2003 GMC SIERRA DENALI brake

Checking Brake Fluid
You can check the brake fluid without taking off the cap.
What to Add
When you do need brake fluid, use only DOT-3 brake
fluid.
Use new brake fluid from a sealed container
only. See
Part Dr Recommended Fluids and Lubricants
on
page 6- 16.
Just look at the brake fluid reservoir. The fluid level
should be above
MIN. If it isn’t have your brake system
checked to see
if there is a leak. Always
clean the brake fluid reservoir cap and the area
around the cap before removing it. This will help
keep dirt from entering the reservoir.
With the wrong kind
of fluid 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 fluid.
After work is done on the brake hydraulic system,
make sure the level is above the MIN but not over the
MAX mark.
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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 wear warning sound means that soon
your brakes won’t work well. That could lead to
an accident. When you hear the brake wear
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- 15
5-41

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
5-12 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.
5-42

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 the automatic
transmission in PARK
(P) before setting the parking
brake.
If you have a four-wheel-drive vehicle, be
sure the transfer case is in a drive gear not in
NEUTRAL.
Notice: If you leave your radio on, it could be badly
damaged. The repairs wouldn’t be covered by
your warranty.
3.
4.
Turn off the ignition on both vehicles. Unplug
unnecessary accessories plugged into the cigarette
lighter or in the accessory power outlets. Turn
off
the radio and all the lamps that aren’t needed.
This will avoid sparks and help save both batteries.
And it could save your radio!
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 behind
a red plastic cover near the engine accessory
drive bracket.
To uncover the remote positive (+)
terminal, open the red plastic cover.
The remote negative
(-) terminal is located on the
engine drive bracket on all
V8 and diesel
engines, and on the thermostat housing on the
8.1L engine. On
V8 engines it is marked ”GND.”
See
Engine Compartment Overview on page 5-12
for more information on location.
5-44

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. Usin,
__ __ wrong replacement wheels,
whc
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 5-69 for more
information.
5-67

Used Replacement Wheels
-
Putting a used wheel 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.
I I
Tire Chains
Don’t use lire chains. There’s not enough
clearance. Tire chains used on a vehicle
without the proper amount sf clearance can cause damage to the brakes, suspension or
other vehicle parts. The area damaged by the
CAUTION: (Continued) tire chains could cause
, -u to lose cc..-rol
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.
If a Tire Goes Flat
It’s unusual for a tire to “blow out” while you’re driving,
especially
if you maintain your tires properly. If air
goes out of a tire, it’s much more likely to leak out
slowly. 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.
5-68

A rear blowout, particularly on a curve, acts much like a Changing a Flat Tire
skid and may require the same correction you’d use
in a skid. In any rear blowout, remove your foot from the
If a tire goes flat, avoid further tire and wheel damage
accelerator pedal. Get the vehicle under control by by driving slowly
to a level place. Turn on your
steering
the way you want the vehicle to go. it may be hazard warning flashers.
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.
C..-nging 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.
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1 in a crisscross
8.
Tighten the nuts firmly
sequence as shown by
turning the wheel
wrench clockwise.
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.
CAUTION: (Continued) 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.
9. When you reinstall the full-size 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.
5-82