digit of your Vehicle Identication Number
(VIN) shows the code letter or number that
identies your engine. You will nd the VIN at
the top left of the instrument panel. SeeVehicle
Identication Number (VIN) on page 598.
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 470.
In all other engines, use only the unleaded
gasoline described underGasoline Octane on
page 470.
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.
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 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 is greater than 85%.
At a minimum, E85 should meet ASTM
Specication D 5798.
To ensure quick starts in the wintertime, the
E85 fuel must be formulated properly for your
climate according to ASTM specication 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. 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 ve gallons
(18.9 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.
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E85 has less energy per gallon than gasoline, so
you will need to rell your fuel tank more often
when using E85 than when you are using gasoline.
SeeFilling the Tank on page 474.
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.
Filling the Tank
{CAUTION:
Fuel vapor burns violently and a fuel re
can cause bad injuries. To help avoid
injuries to you and others, read and follow
all the instructions on the pump island.
Turn off your engine when you are
refueling. Do not smoke if you are near
fuel or refueling your vehicle. Keep
sparks, ames, and smoking materials
away from fuel. Do not leave the fuel
pump unattended when refueling your
vehicle. This is against the law in some
places. Keep children away from the fuel
pump; never let children pump fuel.
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The tethered fuel cap is located behind a hinged
fuel door on the driver’s side of the vehicle. If
the vehicle has E85 fuel capability, a yellow cap
with the words″E85 or gasoline″can be seen.
To remove the fuel cap, turn it slowly
counterclockwise. It will require more effort
to turn the fuel cap on the last turn as you
loosen it.
{CAUTION:
If you spill fuel and then something
ignites it, you could be badly burned. Fuel
can spray out on you if you open the fuel
cap too quickly. This spray can happen if
your 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.
If your vehicle is a dual fuel tank chassis cab
model, and it runs out of fuel, refuel the front fuel
tank rst to ensure a quick restart.
Be careful not to spill fuel. Do not top off or overll
the tank and wait a few seconds after you have
nished pumping before removing the nozzle.
Clean fuel from painted surfaces as soon as
possible. SeeWashing Your Vehicle on page 592.
475

When replacing the fuel cap, turn it clockwise until it
clicks. It will require more effort to turn the fuel cap
on the last turn as you tighten it. 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 258.
The TIGHTEN FUEL CAP message will be
displayed on the Driver Information Center (DIC) if
the fuel cap is not properly installed. SeeDIC
Warnings and Messages on page 270for more
information.
{CAUTION:
If a re starts while you are refueling, do
not remove the nozzle. Shut off the ow
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 can get one
for you. If you get the wrong type, it may not
t properly. This may cause your malfunction
indicator lamp to light and may damage
your fuel tank and emissions system. See
Malfunction Indicator Lamp on page 258.
476

Filling a Portable Fuel Container
{CAUTION:
Never ll a portable fuel container while
it is in your vehicle. Static electricity
discharge from the container can ignite
the gasoline vapor. You can be badly
burned and your vehicle damaged if this
occurs. To help avoid injury to you and
others:
Dispense gasoline only into approved
containers.
Do not ll a container while it is inside
a vehicle, in a vehicle’s trunk, pickup
bed, or on any surface other than the
ground.
CAUTION: (Continued)
CAUTION: (Continued)

Bring the ll nozzle in contact with
the inside of the ll opening before
operating the nozzle. Contact should
be maintained until the lling is
complete.
Do not smoke while pumping
gasoline.
477

Checking Things Under
the Hood
{CAUTION:
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.
{CAUTION:
Things that burn can get on hot engine
parts and start a re. These include
liquids like fuel, oil, coolant, brake uid,
windshield washer and other uids, 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.
478

Engine Oil (Gasoline Engine)
If your vehicle has a diesel engine, see “Engine
Oil” in the DURAMAX®Diesel Engine Supplement.
If the CHECK OIL LEVEL light appears on the
instrument cluster, except vehicles that have the
4.3L engine, it means you need to check the
engine oil level right away.
For more information, seeDriver Information
Center (DIC) on page 265. You should check
your engine oil level regularly; this is an added
reminder.
Checking Engine Oil
It is a good idea to check the engine oil every time
you get fuel. 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 480
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 you
do not do this, 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.
486

Engine Fan Noise
If your vehicle has a clutched engine cooling fan,
when the clutch is engaged, the fan spins
faster to provide more air to cool the engine. In
most everyday driving conditions, the fan is
spinning slower and the clutch is not fully engaged.
This improves fuel economy and reduces fan
noise. Under heavy vehicle loading, trailer towing,
and/or high outside temperatures, the fan speed
increases as the clutch more fully engages, so
you may hear an increase in fan noise. This
is normal and should not be mistaken as the
transmission slipping or making extra shifts. It is
merely the cooling system functioning properly.
The fan will slow down when additional cooling is
not required and the clutch disengages.
You may also hear this fan noise when you start
the engine. It will go away as the fan clutch
partially disengages.If your vehicle has electric cooling fans, you may
hear the fans spinning at low speed during
most everyday driving. The fans may turn off if no
cooling is required. Under heavy vehicle loading,
trailer towing, and/or high outside temperatures, or
if you are operating your air conditioning system,
the fans may change to high speed and you
may hear an increase in fan noise. This is
normal and indicates that the cooling system is
functioning properly. The fans will change to
low speed when additional cooling is no longer
required.
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