2001 GMC YUKON Parts for brake system

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CAUTION:
When an air bag inflates, there is dust in the air.
This dust could cause breathing problems for
people with a history of asthma or other
breathing trouble. To avoid this, everyone in the
vehicle should get out as soon as it is safe to do so.
If you have breathing problems but can't get out
of the vehicle after an air bag inflates, then get
fresh air by opening a window or a door.
In many crashes severe enough to inflate an air bag,
windshields are broken by vehicle deformation.
Additional windshield breakage may also occur
from the right front passenger air bag.

Air bags are designed to inflate only once. After an
air bag inflates, you'll need some new parts for your
air bag system. If you don't get them, the air bag
system won't be there to help protect you in another
crash. A new system will include air bag modules
and possibly other parts. The service manual for
your vehicle covers the need to replace other parts.
Your vehicle is equipped with a crash sensing and
diagnostic module, which records information about
the frontal air bag system. The module records
information about the readiness of the system, when
the system commands air bag inflation and driver's
safety belt usage at deployment. The module also
records speed, engine rpm, brake and throttle data.

Let only qualified technicians work on your air
bag systems. Improper service can mean that an
air bag system won't work properly. See your dealer
for service.
NOTICE:
If you damage the covering for the driver's or the
right front passenger's air bag, or the air bag
covering on the driver's and right front
passenger's seatback, the bag may not work
properly. You may have to replace the air bag
module in the steering wheel, both the air bag
module and the instrument panel for the right
front passenger's air bag, or both the air bag
module and seatback for the driver's and right
front passenger's side impact air bag. Do not
open or break the air bag coverings.

2-32
Shifting Out of PARK (P)
Your vehicle has an automatic transmission shift lock
control system. You have to fully apply your regular
brakes before you can shift from PARK (P) when the
ignition is in RUN. See ªAutomatic Transmissionº in
the Index.
If you cannot shift out of PARK (P), ease pressure on
the shift lever and push the shift lever all the way up
into PARK (P) as you maintain brake application.
Then, move the shift lever into the gear you want.
If you ever hold the brake pedal down but still can't
shift out of PARK (P), try this:
1. Turn the key to OFF.
2. Apply and hold the brake until the end of Step 4.
3. Shift the vehicle to NEUTRAL (N).
4. Start the vehicle and then shift to the drive gear
you want.
5. Have the system fixed as soon as you can.
Parking Over Things That Burn
CAUTION:
Things that can burn could touch hot exhaust
parts under your vehicle and ignite. Don't park
over papers, leaves, dry grass or other things that
can burn.

2-73 Brake System Warning Light
With the ignition on, the brake system warning light will
flash when you set the parking brake. The light will flash
if the parking brake doesn't release fully. If you try to
drive with the parking brake engaged, a chime will sound
when the vehicle speed is greater than 3 mph (5 km/h).
Your vehicle's hydraulic brake system is divided into
two parts. If one part isn't working, the other part can
still work and stop you. For good braking, though, you
need both parts working well.
If the warning light comes on, there could be a brake
problem. Have your brake system inspected right away.
United States CanadaThis light should come on briefly when you turn the
ignition key to RUN. If it doesn't come on then, have it
fixed so it will be ready to warn you if there's a problem.
If the light comes on while you are driving, pull off the
road and stop carefully. You may notice that the pedal is
harder to push. Or, the pedal may go closer to the floor.
It may take longer to stop. If the light is still on, have the
vehicle towed for service. See ªTowing Your Vehicleº in
the Index.
CAUTION:
Your brake system may not be working properly
if the brake system warning light is on. Driving
with the brake system warning light on can lead
to an accident. If the light is still on after you've
pulled off the road and stopped carefully, have
the vehicle towed for service.

4-39
If you drive regularly in steep country, or if you're
planning to visit there, here are some tips that can make
your trips safer and more enjoyable. See ªOff
-Road
Drivingº in the Index for information about
driving off
-road.

Keep your vehicle in good shape. Check all fluid
levels and also the brakes, tires, cooling system
and transmission. These parts can work hard on
mountain roads.

Know how to go down hills. The most important
thing to know is this: let your engine do some of
the slowing down. Shift to a lower gear when you
go down a steep or long hill.
CAUTION:
If you don't shift down, your brakes could get
so hot that they wouldn't work well. You would
then have poor braking or even none going
down a hill. You could crash. Shift down to
let your engine assist your brakes on a steep
downhill slope.
CAUTION:
Coasting downhill in NEUTRAL (N) or with the
ignition off is dangerous. Your brakes will have to
do all the work of slowing down. They could get so
hot that they wouldn't work well. You would then
have poor braking or even none going down a hill.
You could crash. Always have your engine running
and your vehicle in gear when you go downhill.

Know how to go uphill. You may want to shift down
to a lower gear. The lower gears help cool your engine
and transmission, and you can climb the hill better.

Stay in your own lane when driving on two
-lane
roads in hills or mountains. Don't swing wide or cut
across the center of the road. Drive at speeds that let
you stay in your own lane.

As you go over the top of a hill, be alert. There could be
something in your lane, like a stalled car or an accident.

You may see highway signs on mountains that warn of
special problems. Examples are long grades, passing or
no
-passing zones, a falling rocks area or winding
roads. Be alert to these and take appropriate action.

4-57 Trailer Brakes
If your trailer weighs more than 2,000 lbs. (900 kg)
loaded, then it needs its own brakes
-- and they must
be adequate. Be sure to read and follow the instructions
for the trailer brakes so you'll be able to install, adjust
and maintain them properly.
Your trailer brake system can tap into the vehicle's
hydraulic brake system only if:

The trailer parts can withstand 3,000 psi
(20 650 kPa) of pressure.

The trailer's brake system will use less than
0.02 cubic inches (0.3 cc) of fluid from your
vehicle's master cylinder. Otherwise, both braking
systems won't work well. You could even lose
your brakes.
If everything checks out this far, make the brake tap
at the port on the master cylinder that sends the fluid
to the rear brakes. But don't use copper tubing for this.
If you do, it will bend and finally break off. Use steel
brake tubing.
Driving with a Trailer
CAUTION:
If you have a rear-most window open and you
pull a trailer with your vehicle, carbon monoxide
(CO) could come into your vehicle. You can't see
or smell CO. It can cause unconsciousness or
death. See ªEngine Exhaustº in the Index. To
maximize your safety when towing a trailer:

Have your exhaust system inspected for
leaks, and make necessary repairs before
starting on your trip.

Keep the rear
-most windows closed.

If exhaust does come into your vehicle
through a window in the rear or another
opening, drive with your front, main
heating or cooling system on and with the
fan on any speed. This will bring fresh,
outside air into your vehicle. Do not use
MAX A/C because it only recirculates the
air inside your vehicle. See ªComfort
Controlsº in the Index.

6-
6-1
Section 6 Service and Appearance Care
Here you will find information about the care of your vehicle. This section begins with service and fuel information,
and then it shows how to check important fluid and lubricant levels. There is also technical information about your
vehicle, and a part devoted to its appearance care.
6
-2 Service
6
-3 Fuel
6
-5 Fuels in Foreign Countries
6
-5 Filling Your Tank
6
-8 Filling a Portable Fuel Container
6
-8 Checking Things Under the Hood
6
-13 Noise Control System
6
-14 Engine Oil
6
-18 Engine Air Cleaner/Filter
6
-20 Passenger Compartment Air Filter
(If Equipped)
6
-21 Automatic Transmission Fluid
6
-25 Rear Axle
6
-25 Four-Wheel Drive
6
-27 Engine Coolant
6
-30 Coolant Surge Tank Pressure Cap
6
-30 Power Steering Fluid6
-32 Windshield Washer Fluid
6
-33 Brakes
6
-37 Battery
6
-37 Bulb Replacement
6
-43 Windshield Wiper Blade Replacement
6
-44 Tires
6
-53 Appearance Care
6
-53 Cleaning the Inside of Your Vehicle
6
-57 Cleaning the Outside of Your Vehicle
6
-61 GM Vehicle Care/Appearance Materials
6
-62 Vehicle Identification Number (VIN)
6
-63 Electrical System
6
-71 Replacement Bulbs
6
-72 Capacities and Specifications
6
-74 Normal Maintenance Replacement Parts

6-35
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 ªAppearance Careº 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).
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.

6-36
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 ªBrake System Inspectionº in Section 7 of this
manual under Part C ªPeriodic Maintenance Inspections.º
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.
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 have to have 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.