brake GMC YUKON 2006 Repair Manual

Electric Brake Control Jumper
{CAUTION:
Be sure to use only the correct trailer brake
harness, the one intended for use on your
vehicle. If you use some other trailer brake
harness, even if it seems to t, your trailer
brakes may not work at all. You could have
a crash in which you or others could be
injured. Use only the trailer brake harness
intended for your vehicle. If it is no longer
available to you, be sure to get a proper
replacement from your dealer.This harness is included with your vehicle as part of the
heavy-duty trailer wiring package.
This harness is for an electric brake controller and
includes a trailer battery feed fuse. It should be installed
by your dealer or a qualied service center.
This harness is new for your vehicle, and you will not be
able to use a harness from an earlier model year.
Power Winches
If you wish to use a power winch on your vehicle, only
use it when your vehicle is stationary or anchored.
4-76

Step-Bumper Pad
Your vehicle has a rear step bumper with a rear step
pad at the center of the bumper.
If you will be using the
bumper to tow a trailer,
and your step-bumper has
three cutout circles you
must push out the center
cutout circle to install
the trailer ball.
If your step-bumper has only one cutout circle, you
will have to cut out the circle, then remove it to install
the trailer ball.
Trailer Recommendations
You must subtract your hitch loads from the Cargo
Weight Rating (CWR) for your vehicle. CWR is
the maximum weight of the load your vehicle can
carry. It doesn’t include the weight of the people inside.
But you can gure about 150 lbs. (68 kg) for each
seat. The total cargo load must not be more than
your vehicle’s CWR.
Weigh your vehicle with the trailer attached, so that you
won’t go over the GVWR or GAWR. If you are using
a weight-distributing hitch, weigh the vehicle without
the spring bars in place.
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 4-60.
4-77

Service............................................................5-3
Accessories and Modications..........................5-3
California Proposition 65 Warning.....................5-3
Doing Your Own Service Work.........................5-4
Adding Equipment to the Outside
of Your Vehicle...........................................5-4
Fuel................................................................5-4
Gasoline Octane............................................5-5
Gasoline Specications....................................5-5
California Fuel...............................................5-5
Additives.......................................................5-5
Fuel E85 (85% Ethanol)..................................5-6
Fuels in Foreign Countries...............................5-7
Filling the Tank..............................................5-8
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...................................................5-15
Engine Oil Life System..................................5-18
Engine Air Cleaner/Filter................................5-20
Automatic Transmission Fluid.........................5-22
Engine Coolant.............................................5-25
Coolant Surge Tank Pressure Cap..................5-27
Engine Overheating.......................................5-28
Overheated Engine Protection Operating Mode . . .5-30Cooling System............................................5-30
Engine Fan Noise.........................................5-35
Power Steering Fluid.....................................5-36
Windshield Washer Fluid................................5-37
Brakes........................................................5-38
Battery........................................................5-41
Jump Starting...............................................5-42
Rear Axle.......................................................5-46
Four-Wheel Drive............................................5-48
Front Axle......................................................5-49
Bulb Replacement..........................................5-50
Halogen Bulbs..............................................5-50
Headlamps..................................................5-50
Front Turn Signal, Sidemarker and Daytime
Running Lamps.........................................5-51
Side Identication Marker Lamps.....................5-52
Roof Marker Lamps......................................5-53
Taillamps, Turn Signal, Stoplamps and
Back-up Lamps.........................................5-54
Replacement Bulbs.......................................5-55
Windshield Wiper Blade Replacement..............5-56
Tires..............................................................5-57
Tire Sidewall Labeling...................................5-58
Tire Terminology and Denitions.....................5-61
Ination - Tire Pressure.................................5-63
Section 5 Service and Appearance Care
5-1

Service
Your dealer knows your vehicle best and wants you to
be happy with it. We hope you will go to your dealer
for all your service needs. You will get genuine GM parts
and GM-trained and supported service people.
We hope you will want to keep your GM vehicle all GM.
Genuine GM parts have one of these marks:
Accessories and Modications
When you add non-GM accessories to your vehicle they
can affect your vehicle’s performance and safety,
including such things as, braking, stability, ride and
handling, emissions systems, aerodynamics, durability,
and electronic systems like antilock brakes, traction
control and stability control. Some of these accessories
may even cause malfunction or damage not covered
by warranty.
GM Accessories are designed to complement and
function with other systems on your vehicle. Your
GM dealer can accessorize your vehicle using genuine
GM Accessories. When you go to your GM dealer
and ask for GM Accessories, you will know that
GM-trained and supported service technicians will
perform the work using genuine GM Accessories.
California Proposition 65 Warning
Most motor vehicles, including this one, contain and/or
emit chemicals known to the State of California to
cause cancer and birth defects or other reproductive
harm. Engine exhaust, many parts and systems
(including some inside the vehicle), many uids, and
some component wear by-products contain and/or
emit these chemicals.
5-3

Filling a Portable Fuel Container
{CAUTION:
Never ll a portable fuel container while it is in
your vehicle. Static electricity discharge from
the container can ignite the gasoline vapor.
You can be badly burned and your vehicle
damaged if this occurs. To help avoid injury
to you and others:
Dispense gasoline only into approved
containers.
Do not ll a container while it is inside a
vehicle, in a vehicle’s trunk, pickup bed,
or on any surface other than the ground.
Bring the ll nozzle in contact with the
inside of the ll opening before operating
the nozzle. Contact should be maintained
until the lling is complete.
Do not smoke while pumping gasoline.
Checking Things Under
the Hood
{CAUTION:
An electric fan under the hood can start up
and injure you even when the engine is not
running. Keep hands, clothing and tools away
from any underhood electric fan.
{CAUTION:
Things that burn can get on hot engine parts
and start a re. These include liquids like fuel,
oil, coolant, brake uid, windshield washer
and other uids, and plastic or rubber. You or
others could be burned. Be careful not to drop
or spill things that will burn onto a hot engine.
5-10

A. Engine Air Cleaner/Filter. SeeEngine
Air Cleaner/Filter on page 5-20.
B. Coolant Surge Tank and Pressure Cap.
SeeCooling System on page 5-30andCoolant
Surge Tank Pressure Cap on page 5-27.
C. Air Filter Restriction Indicator (If Equipped).
SeeEngine Air Cleaner/Filter on page 5-20.
D. Engine Oil Dipstick. See “Checking Engine Oil”
underEngine Oil on page 5-15.
E. Automatic Transmission Dipstick. See “Checking
the Fluid Level” underAutomatic Transmission
Fluid on page 5-22.
F. Engine Oil Fill Cap. See “When to Add Engine Oil”
underEngine Oil on page 5-15.
G. Engine Cooling Fan. SeeCooling System
on page 5-30.H. Remote Negative (−) Terminal (GND).
SeeJump Starting on page 5-42.
I. Power Steering Fluid Reservoir. SeePower
Steering Fluid on page 5-36.
J. Remote Positive (+) Terminal. SeeJump Starting
on page 5-42.
K. Brake Master Cylinder Reservoir. See “Brake Fluid”
underBrakes on page 5-38.
L. Underhood Fuse Block. SeeUnderhood Fuse
Block on page 5-109.
M. Battery. SeeBattery on page 5-41.
N. Windshield Washer Fluid Reservoir. See
“Adding Washer Fluid” underWindshield Washer
Fluid on page 5-37.
5-13

A. Engine Air Cleaner/Filter. SeeEngine
Air Cleaner/Filter on page 5-20.
B. Coolant Surge Tank and Pressure Cap.
SeeCooling System on page 5-30andCoolant
Surge Tank Pressure Cap on page 5-27.
C. Air Filter Restriction Indicator (If Equipped).
SeeEngine Air Cleaner/Filter on page 5-20.
D. Engine Oil Dipstick. See “Checking Engine Oil”
underEngine Oil on page 5-15.
E. Automatic Transmission Dipstick. See “Checking
the Fluid Level” underAutomatic Transmission
Fluid on page 5-22.
F. Engine Oil Fill Cap. See “When to Add Engine Oil”
underEngine Oil on page 5-15.
G. Engine Cooling Fan. SeeCooling System
on page 5-30.
H. Remote Negative (−) Terminal (GND).
SeeJump Starting on page 5-42.
I. Remote Positive (+) Terminal. SeeJump Starting
on page 5-42.
J. Power Steering Fluid Reservoir. SeePower Steering
Fluid on page 5-36.
K. Brake Master Fluid Reservoir. See “Brake Fluid”
underBrakes on page 5-38.
L. Underhood Fuse Block. SeeUnderhood Fuse
Block on page 5-109.M. Battery. SeeBattery on page 5-41.
N. Windshield Washer Fluid Reservoir. See
“Adding Washer Fluid” underWindshield Washer
Fluid on page 5-37.
Engine Oil
If the CHECK OIL LEVEL message appears on the
instrument cluster, it means you need to check
your engine oil level right away.
For more information, see CHECK OIL LEVEL under
DIC Warnings and Messages on page 3-56.
You should check your engine oil level regularly; this is
an added reminder.
Checking Engine Oil
It is a good idea to check your engine oil every time you
get fuel. In order to get an accurate reading, the oil
must be warm and the vehicle must be on level ground.
The engine oil dipstick handle is a yellow loop.
SeeEngine Compartment Overview on page 5-12
for the location of the engine oil dipstick.
1. Turn off the engine and give the oil several minutes
to drain back into the oil pan. If you do not do this,
the oil dipstick might not show the actual level.
2. Pull out the dipstick and clean it with a paper towel
or cloth, then push it back in all the way. Remove it
again, keeping the tip down, and check the level.
5-15

How to Check Automatic
Transmission Fluid
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
transmission uid 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, the uid should be at normal
operating temperature, which is 180°F to 200°F
(82°C to 93°C).Get the vehicle warmed up by driving about 15 miles
(24 km) when outside temperatures are above 50°F
(10°C). If it is 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 cold uid 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 for ve minutes if outside temperatures are
50°F (10°C) or more. If it is colder than 50°F (10°C),
you may have to idle the engine longer. Should the uid
level be low during this cold check, you must check
the uid hot before adding uid. Checking the uid hot
will give you a more accurate reading of the uid level.
Checking the Fluid Level
Prepare your vehicle as follows:
1. Park your vehicle on a level place. Keep the
engine running.
2. With the parking brake applied, place the shift lever
in PARK (P).
3. 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).
4. Let the engine run at idle for three minutes or more.
5-23

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