2003 GMC YUKON maintenance schedule

Brakes
Brake Fluid
Your brake master cylinder reservoir isfilled with DOT-3
brakefluid. SeeEngine Compartment Overview on
page 5-12for the location of the reservoir.
There are only two reasons why the brakefluid level in
the reservoir might go down. Thefirst is that the
brakefluid goes down to an acceptable level during
normal brake lining wear. When new linings are put in,
thefluid level goes back up. The other reason is
thatfluid is leaking out of the brake system. If it is, you
should have your brake systemfixed, since a leak
means that sooner or later your brakes won’t work well,
or won’t work at all.
So, it isn’t a good idea to“top off”your brakefluid.
Adding brakefluid won’t correct a leak. If you addfluid
when your linings are worn, then you’ll have too
muchfluid when you get new brake linings. You should
add (or remove) brakefluid, as necessary, only when
work is done on the brake hydraulic system.
{CAUTION:
If you have too much brakeuid, it can spill on
the engine. Theuid will burn if the engine is
hot enough. You or others could be burned,
and your vehicle could be damaged. Add brake
uid only when work is done on the brake
hydraulic system. See“Checking Brake Fluid”
in this section.
Refer to the Maintenance Schedule to determine when
to check your brakefluid. SeePart C: Periodic
Maintenance Inspections on page 6-15.
5-40
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

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

Maintenance Schedule......................................6-2
Introduction...................................................6-2
Your Vehicle and the Environment....................6-2
Maintenance Requirements..............................6-2
How This Section is Organized.........................6-3
Part A: Scheduled Maintenance Services...........6-4
Using Your Maintenance Schedule....................6-4
Scheduled Maintenance...................................6-5
Part B: Owner Checks and Services................6-11
At Each Fuel Fill..........................................6-11
At Least Once a Month.................................6-11
At Least Twice a Year...................................6-12At Least Once a Year
...................................6-12
Part C: Periodic Maintenance Inspections
.........6-15
Steering and Suspension Inspection
................6-15
Exhaust System Inspection
............................6-15
Fuel System Inspection
..................................6-15
Engine Cooling System Inspection
...................6-16
Transfer Case and Front Axle (Four-Wheel
Drive) Inspection
.......................................6-16
Brake System Inspection
................................6-16
Part D: Recommended Fluids and Lubricants
. . . .6-17
Part E: Maintenance Record
...........................6-19
Section 6 Maintenance Schedule
6-1
2003 - Yukon/Yukon XL

Maintenance Schedule
Introduction
Important: Keep engine oil at the proper level and
change as recommended.
Have you purchased the GM Protection Plan? The Plan
supplements your new vehicle warranties. See your
Warranty and Owner Assistance booklet or your dealer
for details.
Your Vehicle and the Environment
Proper vehicle maintenance not only helps to keep your
vehicle in good working condition, but also helps the
environment. Improper vehicle maintenance can
even affect the quality of the air we breathe. Improper
fluid levels or the wrong tire inflation can increase
the level of emissions from your vehicle. To help protect
our environment, and to keep your vehicle in good
condition, be sure to maintain your vehicle properly.
Maintenance Requirements
Maintenance intervals, checks, inspections and
recommended fluids and lubricants as prescribed in this
manual are necessary to keep your vehicle in good
working condition. Any damage caused by failure
to follow scheduled maintenance may not be covered by
warranty.
6-2
2003 - Yukon/Yukon XL