CHECK OIL LEVEL
If the oil level in the vehicle is low, this message will
appear on the DIC. Check and oil level and correct it as
necessary. You may need to let the vehicle cool or
warm up and cycle the ignition to be sure this message
will clear. Once the problem is corrected, pressing
the select button will clear this message from the DIC
display.
CHECK WASHER FLUID
if the washerfluid level is low, this message will appear
on the DIC. Adding washerfluid will clear the message.
Pressing the select button will acknowledge this
message and clear it from the DIC display.
TRACTION ACTIVE
When the traction control system has detected that any
of the vehicle’s wheels are spinning, the traction
control system will activate and this message will appear
on the DIC. For more information seeTraction Assist
System (TAS) on page 4-10
TRANSMISSION HOT
If the transmissionfluid temperature becomes high, the
message center will display this message.
When the transmission enters the protection mode, you
may notice a change in the transmission shifting
patterns. When the transmissionfluid temperature
returns to normal, the display will turn off and the
transmission shifting patterns will return to normal.
Notice:If you keep driving your vehicle with the
transmission TRANS FLUID HOT message
displayed, you can damage the transmission. This
could lead to costly repairs that may not be covered
under your warranty.
The following situations can cause the transmission to
operate at higher temperatures:
•Towing a trailer
•Hot outside air temperatures
•Hauling a large or heavy load
•Low transmissionfluid level
•High transmissionfluid level
•Restricted airflow to the radiator and the auxiliary
transmission oil cooler.
3-68
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
Automatic Transmission Fluid
When to Check and Change
A good time to check your automatic transmissionfluid
level is when the engine oil is changed.
Change both thefluid andfilter every 50,000 miles
(83 000 km) if the vehicle’s GVWR is over 8,600 or if
the vehicle is mainly driven under one or more of these
conditions:
•In heavy city traffic where the outside temperature
regularly reaches 90°F (32°C) or higher.
•In hilly or mountainous terrain.
•When doing frequent trailer towing.
•Uses such as found in taxi, police or delivery
service.
If your vehicle’s GVWR is not over 8,600 and you do
not use your vehicle under any of these conditions,
change thefluid andfilter every 100,000 miles
(166 000 km).
SeePart A: Scheduled Maintenance Services on
page 6-4.
How to Check
Because this operation can be a little difficult, you may
choose to have this done at the dealership service
department.
If you do it yourself, be sure to follow all the instructions
here, or you could get a false reading on the dipstick.
Notice:Too much or too little uid can damage
your transmission. Too much can mean that some
of the uid could come out and fall on hot engine
part or exhaust system parts, starting a re.
Too little uid could cause the transmission to
overheat. Be sure to get an accurate reading if you
check your transmission uid.
Wait at least 30 minutes before checking the
transmissionfluid level if you have been driving:
•When outside temperatures are above 90°F (32°C).
•At high speed for quite a while.
•In heavy traffic–especially in hot weather.
•While pulling a trailer.
To get the right reading, thefluid should be at normal
operating temperature, which is 180°Fto200°F
(82°Cto93°C).
5-23
2003 - Yukon/Yukon XL
Get the vehicle warmed up by driving about 15 miles
(24 km) when outside temperatures are above 50°F
(10°C).Ifit’s colder than 50°F (10°C), drive the vehicle
in THIRD (3) until the engine temperature gage
moves and then remains steady for 10 minutes.
A coldfluid check can be made after the vehicle has
been sitting for eight hours or more with the engine off,
but this is used only as a reference. Let the engine
run at idle forfive minutes if outside temperatures are
50°F (10°C) or more. If it’s colder than 50°F (10°C), you
may have to idle the engine longer. Should thefluid
level be low during this cold check, youmustcheck the
fluid hot before addingfluid. Checking thefluid hot
will give you a more accurate reading of thefluid level.Checking the Fluid Level
Prepare your vehicle as follows:
•Park your vehicle on a level place. Keep the engine
running.
•With the parking brake applied, place the shift lever
in PARK (P).
•With your foot on the brake pedal, move the shift
lever through each gear range, pausing for about
three seconds in each range. Then, position the shift
lever in PARK (P).
•Let the engine run at idle for three minutes or more.
Then, without shutting off the engine, follow these
steps:
The transmission dipstick
handle with the graphic is
located at the rear of
the engine compartment,
on the passenger’s side.
5-24
2003 - Yukon/Yukon XL
SeeEngine Compartment Overview on page 5-12for
more information on location.
1. Flip the handle up and then pull out the dipstick
and wipe it with a clean rag or paper towel.
2. Push it back in all the way, wait three seconds and
then pull it back out again.
3. Check both sides of the dipstick, and read the lower
level. Thefluid level must be in the COLD area,
below the cross-hatched area, for a cold check or in
the HOT area or cross-hatched area for a hot
check.
4. If thefluid level is in the acceptable range, push the
dipstick back in all the way; thenflip the handle
down to lock the dipstick in place.How to Add Fluid
Refer to the Maintenance Schedule to determine what
kind of transmissionfluid to use. SeePart D:
Recommended Fluids and Lubricants on page 6-17.
Addfluid only after checking the transmissionfluid while
it is hot. (A cold check is used only as a reference.) If
thefluid level is low, add only enough of the properfluid
to bring the level up to the HOT area for a hot check.
It doesn’t take muchfluid, generally less than one
pint (0.5 L).Don’t overfill.
Notice:We recommend you use only uid labeled
DEXRON
®-III, because uid with that label is
made especially for your automatic transmission.
Damage caused by uid other than DEXRON
®-III is
not covered by your new vehicle warranty.
•After addingfluid, recheck thefluid level as
described underHow to Check.
•When the correctfluid level is obtained, push the
dipstick back in all the way; thenflip the handle
down to lock the dipstick in place.
5-25
2003 - Yukon/Yukon XL
At Least Twice a Year
Restraint System Check
Make sure the safety belt reminder light and all your
belts, buckles, latch plates, retractors and anchorages
are working properly. Look for any other loose or
damaged safety belt system parts. If you see anything
that might keep a safety belt system from doing its
job, have it repaired. Have any torn or frayed safety belts
replaced.
Also look for any opened or broken air bag coverings,
and have them repaired or replaced. (The air bag
system does not need regular maintenance.)
Wiper Blade Check
Inspect wiper blades for wear or cracking. Replace
blade inserts that appear worn or damaged or that
streak or miss areas of the windshield. Also see
Cleaning the Outside of Your Vehicle on page 5-92.
Spare Tire Check
At least twice a year, after the monthly in ation check of
the spare tire determines that the spare is in ated to
the correct tire in ation pressure, make sure that
the spare tire is stored securely. Push, pull, and then try
to rotate or turn the tire. If it moves, use the wheel
wrench/ratchet to tighten the cable. SeeChanging a Flat
Tire on page 5-69.
Weatherstrip Lubrication
Silicone grease on weatherstrips will make them last
longer, seal better, and not stick or squeak. Apply
silicone grease with a clean cloth. During very cold,
damp weather more frequent application may be
required. SeePart D: Recommended Fluids and
Lubricants on page 6-17.
Automatic Transmission Check
Check the transmission uid level; add if needed. See
Automatic Transmission Fluid on page 5-23.A uid loss
may indicate a problem. Check the system and repair
if needed.
At Least Once a Year
Key Lock Cylinders Service
Lubricate the key lock cylinders with the lubricant
speci ed in Part D.
Body Lubrication Service
Lubricate all hood latch assembly, secondary latch,
pivots, spring anchor, release pawl, rear compartment
hinges, outer liftgate handle pivot points, rear door
detent link, roller mechanism, liftgate handle pivot points,
latch bolt, fuel door hinge, cargo door hinge, locks
and folding seat hardware. Part D tells you what to use.
More frequent lubrication may be required when
exposed to a corrosive environment.
6-12
2003 - Yukon/Yukon XL
Audio System(s) (cont.)
Setting the Time for Radios with Radio Data
Systems (RDS)........................................3-72
Setting the Time for Radios without Radio
Data Systems (RDS)................................3-71
Theft-Deterrent Feature...............................3-122
Understanding Radio Reception...................3-123
XM™Satellite Radio Antenna System...........3-126
Automatic Headlamp System............................3-15
Automatic Level Control...................................4-60
Automatic Transfer Case..................................2-26
Automatic Transmission
Fluid..........................................................5-23
Operation...................................................2-22
Automatic Transmission Check..........................6-12
Automatic Transmission Shift Lock Control
System Check.............................................6-13
Autoride™.....................................................4-60
Auxiliary Roof Mounted Lamp Switch.................3-17
B
Backing Up....................................................4-69
Battery..........................................................5-43
BATTERY NOT CHARGING.............................3-65
Battery Replacement......................................... 2-6
Battery Run-Down Protection............................3-20
Battery Warning Light......................................3-42
Before Leaving on a Long Trip.........................4-44
Before You Drive...........................................3-111Before You Go Off-Roading..............................4-25
Bench Seat....................................................1-15
Bench Seat Split (50/50)..................................1-11
Bench Seat, Split (60/40)................................... 1-9
Body Lubrication Service..................................6-12
Brake
Parking......................................................2-34
System Inspection.......................................6-16
System Warning Light..................................3-43
Brake Adjustment............................................5-43
Brake Fluid
....................................................5-40
Brake Pedal, Throttle
.......................................2-21
Brake Pedal Travel
.........................................5-43
Brake Wear
...................................................5-42
Brakes
..........................................................5-40
Braking
........................................................... 4-6
Braking in Emergencies
..................................... 4-9
Break-In, New Vehicle
.....................................2-18
Bucket Seats, Rear
.........................................1-20
Bulb Replacement
...........................................5-52
Front Turn Signal, Sidemarker and Daytime
Running Lamps
........................................5-54
Halogen Bulbs
............................................5-53
Headlamps
.................................................5-53
Replacement Bulbs
......................................5-59
Roof Marker Lamps
.....................................5-55
Side Identification Marker Lamps
...................5-55
Taillamps
....................................................5-57
Buying New Tires
...........................................5-64
2
2003 - Yukon/Yukon XL
H
Hazard Warning Flashers................................... 3-6
Head Restraints............................................... 1-8
Headlamp High/Low-Beam Changer.................... 3-9
Headlamps....................................................5-53
Bulb Replacement.......................................5-52
Front Turn Signal, Sidemarker and Daytime
Running Lamps........................................5-54
Halogen Bulbs............................................5-53
Roof Marker Lamps.....................................5-55
Side Identification Marker Lamps...................5-55
Headphones.................................................3-117
Heated Seats................................................... 1-5
Heating.........................................................3-30
Highway Hypnosis...........................................4-44
Hill and Mountain Roads..................................4-45
Hitches..........................................................4-67
HomeLink Transmitter, Programming..................2-51
HomeLink
®Transmitter....................................2-50
Hood
Checking Things Under................................5-10
Release.....................................................5-11
Horn ............................................................... 3-7
How to Add Coolant to the Coolant Surge Tank......5-34
How to Add Fluid
............................................5-25
How to Check
........................................5-23, 5-61
How to Check Lubricant
...................................5-50How to Check Power Steering Fluid..................5-39
How to Inspect...............................................5-21
How to Use This Manual...................................... ii
How to Wear Safety Belts Properly...................1-27
Hydroplaning..................................................4-40
I
If No Steam Is Coming From Your Engine..........5-31
If Steam Is Coming From Your Engine...............5-30
If the Light is Flashing.....................................3-49
If the Light Is On Steady.................................3-49
If You Are Stuck in Sand, Mud, Ice or Snow.......4-52
If You Do Decide To Pull A Trailer.....................4-62
If You’re Caught in a Blizzard...........................4-50
Ignition Positions.............................................2-19
Ignition Transmission Lock Check......................6-14
Infants and Young Children, Restraints...............1-46
Inflation -- Tire Pressure..................................5-61
Inspection
Brake System.............................................6-16
Engine Cooling System................................6-16
Exhaust System..........................................6-15
Fuel System...............................................6-15
Part C - Periodic Maintenance.......................6-15
Steering and Suspension..............................6-15
Transfer Case and Front Axle
(Four-Wheel Drive)...................................6-16
8
2003 - Yukon/Yukon XL