2003 GMC YUKON fuel cap

Seats and Restraint Systems........................... 1-3
Front Seats
............................................... 1-3
Rear Seats
............................................... 1-8
Safety Belts
.............................................1-22
Child Restraints
.......................................1-44
Air Bag Systems
......................................1-70
Restraint System Check
............................1-86
Features and Controls..................................... 2-1
Keys
........................................................ 2-3
Doors and Locks
....................................... 2-7
Windows
.................................................2-14
Theft-Deterrent Systems
............................2-16
Starting and Operating Your Vehicle
...........2-18
Mirrors
....................................................2-40
OnStar
®System
......................................2-48
HomeLink®Transmitter
.............................2-50
Storage Areas
.........................................2-54
Sunroof
..................................................2-57
Vehicle Personalization
.............................2-58
Instrument Panel............................................. 3-1
Instrument Panel Overview
.......................... 3-4
Climate Controls
......................................3-21
Warning Lights, Gages and Indicators
.........3-37
Driver Information Center (DIC)
..................3-53
Audio System(s)
.......................................3-71Driving Your Vehicle....................................... 4-1
Your Driving, the Road, and Your Vehicle
..... 4-2
Towing
...................................................4-54
Service and Appearance Care.......................... 5-1
Service
..................................................... 5-3
Fuel
......................................................... 5-4
Checking Things Under the Hood
...............5-10
All-Wheel Drive
........................................5-49
Rear Axle
...............................................5-50
Four-Wheel Drive
.....................................5-51
Front Axle
...............................................5-52
Bulb Replacement
....................................5-52
Windshield Wiper Blade Replacement
.........5-59
Tires
......................................................5-60
Appearance Care
.....................................5-88
Vehicle Identication
.................................5-96
Electrical System
......................................5-97
Capacities and Specications
...................5-106
Normal Maintenance Replacement Parts
....5-109
Maintenance Schedule..................................... 6-1
Maintenance Schedule
................................ 6-2
Customer Assistance Information.................... 7-1
Customer Assistance Information
.................. 7-2
Reporting Safety Defects
............................ 7-9
Index................................................................ 1
2003 GMC Yukon/Yukon XLM
2003 - Yukon/Yukon XL

If the Light is Flashing
The following may prevent more serious damage to
your vehicle:
•Reducing vehicle speed.
•Avoiding hard accelerations.
•Avoiding steep uphill grades.
•If you are towing a trailer, reduce the amount of
cargo being hauled as soon as it is possible.
If the light stopsflashing and remains on steady, see“If
the Light Is On Steady”following.
If the light continues toflash, when it is safe to do so,
stop the vehicle.Find a safe place to park your vehicle.
Turn the key off, wait at least 10 seconds and restart
the engine. If the light remains on steady, see“If
the Light Is On Steady”following. If the light is still
flashing, follow the previous steps, and see your dealer
for service as soon as possible.
If the Light Is On Steady
You may be able to correct the emission system
malfunction by considering the following:
Did you recently put fuel into your vehicle?
If so, reinstall the fuel cap, making sure to fully install
the cap. SeeFilling Your Tank on page 5-7. The
diagnostic system can determine if the fuel cap has
been left off or improperly installed. A loose or missing
fuel cap will allow fuel to evaporate into the atmosphere.
A few driving trips with the cap properly installed
should turn the light off.
Did you just drive through a deep puddle of water?
If so, your electrical system may be wet. The condition
will usually be corrected when the electrical system
dries out. A few driving trips should turn the light off.
3-49
2003 - Yukon/Yukon XL

Here are some situations you may experience with your
fuel gage. None of these indicate a problem with the
fuel gage.
•At the gas station, the fuel pump shuts off before
the gage reads full.
•It takes a little more or less fuel tofill up than the
fuel gage indicated. For example, the gage may
have indicated the tank was half full, but it actually
took a little more or less than half the tank’s
capacity tofill the tank.
•The gage goes back to empty when you turn off the
ignition.
Low Fuel Warning Light
The light next to the fuel gage will come on briefly when
you are starting the engine.
This light comes on when the fuel tank is low on fuel.
To turn it off, add fuel to the fuel tank. SeeFuel on
page 5-4.
Driver Information Center (DIC)
The DIC display is located on the instrument panel
cluster above the steering wheel. The DIC can display
information such as the trip odometer, fuel economy and
personalization features.
A (Trip Information):This button will display the
odometer, personal trip odometer, business trip
odometer, hourmeter, annual log and the timer.
B (Fuel Information):This button will display the
current range, average fuel economy, instant fuel
economy and engine oil life.
3-53
2003 - Yukon/Yukon XL

Loading Your Vehicle
The Certication/Tire label is found on the rear edge of
the driver’s door or in the Incomplete Vehicle
Document in the cab.
The label shows the size of your original tires and the
ination pressures needed to obtain the gross weight
capacity of your vehicle. This is called the GVWR (Gross
Vehicle Weight Rating). The GVWR includes the
weight of the vehicle, all occupants, fuel and cargo.
The Certication/Tire label also tells you the maximum
weights for the front and rear axles, called Gross
Axle Weight Rating (GAWR). Tond out the actual loadson your front and rear axles, you need to go to a weigh
station and weigh your vehicle. Your dealer can help
you with this. Be sure to spread out your load equally on
both sides of the centerline.
Never exceed the GVWR for your vehicle, or the GAWR
for either the front or rear axle.
The Certication/Tire label also contains information
about your Front Axle Reserve Capacity. See“Front
Axle Reserve Capacity”later in this section.
And, if you do have a heavy load, you should spread
it out.
{CAUTION:
Do not load your vehicle any heavier than the
GVWR, or either the maximum front or rear
GAWR. If you do, parts on your vehicle can
break, and it can change the way your vehicle
handles. These could cause you to lose
control and crash. Also, overloading can
shorten the life of your vehicle.
Notice:Your warranty does not cover parts or
components that fail because of overloading.
The label will help you decide how much cargo and
installed equipment your truck can carry.
4-58
2003 - Yukon/Yukon XL

You’ll get the best performance if you spread out the
weight of your load the right way, and if you choose the
correct hitch and trailer brakes.
For more information, seeTowing a Trailer on page 4-61
Towing a Trailer.
Towing a Trailer
{CAUTION:
If you don’t use the correct equipment and
drive properly, you can lose control when you
pull a trailer. For example, if the trailer is too
heavy, the brakes may not work well -- or even
at all. You and your passengers could be
seriously injured. Pull a trailer only if you have
followed all the steps in this section. Ask your
dealer for advice and information about towing
a trailer with your vehicle.Notice:Pulling a trailer improperly can damage
your vehicle and result in costly repairs not covered
by your warranty. To pull a trailer correctly, follow
the advice in this part, and see your dealer for
important information about towing a trailer with
your vehicle.
To identify the vehicle trailering capacity of your vehicle,
you should read the information in“Weight of the
Trailer”that appears later in this section.
If yours was built with trailering options, as many are,
it’s ready for heavier trailers. But trailering is different
than just driving your vehicle by itself. Trailering means
changes in handling, durability and fuel economy.
Successful, safe trailering takes correct equipment, and
it has to be used properly.
That’s the reason for this part. In it are many time-tested,
important trailering tips and safety rules. Many of
these are important for your safety and that of your
passengers. So please read this section carefully before
you pull a trailer.
4-61
2003 - Yukon/Yukon XL

Service............................................................5-3
Doing Your Own Service Work.........................5-3
Adding Equipment to the Outside of Your
Vehicle......................................................5-4
Fuel................................................................5-4
Gasoline Octane............................................5-4
Gasoline Specifications....................................5-4
California Fuel...............................................5-5
Additives.......................................................5-5
Fuel E-85 (85% Ethanol).................................5-6
Fuels in Foreign Countries...............................5-7
Filling Your Tank............................................5-7
Filling a Portable Fuel Container.....................5-10
Checking Things Under
the Hood....................................................5-10
Hood Release..............................................5-11
Engine Compartment Overview.......................5-12
Engine Oil...................................................5-16
Engine Air Cleaner/Filter................................5-21
Automatic Transmission Fluid.........................5-23
Engine Coolant.............................................5-26
Coolant Surge Tank Pressure Cap..................5-29Engine Overheating.......................................5-29
Cooling System............................................5-32
Engine Fan Noise.........................................5-37
Power Steering Fluid.....................................5-38
Windshield Washer Fluid................................5-39
Brakes........................................................5-40
Battery........................................................5-43
Jump Starting...............................................5-44
All-Wheel Drive..............................................5-49
Rear Axle.......................................................5-50
Four-Wheel Drive............................................5-51
Front Axle......................................................5-52
Bulb Replacement..........................................5-52
Halogen Bulbs..............................................5-53
Headlamps..................................................5-53
Front Turn Signal, Sidemarker and Daytime
Running Lamps.........................................5-54
Side Identification Marker Lamps.....................5-55
Roof Marker Lamps......................................5-55
Taillamps.....................................................5-57
Replacement Bulbs
.......................................5-59
Section 5 Service and Appearance Care
5-1
2003 - Yukon/Yukon XL

E-85 has less energy per gallon than gasoline, so you’ll
need to refill your fuel tank more often when using
E-85 than when you’re using gasoline. Regular unleaded
gasoline is recommended when pulling a trailer. For
payload capacity with ethanol fuel, seeLoading
Your Vehicle on page 4-58.
Notice:Some additives are not compatible with
E-85 fuel and may harm your fuel system. Damage
caused by additives wouldn’t be covered by
your new vehicle warranty. Don’t use additives with
E-85 fuel.
Notice:Your vehicle was not designed for fuel that
contains methanol. Don’t use fuel containing
methanol. It can corrode metal parts in your fuel
system and also damage the plastic and rubber
parts. That damage wouldn’t 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
tofind. Never use leaded gasoline or any other fuel
not recommended in the previous text on fuel. Costly
repairs caused by use of improper fuel wouldn’tbe
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’ll be driving.
Filling Your Tank
{CAUTION:
Fuel vapor is highly ammable. It burns
violently, and that can cause very bad injuries.
Don’t smoke if you’re near fuel or refueling
your vehicle. Keep sparks, ames and smoking
materials away from fuel.
5-7
2003 - Yukon/Yukon XL

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).
5-8
2003 - Yukon/Yukon XL