2006 GMC YUKON XL check engine

Power Steering Fluid
SeeEngine Compartment
Overview on page 5-12
for reservoir location.
When to Check Power Steering Fluid
It is not necessary to regularly check power steering uid
unless you suspect there is a leak in the system or
you hear an unusual noise. A uid loss in this system
could indicate a problem. Have the system inspected
and repaired.
How to Check Power Steering Fluid
To check the power steering uid, do the following:
1. Turn the key off and let the engine compartment
cool down.
2. Wipe the cap and the top of the reservoir clean.
3. Unscrew the cap and wipe the dipstick with a
clean rag.
4. Replace the cap and completely tighten it.
5. Remove the cap again and look at the uid level
on the dipstick.
The level should be at the FULL COLD mark.
If necessary, add only enough uid to bring the
level up to the mark.
What to Use
To determine what kind of uid to use, see
Recommended Fluids and Lubricants on page 6-13.
Always use the proper uid. Failure to use the proper
uid can cause leaks and damage hoses and seals.
5-36

Windshield Washer Fluid
What to Use
When you need windshield washer uid, be sure to
read the manufacturer’s instructions before use. If you
will be operating your vehicle in an area where the
temperature may fall below freezing, use a uid that
has sufficient protection against freezing.
Adding Washer Fluid
Your vehicle has a low washer uid message that
comes on when the washer uid is low. The message
is displayed for 15 seconds at the start of each
ignition cycle. When the CHECK WASHER FLUID
message is displayed, you will need to add washer
uid to the windshield washer uid reservoir.
Open the cap with the
washer symbol on it.
Add washer uid until the
tank is full. SeeEngine
Compartment Overview
on page 5-12for reservoir
location.Notice:
When using concentrated washer uid, follow
the manufacturer’s instructions for adding
water.
Do not mix water with ready-to-use washer uid.
Water can cause the solution to freeze and
damage your washer uid tank and other parts
of the washer system. Also, water does not
clean as well as washer uid.
Fill your washer uid tank only three-quarters
full when it is very cold. This allows for
expansion if freezing occurs, which could
damage the tank if it is completely full.
Do not use engine coolant (antifreeze) in your
windshield washer. It can damage your washer
system and paint.
5-37

Brakes
Brake Fluid
Your brake master
cylinder reservoir is lled
with DOT-3 brake uid.
SeeEngine Compartment
Overview on page 5-12
for the location of the
reservoir.
There are only two reasons why the brake uid level
in the reservoir might go down. The rst is that the brake
uid goes down to an acceptable level during normal
brake lining wear. When new linings are put in, the
uid level goes back up. The other reason is that uid
is leaking out of the brake system. If it is, you should
have your brake system xed, since a leak means that
sooner or later your brakes will not work well, or will
not work at all.So, it is not a good idea to top off your brake uid.
Adding brake uid will not correct a leak. If you add
uid when your linings are worn, then you will have
too much uid when you get new brake linings.
You should add or remove brake uid, as necessary,
only when work is done on the brake hydraulic system.
{CAUTION:
If you have too much brake uid, it can spill
on the engine. The uid 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 brake uid. SeeScheduled Maintenance
on page 6-4.
5-38

Checking Brake Fluid
You can check the brake uid without taking off the cap.
Look at the brake uid
reservoir. The uid level
should be above MIN.
If it is not, have your
brake system checked to
see if there is a leak.
After work is done on the brake hydraulic system,
make sure the level is above the MIN but not over
the MAX mark.
What to Add
When you do need brake uid, use only DOT-3 brake
uid. Use new brake uid from a sealed container
only. SeeRecommended Fluids and Lubricants
on page 6-13.Always clean the brake uid reservoir cap and the
area around the cap before removing it. This will help
keep dirt from entering the reservoir.
{CAUTION:
With the wrong kind of uid in your brake
system, your brakes may not work well, or they
may not even work at all. This could cause a
crash. Always use the proper brake uid.
Notice:
Using the wrong uid can badly damage brake
system parts. For example, just a few drops of
mineral-based oil, such as engine oil, in your
brake system can damage brake system parts
so badly that they will have to be replaced. Do
not let someone put in the wrong kind of uid.
If you spill brake uid on your vehicle’s painted
surfaces, the paint nish can be damaged. Be
careful not to spill brake uid on your vehicle.
If you do, wash it off immediately. SeeWashing
Your Vehicle on page 5-100.
5-39

{CAUTION:
Using a match near a battery can cause
battery gas to explode. People have been
hurt doing this, and some have been blinded.
Use a ashlight if you need more light.
Be sure the battery has enough water. You do
not need to add water to the battery installed
in your new vehicle. But if a battery has ller
caps, be sure the right amount of uid is there.
If it is low, add water to take care of that rst.
If you do not, explosive gas could be present.
Battery uid contains acid that can burn you.
Do not get it on you. If you accidentally get it
in your eyes or on your skin, ush the place
with water and get medical help immediately.
{CAUTION:
Fans or other moving engine parts can injure
you badly. Keep your hands away from moving
parts once the engine is running.
5. Check that the jumper cables do not have loose
or missing insulation. If they do, you could get a
shock. The vehicles could be damaged too.
Before you connect the cables, here are some
basic things you should know. Positive (+) will go
to positive (+) or to a remote positive (+) terminal
if the vehicle has one. Negative (−) will go to a
heavy, unpainted metal engine part or to a remote
negative (−) terminal if the vehicle has one.
Do not connect positive (+) to negative (−)oryou
will get a short that would damage the battery
and maybe other parts too. And do not connect the
negative (−) cable to the negative (−) terminal on
the dead battery because this can cause sparks.
5-44

Notice:If the jumper cables are connected or
removed in the wrong order, electrical shorting may
occur and damage the vehicle. The repairs would
not be covered by your warranty. Always connect
and remove the jumper cables in the correct
order, making sure that the cables do not touch
each other or other metal.
A. Heavy, Unpainted Metal Engine Part or Remote
Negative (−) Terminal
B. Good Battery or Remote Positive (+) and Remote
Negative (−) Terminals
C. Dead Battery or Remote Positive (+) TerminalTo 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 the
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 remote positive (+) terminal cover,
if equipped, to its original position.
Rear Axle
When to Check Lubricant
It is not necessary to regularly check rear axle uid
unless you suspect there is a leak or you hear an
unusual noise. A uid loss could indicate a problem.
Have it inspected and repaired.
All axle assemblies are lled by volume of uid during
production. They are not lled to reach a certain level.
When checking the uid level on any rear axle, variations
in the readings can be caused by factory ll differences
between the minimum and maximum uid volume. Jumper Cable Removal
5-46

ApplicationCapacities
English Metric
Fuel Tank
Yukon 26.0 gal 98.4 L
Yukon XL (1500 Series) 31.0 gal 117.3 L
Yukon XL (2500 Series) 37.5 gal 140.0 L
Transfer Case Fluid 2.0 qts 1.9 L
Wheel Nut Torque 140 lb ft 190Y
†Oil lter should be changed at every oil change.
After rell, the level must be rechecked. Add enough engine coolant so that the uid is within the proper
operating range.
Engine Specications
Engine VIN Code Transmission Spark Plug Gap
VORTEC™ 4800 V8 V Automatic 0.040 in (1.01 mm)
VORTEC™ 5300 V8 T Automatic 0.040 in (1.01 mm)
VORTEC™ 5300 V8 Z Automatic 0.040 in (1.01 mm)
VORTEC™ 6000 V8 U Automatic 0.040 in (1.01 mm)
VORTEC™ 8100 V8 G Automatic 0.060 in (1.52 mm)
5-115

Maintenance Schedule......................................6-2
Introduction...................................................6-2
Maintenance Requirements..............................6-2
Your Vehicle and the Environment....................6-2
Using the Maintenance Schedule......................6-3
Scheduled Maintenance...................................6-4
Additional Required Services............................6-6
Maintenance Footnotes...................................6-8Owner Checks and Services............................6-9
At Each Fuel Fill..........................................6-10
At Least Once a Month.................................6-10
At Least Once a Year...................................6-11
Recommended Fluids and Lubricants...............6-13
Normal Maintenance Replacement Parts..........6-15
Engine Drive Belt Routing..............................6-16
Maintenance Record.....................................6-17
Section 6 Maintenance Schedule
6-1