2003 GMC YUKON Maintenance

Properly torqued wheel nuts are necessary to help
prevent brake pulsation. When tires are rotated, inspect
brake pads for wear and evenly tighten wheel nuts in
the proper sequence to GM torque specifications.
Brake linings should always be replaced as complete
axle sets.
SeeBrake System Inspection on page 6-16.
Brake Pedal Travel
See your dealer if the brake pedal does not return to
normal height, or if there is a rapid increase in
pedal travel. This could be a sign of brake trouble.
Brake Adjustment
Every time you make a brake stop, your disc brakes
adjust for wear.
Replacing Brake System Parts
The braking system on a vehicle is complex. Its many
parts have to be of top quality and work well together if
the vehicle is to have really good braking. Your
vehicle was designed and tested with top-quality GM
brake parts. When you replace parts of your brakingsystem–for example, when your brake linings wear
down and you need new ones put in–be sure you get
new approved GM replacement parts. If you don’t,
your brakes may no longer work properly. For example,
if someone puts in brake linings that are wrong for
your vehicle, the balance between your front and rear
brakes can change—for the worse. The braking
performance you’ve come to expect can change in many
other ways if someone puts in the wrong replacement
brake parts.
Battery
Your new vehicle comes with a maintenance free
ACDelco®battery. When it’s time for a new battery, get
one that has the replacement number shown on the
original battery’s label. We recommend an ACDelco
®
battery. SeeEngine Compartment Overview on
page 5-12for battery location.
Warning:Battery posts, terminals and related
accessories contain lead and lead compounds,
chemicals known to the State of California to cause
cancer and reproductive harm. Wash hands after
handling.
5-43
2003 - Yukon/Yukon XL

To disconnect the jumper cables from both vehicles do
the following:
1. Disconnect the black negative (−) cable from the
vehicle that had the bad battery.
2. Disconnect the black negative (−) cable from
vehicle with the good battery.
3. Disconnect the red positive (+) cable from the
vehicle with the good battery.
4. Disconnect the red positive (+) cable from the other
vehicle.
5. Return the positive (+) remote terminal cover to its
original position.
All-Wheel Drive
Lubricant checks in this section also apply to these
vehicles. However, there are two additional systems that
need lubrication.
Transfer Case
When to Check Lubricant
Refer to the Maintenance Schedule to determine how
often to check the lubricant. SeePart C: Periodic
Maintenance Inspections on page 6-15.
How to Check Lubricant
To get an accurate reading, the vehicle should be on a
level surface.Automatic Transfer Case (A) Fill Plug (B) Drain Plug
5-49
2003 - Yukon/Yukon XL

If the level is below the bottom of thefiller plug hole,
you’ll need to add some lubricant. Add enough lubricant
to raise the level to the bottom of thefiller plug hole.
Use care not to overtighten the plug.
What to Use
Refer to the Maintenance Schedule to determine what
kind of lubricant to use. SeePart D: Recommended
Fluids and Lubricants on page 6-17.
Rear Axle
When to Check Lubricant
Refer to the Maintenance Schedule to determine how
often to check the lubricant. See Part A:Part A:
Scheduled Maintenance Services on page 6-4.
How to Check Lubricant
To get an accurate reading, the vehicle should be on a
level surface.
The proper level for the 1500 Series is from 5/8 inch to
1 5/8 inch (15 mm to 40 mm) below the bottom of thefiller
plug hole. The proper level for the 2500 Series is from
0 to 1/2 inch (0 to 13 mm) below the bottom of thefiller
plug hole. The proper level for the 1500 and 2500 series
vehicles with QUADRASTEER™(4 Wheel Steer) is from
0 to 1/4 inch (0 to 6 mm) below thefiller plug hole. Add
only enoughfluid to reach the proper level. 1500 Series shown, 2500 similar
5-50
2003 - Yukon/Yukon XL

What to Use
Refer to the Maintenance Schedule to determine what
kind of lubricant to use. See Part D:Part D:
Recommended Fluids and Lubricants on page 6-17.
Four-Wheel Drive
Lubricant checks in this section also apply to these
vehicles. However, there are two additional systems that
need lubrication.
Transfer Case
When to Check Lubricant
Refer to the Maintenance Schedule to determine how
often to check the lubricant. SeePart C: Periodic
Maintenance Inspections on page 6-15.
How to Check Lubricant
To get an accurate reading, the vehicle should be on a
level surface.
If the level is below the bottom of thefiller plug hole,
you’ll need to add some lubricant. Add enough lubricant
to raise the level to the bottom of thefiller plug hole.
Use care not to overtighten the plug.
What to Use
Refer to the Maintenance Schedule to determine what
kind of lubricant to use. SeePart D: Recommended
Fluids and Lubricants on page 6-17. Automatic Transfer Case
5-51
2003 - Yukon/Yukon XL

Front Axle
When to Check Lubricant
Refer to the Maintenance Schedule to determine how
often to check the lubricant. See Part A:Part A:
Scheduled Maintenance Services on page 6-4.
How to Check Lubricant
To get an accurate reading, the vehicle should be on a
level surface.If the level is below the bottom of thefiller plug hole,
you may need to add some lubricant.
When the differential is cold, add enough lubricant to
raise the level to 0 to 3/8 inch (9.5 mm) below thefiller
plug hole.
When the differential is at operating temperature
(warm), add enough lubricant to raise the level to the
bottom of thefiller plug hole.
What to Use
Refer to the Maintenance Schedule to determine what
kind of lubricant to use. See Part D:Part D:
Recommended Fluids and Lubricants on page 6-17.
Bulb Replacement
For any bulb changing procedure not listed in this
section, contact your dealer.
SeeReplacement Bulbs on page 5-59for the proper
types of bulbs to use.
5-52
2003 - Yukon/Yukon XL

Replacement Bulbs
Exterior Lamp Bulb Number
Low-Beam Headlamps 9006
High-Beam Headlamps 9005
Daytime Running Lamps (DRL 4114K
Front Roof Marker Lamp 194
Front Parking and Turn Lamp 3457A
Rear Marker Lamp, Taillamp and
Stop Lamp3157
Rear Turn Lamp 3157
Back-up Lamp 3157
For any bulb not listed here contact your dealer.
Windshield Wiper Blade
Replacement
Windshield wiper blades should be inspected at least
twice a year for wear and cracking. SeeAt Least Twice
a Year on page 6-12for more information.
Replacement blades come in different types and are
removed in different ways. For proper type and length,
seeNormal Maintenance Replacement Parts on
page 5-109.To replace the windshield wiper blade assembly do the
following:
1. Lift the wiper arm and turn the blade until it is
facing away from the windshield.
2. Push the release lever and slide the wiper assembly
toward the driver’s side of the vehicle.
3. Install a new blade by reversing Steps 1 and 2.
5-59
2003 - Yukon/Yukon XL

The purpose of regular rotation is to achieve more
uniform wear for all tires on the vehicle. Thefirst rotation
is the most important. See“Part A: Scheduled
Maintenance Services,”in Section 6, for scheduled
rotation intervals.
When rotating your tires, always use the correct rotation
pattern shown here.
After the tires have been rotated, adjust the front and
rear inflation pressures as shown on the
Certification/Tire label. Make certain that all wheel nuts
are properly tightened. See“Wheel Nut Torque”
underCapacities and Specifications on page 5-106.
{CAUTION:
Rust or dirt on a wheel, or on the parts to
which it is fastened, can make wheel nuts
become loose after a time. The wheel could
come off and cause an accident. When you
change a wheel, remove any rust or dirt from
places where the wheel attaches to the vehicle.
In an emergency, you can use a cloth or a
paper towel to do this; but be sure to use a
scraper or wire brush later, if you need to, to
get all the rust or dirt off. See“Changing a Flat
Tire”in the Index.
5-62
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.
5-94
2003 - Yukon/Yukon XL