2003 GMC YUKON DENALI brake

Notice;
Using the wrong fluid 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’ll have to be replaced.
Don’t let someone put
in the wrong kind of fluid.
If you spill brake fluid on your vehicle’s painted
surfaces,
the paint finish can be damaged. Be
careful not to spill brake fluid on your vehicle. If
you do, wash
it off immediately. See
“Appearance Care’’ in the Index.
Brake Wear
Your vehicle has four-wheel disc brakes.
Disc brake pads have built-in wear indicators that make
a high-pitched warning sound when the brake pads
are worn and new pads are needed. The sound
may come and go or be heard all the time your vehicle
is moving (except when you are pushing on the
brake pedal firmly).
~ The brake wea rarl -g sou.-_. ... eans that
soon your brakes won’t work well. That could
lead to an accident. When you hear the brake
wear warning sound, have your vehicle
serviced.
Notice: Continuing to drive with worn-out brake
pads could result in costly brake repair.
Some driving conditions or climates may cause a brake
squeal when the brakes are first applied or lightly
applied. This does not mean something is wrong with
your brakes.
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.
See
Brake System Inspection on page 6-14.
5-38

Brake Pedal Travel Battery
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 braking
system
- 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. 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. See Engine Compartment Overview
on
page 5-72 for 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.
Vehicle Storage
If you’re not going to drive your vehicle for 25 days or
more, remove the black, negative
(-) cable from
+‘-? battery. This will hc’- keep your battery from
Batteries have acid that can burn you and gas
that can explode. You can be badly hurt if you
aren’t careful. See “Jump Starting” next for
tips on working around a battery without
getting hurt.
5-39

Notice: If the other system isn’t a 12-volt system
with a negative ground, both vehicles can be
damaged.
2.
Get the vehicles close enough so the jumper cables
can reach, but be sure the vehicles aren’t touching
each other.
If they are, it could cause a ground
connection you don’t want. You wouldn’t be able
to
start your vehicle, and the bad grounding could
damage the electrical systems.
To avoid the possibility of the vehicles rolling, set
the parking brake firmly on both vehicles involved in
the jump start procedure. Put an automatic
transmission in PARK (P) or a manual transmission
in NEUTRAL before setting the parking brake.
Notice: If you leave your radio on, it could be badly
damaged. The repairs wouldn’t be covered by
your warranty.
3. Turn off the ignition on both vehicles. Unplug
unnecessary accessories plugged into the cigarette
lighter or accessory power outlets. Turn
off the
radio and all lamps that aren’t needed. This
will avoid sparks and help save both batteries.
And it could save your radio!
4. Open the hoods and locate the positive (+) and
negative
(-) terminal locations of the other vehicle.
Your vehicle has a remote positive
(+) jump
starting terminal and a remote negative
(-) jump
starting terminal.
You should always use these
remote terminals instead
of the terminals on the
battery.
The remote positive
(+)
terminal is located under a red plastic cover near
the engine accessory drive
bracket.
To access the
remote positive
(+)
terminal, open the red
plastic cover.
5-41

Wheel Alignment and Tire Balance
The wheels on your vehicle were aligned and balanced
carefully at the factory
to give you the longest tire life
and best overall performance.
Scheduled wheel alignment and wheel balancing are
not needed. However,
if you notice unusual tire wear or
your vehicle pulling one way or the other, the alignment
may need
to be reset. If you notice your vehicle
vibrating when driving on a smooth road, your wheels
may need
to be rebalanced.
Wheel Replacement
Replace any wheel that is bent, cracked, or badly rusted
or corroded.
If wheel nuts keep coming loose, the
wheel, wheel bolts and wheel nuts should be replaced.
If the wheel leaks air, replace it (except some
aluminum wheels, which can sometimes be repaired).
See your dealer
if any of these conditions exist.
Your dealer will know the kind of wheel you need.
Each new wheel should have the same load-carrying
capacity, diameter, width, offset and be mounted
the same way as the one it replaces.
If you need to replace any of your wheels, wheel bolts
or wheel nuts, replace them only with new
GM
original equipment parts. This way, you will be sure to
have the right wheel, wheel bolts and wheel nuts
for your vehicle. Using the wrong replacement wheels, wheel
bolts or wheel nuts on your vehicle can be
dangerous. It could affect the braking and handling
of your vehicle, make your tires lose
air and make you lose control. You could have
a collision in which you or others could be
injured. Always use the correct wheel, wheel
bolts and wheel nuts for replacement.
Notice: The wrong wheel can also cause problems
with bearing life, brake cooling, speedometer or
odometer calibration, headlamp aim, bumper height,
vehicle ground clearance and
tire clearance to the
body and chassis.
See
Changing a Flat Tire on page 5-63 for more
information.
5-6 1

Used Replacement Wheels Tire Chains
-
Putting a used wheel on your vehicle is
dangerous. You can’t know how
it’s been used
or how far
it’s been driven. It could fail
suddenly and cause a crash. If you have to replace
a wheel, use a new GM original
equipment wheel. Don’t use
ti., ch; ... s. There’s
not ,..ough
clearance. Tire chains used
on a vehicle without
the proper amount of clearance can cause
damage to the brakes, suspension or other
vehicle parts. The area damaged by the tire
chains could cause you to lose control of your
vehicle and you or others may be injured
in a
crash. Use another type of traction device only
if its manufacturer recommends
it for use on
your vehicle and tire size combination and road conditions. Follow that manufacturer’s instructions. To help avoid damage to your
vehicle, drive slowly, readjust or remove
the
device if it’s contacting your vehicle, and don’t
spin your wheels.
If you do find traction devices
that will
fit, install them on the rear tires.
5-62

If a Tire Goes Flat
It’s unusual for a tire to “blowout” while you’re driving,
especially
if you maintain your tires properly. If air goes
out
of a tire, it’s much more likely to ieak out siowiy.
But if you should ever have a “blowout”, here are a few
tips about what
to expect and what to do:
If a front tire fails, the flat tire will create a drag that
pulls the vehicle toward that side. Take your foot
off the
accelerator pedal and grip the steering wheel firmly.
Steer to maintain lane position, and then gently brake
to
a stop well out of the traffic lane.
A rear blowout, particularly on a curve, acts much like a
skid and may require the same correction you’d use
in a skid.
In any rear blowout, remove your foot from the
accelerator pedal. Get the vehicle under control by
steering the way you want the vehicle
to go. It may be
very bumpy and noisy, but you can still steer. Gently
brake to a stop
- well off the road if possible.
If a tire goes flat, the next part shows how to use your
jacking equipment to change a flat tire safely.
Changing a Flat Tire
If a tire goes flat, avoid further tire and wheel damage
by driving slowly to a level place. Turn on your
hazard warning
fi hers.
Changing a tire can cause an injury. The
vehicle can slip
off the jack and roll over you
or other people. You and they could be badly injured. Find a level place to change your tire.
To help prevent the vehicle from moving:
1. Set the parking brake firmly.
2. Put the shift lever in PARK (P).
3. Turn off the engine.
4. Put the wheel blocks at the front and rear
of the tire farthest away from the one
being changed. That would be the tire on
the other side
of the vehicle, at the
opposite end.
5-63

incorrect wheel nuts or improperly tightened
wheel nuts can cause the wheel to come loose
and even come
off. This could lead to an
accident. Be sure to use the correct wheel
nuts.
If you have to replace them, be sure to
get new
GM original equipment wheel nuts.
Stop somewhere as soon as you can and have
the nuts tightened with a torque wrench to the
proper torque specification. See “Capacities
and Specifications”
in the Index for wheel nut
torque specification.
Notice: Improperly tightened wheel nuts can lead
to brake pulsation and rotor damage.
To avoid
expensive brake repairs, evenly tighten the wheel nuts in the proper sequence and to the proper
torque specification. See “Capacities and
Specifications” in the index for the wheel nut
torque specification. When
you reinstall the regular wheel and tire, you must
also reinstall the center cap. Place the cap on the
wheel and tap it into place until
it seats flush with the
wheel. The cap only goes
on one way. Be sure to line up
the tab
on the center cap with the indentation on the
wheel.
Storing a Flat or Spare Tire, Jack
and Tools
Storing a jack, a tire, or other equipment in the
passenger compartment of the vehicle could
cause injury. In a sudden stop or collision, loose equipment could strike someone. Store
all these in the proper place.
Notice: An aluminum wheel with a flat tire should
always be stored under the vehicle with the
hoist. However, storing
it that way for an extended
period of time could damage the wheel.
To avoid
this, always stow the wheel properly with the valve stem pointing up and have the wheel repaired as
soon as possible.
5-73

Power Door Lock Relay
DRIVER UNLOCK (Driver’s
Door Unlock
Fuses
VEH CHMSL
LT TRLR ST/TRN
LT TRN
VEH STOP
Usage
Vehicle and Trailer High
Mounted Stoplamp
Left Turn SignaVStop Trailer
Left Turn Signals and
Sidemarkers
Vehicle Stoplamps, Brake Module, Electronic Throttle
Control Module
RT TRLR ST/TRN Right Turn Signal/Stop Trailer
-
RT TRN Right Turn Signals and
Sidemarkers
AUX
PWR 2 I
Rear Cargo Area Power
Outlets
5-89