2003 GMC SIERRA Owner's Manual

Checking Brake Fluid
You can check the brakefluid without taking off the cap.
Just look at the brakefluid reservoir. Thefluid level
should be above MIN. If it isn’t 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 brakefluid, use only DOT-3 brake
fluid. Use new brakefluid from a sealed container
only. SeePart D: Recommended Fluids and Lubricants
on page 6-15.
Always clean the brakefluid 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 offluid 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.
Notice:
•Using the wrongfluid 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 offluid.
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•If you spill brakefluid on your vehicle’s painted
surfaces, the paintfinish can be damaged. Be
careful not to spill brakefluid 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 pedalfirmly).
{CAUTION:
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 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 arefirst 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.
SeeBrake System Inspection on page 6-15.
Brake Pedal Travel
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.
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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.
Battery
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. SeeEngine Compartment Overview on
page 5-12for 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
the battery. This will help keep your battery from
running down.
{CAUTION:
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.
Contact your dealer to learn how to prepare your
vehicle for longer storage periods.
Also, for your audio system, seeTheft-Deterrent
Feature on page 3-75.
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Jump Starting
If your battery (or batteries) has run down, you may
want to use another vehicle and some jumper cables to
start your vehicle. Be sure to follow the steps below
to do it safely.
{CAUTION:
Batteries can hurt you. They can be dangerous
because:
•They contain acid that can burn you.
•They contain gas that can explode or
ignite.
•They contain enough electricity to
burn you.
If you don’t follow these steps exactly, some
or all of these things can hurt you.Notice:Ignoring these steps could result in costly
damage to your vehicle that wouldn’t be covered
by your warranty.
Trying to start your vehicle by pushing or pulling it
won’t work, and it could damage your vehicle.
1. Check the other vehicle. It must have a 12-volt
battery with a negative ground system.
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 brakefirmly 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.
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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 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!
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 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.″
SeeEngine Compartment Overview on page 5-12
for more information on location.
{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
flashlight if you need more light.
Be sure the battery has enough water. You
don’t need to add water to the ACDelco
®
battery installed in your new vehicle. But if a
battery hasfiller caps, be sure the right
amount offluid is there. If it is low, add water
to take care of thatfirst. If you don’t, explosive
gas could be present.
Batteryfluid contains acid that can burn you.
Don’t get it on you. If you accidentally get it in
your eyes or on your skin,flush the place with
water and get medical help immediately.
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{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 don’t 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 a remote positive (+) terminal if the
vehicle has one. Negative (−) will go to a heavy,
unpainted metal engine part or a remote
negative (−) terminal if the vehicle has one.
Don’t connect positive (+) to negative (−)oryou’ll
get a short that would damage the battery and
maybe other parts too. And don’t connect the
negative (−) cable to the negative (−) terminal on
the dead battery because this can cause sparks.6. Connect the red
positive (+) cable to the
positive (+) terminal
of the vehicle with the
dead battery. Use
a remote positive (+)
terminal if the
vehicle has one.
7. Don’t let the other end
touch metal. Connect it
to the positive (+)
terminal of the good
battery. Use a remote
positive (+) terminal
if the vehicle has one.
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8. Now connect the black
negative (−) cable to the
good battery’s
negative (−) cable. Use a
remote negative (−)
terminal if the vehicle
has one.
Don’t let the other end touch anything until the next
step. The other end of the negative (−) cable
doesn’tgo to the dead battery. It goes to a heavy,
unpainted metal part, or to the remote negative (−)
terminal on the vehicle with the dead battery.9. Connect the other end
of the negative (−)
cable to the
negative (−) terminal of
the dead battery or
to a remote
negative (−) terminal
if the vehicle has one.
10. Now start the vehicle with the good battery and run
the engine for a while.
11. Try to start the vehicle that had the dead battery.
If it won’t start after a few tries, it probably needs
service.
Notice:Damage to your vehicle may result from
electrical shorting if jumper cables are removed
incorrectly. To prevent electrical shorting, take care
that the cables don’t touch each other or any
other metal. The repairs wouldn’t be covered by
your warranty.
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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
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.
Jumper Cable Removal
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