2003 GMC YUKON fuel

The fuel cap is located behind a hinged door on the
driver’s side of the vehicle.While refueling, hang the fuel cap by the tether using
the hook located on the inside of thefiller door.
To remove the fuel cap, turn it slowly to the left
(counterclockwise).
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2003 - Yukon/Yukon XL

{CAUTION:
If you get fuel on yourself 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. Clean fuel from painted
surfaces as soon as possible. SeeCleaning the Outside
of Your Vehicle on page 5-92.When you put the fuel cap back on, turn it to the right
(clockwise) until you hear a clicking sound. Make
sure you fully install the cap. 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.
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 nott properly.
This may cause your malfunction indicator lamp to
light and may damage your fuel tank and emissions
system. See“Malfunction Indicator Lamp”in the
Index.
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2003 - Yukon/Yukon XL

Filling a Portable Fuel Container
{CAUTION:
Neverll 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 notll a container while it is inside a
vehicle, in a vehicle’s trunk, pickup bed or
on any surface other than the ground.
Bring thell nozzle in contact with the
inside of thell opening before operating
the nozzle. Contact should be maintained
until thelling is complete.
Don’t smoke while pumping gasoline.
Checking Things Under
the Hood
{CAUTION:
If your vehicle has air conditioning, the
auxiliary electric fan under the hood can start
up even when the engine is not running and
can injure you. Keep hands, clothing and tools
away from any underhood electric fan.
{CAUTION:
Things that burn can get on hot engine parts
and start are. These include liquids like fuel,
oil, coolant, brakeuid, windshield washer and
otheruids, 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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2003 - Yukon/Yukon XL

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 3-64.
You should check your engine oil level regularly; this is
an added reminder.
Checking Engine Oil
It’s 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 has a yellow ring handle and is
located in the engine compartment on the passenger’s
side of the vehicle. SeeEngine Compartment Overview
on page 5-12for more information on location.
Turn off the engine and give the oil several minutes to
drain back into the oil pan. If you don’t, the oil
dipstick might not show the actual level.
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.
8.1L Engine
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2003 - Yukon/Yukon XL

As in the chart shown previously, SAE 5W-30 is the
only viscosity grade recommended for your vehicle. You
should look for and use only oils which have the API
Starburst symbol and which are also identified as
SAE 5W-30. If you cannotfind such SAE 5W-30 oils,
you can use an SAE 10W-30 oil which has the API
Starburst symbol, if it’s going to be 0°F(−18°C)
or above. Do not use other viscosity grade oils, such as
SAE 10W-40 or SAE 20W-50 under any conditions.
Notice:Use only engine oil with the American
Petroleum Institute Certied For Gasoline Engines
starburst symbol. Failure to use the recommended
oil can result in engine damage not covered by
your warranty.
GM Goodwrench
®oil meets all the requirements for
your vehicle.
If you are in an area of extreme cold, where the
temperature falls below−20°F(−29°C),itis
recommended that you use either an SAE 5W-30
synthetic oil or an SAE 0W-30 oil. Both will provide
easier cold starting and better protection for your engine
at extremely low temperatures.
Engine Oil Additives
Don’t add anything to your oil. The recommended oils
with the starburst symbol are all you will need for
good performance and engine protection.
When to Change Engine Oil (GM Oil
Life System)
Your vehicle has a computer system that lets you know
when to change the engine oil andfilter. This is based on
engine revolutions and engine temperature, and not on
mileage. Based on driving conditions, the mileage at
which an oil change will be indicated can vary
considerably. For the oil life system to work properly, you
must reset the system every time the oil is changed.
When the system has calculated that oil life has been
diminished, it will indicate that an oil change is necessary.
A CHANGE ENGINE OIL message will come on. Change
your oil as soon as possible within the next two times you
stop for fuel. It is possible that, if you are driving under the
best conditions, the oil life system may not indicate that
an oil change is necessary for over a year. However, your
engine oil andfilter must be changed at least once a year
and at this time the system must be reset. Your dealer
has GM-trained service people who will perform this work
using genuine GM parts and reset the system. It is also
important to check your oil regularly and keep it at the
proper level.
If the system is ever reset accidentally, you must
change your oil at 3,000 miles (5 000 km) since your
last oil change. Remember to reset the oil life system
whenever the oil is changed.
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2003 - Yukon/Yukon XL

6. Then replace the
pressure cap. Be sure
the pressure cap is
hand-tight and
fully seated.Engine Fan Noise
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.
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2003 - Yukon/Yukon XL

Ination -- Tire Pressure
The Certification/Tire label, which is on the rear edge of
the driver’s door, shows the correct inflation pressures
for your tires when they’re cold.“Cold”means your
vehicle has been sitting for at least three hours or driven
no more than 1 mile (1.6 km).
Notice:Don’t let anyone tell you that underination
or overination is all right. It’s not. If your tires
don’t have enough air (underination), you can get
the following:
Too muchexing
Too much heat
Tire overloading
Bad wear
Bad handling
Bad fuel economy
If your tires have too much air (overination), you
can get the following:
Unusual wear
Bad handling
Rough ride
Needless damage from road hazards
When to Check
Check your tires once a month or more.
Also, check the tire pressure of the spare tire.
How to Check
Use a good quality pocket-type gage to check tire
pressure. You can’t tell if your tires are properly inflated
simply by looking at them. Radial tires may look
properly inflated even when they’re underinflated.
Be sure to put the valve caps back on the valve stems.
They help prevent leaks by keeping out dirt and
moisture.
Tire Inspection and Rotation
Tires should be rotated every 7,500 miles (12 500 km).
Any time you notice unusual wear, rotate your tires
as soon as possible and check wheel alignment. Also
check for damaged tires or wheels. SeeWhen It Is Time
for New Tires on page 5-63andWheel Replacement
on page 5-66for more information.
Make sure the spare tire is stored securely. Push, pull,
and then try to rotate or turn the tire. If it moves,
use the ratchet/wheel wrench to tighten the cable. See
Changing a Flat Tire on page 5-69.
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2003 - Yukon/Yukon XL

Cleaning Tires
To clean your tires, use a stiff brush with tire cleaner.
Notice:When applying a tire dressing, always take
care to wipe off any overspray or splash from all
painted surfaces on the body or wheels of the
vehicle. Petroleum-based products may damage the
paintnish and tires.
Sheet Metal Damage
If your vehicle is damaged and requires sheet metal
repair or replacement, make sure the body repair shop
applies anti-corrosion material to parts repaired or
replaced to restore corrosion protection.
Original manufacturer replacement parts will provide the
corrosion protection while maintaining the warranty.
Finish Damage
Any stone chips, fractures or deep scratches in the
finish should be repaired right away. Bare metal
will corrode quickly and may develop into major repair
expense.
Minor chips and scratches can be repaired with touch-up
materials avaliable from your dealer. Larger areas of
finish damage can be corrected in your dealer’s
body and paint shop.
Underbody Maintenance
Chemicals used for ice and snow removal and dust
control can collect on the underbody. If these are not
removed, accelerated corrosion (rust) can occur on
the underbody parts such as fuel lines, frame,floor pan
and exhaust system even though they have corrosion
protection.
At least every spring,flush these materials from the
underbody with plain water. Clean any areas where mud
and debris can collect. Dirt packed in close areas of
the frame should be loosened before beingflushed.
Your dealer or an underbody car washing system can
do this for you.
Chemical Paint Spotting
Some weather and atmospheric conditions can create a
chemical fallout. Airborne pollutants can fall upon and
attack painted surfaces on your vehicle. This damage
can take two forms: blotchy, ringlet-shaped
discolorations, and small irregular dark spots etched into
the paint surface.
Although no defect in the paint job causes this, GM will
repair, at no charge to the owner, the surfaces of
new vehicles damaged by this fallout condition within
12 months or 12,000 miles (20 000 km) of purchase,
whichever occursfirst.
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2003 - Yukon/Yukon XL