2005 GMC YUKON fuel

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. General
Motors recommends that you buy gasolines that are
advertised to help keep fuel injectors and intake valves
clean. If your vehicle experiences problems due to dirty
injectors or valves, try a different brand of 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 to contribute to clean air. General Motors
recommends that you use these gasolines, particularly if
they comply with the specications described earlier.
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
does not recommend 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 E-85 (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 5-104.
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 (E-85); also seeFuel
on page 5-5. In all other engines, including the 5.3L V8
(VIN Code T), use only regular unleaded gasoline.
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Only vehicles that have the 5.3L V8 engine (VIN Code Z)
may use 85% ethanol fuel (E-85). General Motors
encourages the use of E-85 in vehicles that are designed
to use it. The ethanol in E-85 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 (E-85) pump available. The U. S. Department
of Energy has an alternative fuels website
(http://www.afdc.doe.gov/refueling_mapsite.shtml) that
can help you nd E-85 fuel. Those stations that do have
E-85 should have a label indicating ethanol content.
Do not use the fuel if the ethanol content isgreaterthan
85%. Your vehicle may not operate properly if the
ethanol content is greater than 85%.
At a minimum, E-85 should meet ASTM
Specication D 5798.
To ensure quick starts in the wintertime, the E-85 fuel
must be formulated properly for your climate according
to ASTM specication D 5798. If you have trouble
starting on E-85, it may be because your E-85 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 E-85 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.E-85 has less energy per gallon than gasoline, so you
will need to rell your fuel tank more often when
using E-85 than when you are using gasoline. Regular
unleaded gasoline is recommended when pulling a
trailer. For payload capacity with ethanol fuel, see
Loading Your Vehicle on page 4-51.
Notice:Some additives are not compatible with
E-85 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 E-85 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.
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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.
The tethered fuel cap is located behind a hinged fuel
door on the driver’s side of the vehicle.
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.
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{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.
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. See
Washing Your Vehicle on page 5-99.
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 3-48.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 3-58for 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. SeeMalfunction Indicator Lamp on
page 3-48.
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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.
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.
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.
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A. Engine Air Cleaner/Filter. SeeEngine Air
Cleaner/Filter on page 5-19.
B. Coolant Surge Tank and Pressure Cap. SeeCooling
System on page 5-29andCoolant Surge Tank
Pressure Cap on page 5-26.
C. Air Filter Restriction Indicator (If Equipped). See
Engine Air Cleaner/Filter on page 5-19.
D. Engine Oil Dipstick. See “Checking Engine Oil”
underEngine Oil on page 5-15.
E. Automatic Transmission Dipstick. See “Checking the
Fluid Level” underAutomatic Transmission Fluid
on page 5-21.
F. Engine Oil Fill Cap. See “When to Add Engine Oil”
underEngine Oil on page 5-15.
G. Engine Cooling Fan. SeeCooling System on
page 5-29.
H. Remote Negative (−) Terminal (GND). SeeJump
Starting on page 5-41.
I. Remote Positive (+) Terminal. SeeJump Starting on
page 5-41.
J. Power Steering Fluid Reservoir. SeePower Steering
Fluid on page 5-35.
K. Brake Master Fluid Reservoir. See “Brake Fluid”
underBrakes on page 5-37.
L. Underhood Fuse Block. SeeUnderhood Fuse Block
on page 5-109.M. Battery. SeeBattery on page 5-40.
N. Windshield Washer Fluid Reservoir. See “Adding
Washer Fluid” underWindshield Washer Fluid
on page 5-36.
Engine Oil
If the CHECK OIL LEVEL message appears on the
instrument cluster, it means you need to check
your engine oil level right away.
For more information, see CHECK OIL LEVEL under
DIC Warnings and Messages on page 3-58.
You should check your engine oil level regularly; this is
an added reminder.
Checking Engine Oil
It is a good idea to check your 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. See
Engine Compartment Overview on page 5-12for
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.
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4. With the coolant surge tank pressure cap off, start
the engine and let it run until you can feel the upper
radiator hose getting hot. Watch out for the
engine cooling fan.
By this time, the coolant level inside the coolant
surge tank may be lower. If the level is lower, add
more of the proper mixture to the coolant surge tank
until the level reaches the FULL COLD mark.
5. Then replace the pressure cap. Be sure the
pressure cap is hand-tight and fully seated.
Engine Fan Noise
If your vehicle is equipped with 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 is equipped with 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 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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Tire Terminology and Denitions
Air Pressure:The amount of air inside the tire pressing
outward on each square inch of the tire. Air pressure
is expressed in pounds per square inch (psi) or
kilopascal (kPa).
Accessory Weight:This means the combined weight
of optional accessories. Some examples of optional
accessories are, automatic transmission, power steering,
power brakes, power windows, power seats, and air
conditioning.
Aspect Ratio:The relationship of a tire’s height to its
width.
Belt:A rubber coated layer of cords that is located
between the plies and the tread. Cords may be made
from steel or other reinforcing materials.
Bead:The tire bead contains steel wires wrapped by
steel cords that hold the tire onto the rim.
Bias Ply Tire:A pneumatic tire in which the plies are
laid at alternate angles less than 90 degrees to the
centerline of the tread.Cold Ination Pressure:The amount of air pressure in
a tire, measured in pounds per square inch (psi) or
kilopascals (kPa) before a tire has built up heat
from driving. SeeInation - Tire Pressure on page 5-64.
Curb Weight:This means the weight of a motor
vehicle with standard and optional equipment including
the maximum capacity of fuel, oil and coolant, but
without passengers and cargo.
DOT Markings:A code molded into the sidewall of a
tire signifying that the tire is in compliance with the U.S.
Department of Transportation (DOT) motor vehicle
safety standards. The DOT code includes the Tire
Identication Number (TIN), an alphanumeric designator
which can also identify the tire manufacturer, production
plant, brand and date of production.
GVWR:Gross Vehicle Weight Rating, seeLoading
Your Vehicle on page 4-51.
GAWR FRT:Gross Axle Weight Rating for the front
axle, seeLoading Your Vehicle on page 4-51.
GAWR RR:Gross Axle Weight Rating for the rear axle,
seeLoading Your Vehicle on page 4-51.
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