brakes GMC SIERRA 1996 Owner's Manual

Parking on Hills
You really should not park your vehicle, with a trailer
attached,
on a hill. If something goes wrong, your rig
could start
to move. People can be injured, and both
your vehicle and the trailer can be damaged.
But if
you ever have to park your rig on a hill, here’s
how to do it:
1.
2.
3.
4.
5.
6.
Apply your regular brakes, but don’t shift into
PARK (P) yet for an automatic transmission, or into
gear for
a manual transmission.
Have someone place chocks under the trailer wheels.
When
the wheel chocks are in place, release the
regular brakes until the chocks absorb the load.
Reapply the regular brakes. Then apply your
parking brake and shift
into PARK (P) for an
automatic transmission, or REVERSE
(R) for a
manual transmission.
If you have a four-wheel-drive vehicle, be sure
the transfer case
is in a drive gear and not in
NEUTRAL
(N).
Release the regular brakes. It can
be dangerous to get out of your vehicle if
the shift lever
is not fully in PARK (P) with the
parking brake firmly set. Your vehicle can roll.
If you have left the engine running, the vehicle
can move suddenly. You or others could be
injured.
To be sure your vehicle won’t move, even
when you’re on fairly level ground, use the steps
that follow.
If you have four-wheel drive and your transfer
case is in
NEUTRAL (N), your vehicle will be free
to roll, even if your shift lever is in
PARK (P). So,
be sure the transfer case is in a drive gear -- not
in
NEUTRAL (N).
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When You Are Ready to Leave After
Parking on a Hill
1. Apply your regular brakes and hold the pedal down
while
you:
0 Start your engine;
Shift into a gear; and
0 Release the parking brake.
2. Let up on the brake pedal.
3. Drive slowly until the trailer is clear of the chocks.
4. Stop and have someone pick up and store the chocks.
Maintenance When Trailer Towing
Your vehicle will need service more often when you’re
pulling
a trailer. See the Maintenance Schedule for more
on this. Things
that are especially important in trailer
operation are automatic transmission fluid (don’t
overfill), engine oil, axle lubricant, belt, cooling system
and brake adjustment. Each of these is covered
in this
manual, and the Index will help you find them quickly.
If you’re trailering, it’s a good idea
to review these
sections before you start your trip.
Check periodically
to see that all hitch nuts and bolts
are tight.
Trailer Wiring Harness
A seven-wire harness is stored under the rear end of
your vehicle. between the frame rails. An electrical
connector
will need to be installed at the trailer end of
the harness, by a qualified electrical technician. For
additional trailer wiring and towing information please
consult your
GM dealer. Securely attach the harness to
the trailer, then tape or strap it to your vehicle’s frame
rail.
Be sure you leave it loose enough so the wiring
won’t bind or break when turning with the trailer, but
not so loose that it drags on the ground. Store the
harness in its original position. Wrap the harness
together and tie
it neatly so it won’t be damaged. If you
tow a trailer, your Center High-Mounted Stoplamp
(CHMSL) may not be properly visible from behind.
You should select a trailer with
a CHMSL on it or, if
one is not available, have one installed. See your GM
dealer about how to connect your vehicle’s wiring to
a trailer CHMSL.
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-
DW * Winche- Power Take-Off (PTO)
IT you wish to use a power winch on your vehicle, only
use it when your vehicle
is stationary or anchored.
NOTICE:
Using a power winch with the transmission in
gear
may damage the transmission. When
operating
a power winch, always leave the
transmission in
NEUTRAL (N).
Use the regular brakes, set the parking brake, or block
the wheels to keep your vehicle from rolling.
NOTICE:
If you have a PTO that will exceed 35 hp installed
on your vehicle, it could damage the transfer
case or transmission. When having a
PTO
installed on your vehicle, make sure that it will
not exceed
35 hp.
Before using
a PTO, refer to the manufacturer’s or
installer’s instructions.
I NOTICE:
Using a PTO while operating in one place before
the vehicle has reached normal operating
temperature can damage the transfer case or
transmission.
If you will be using the PTO while
operating
in one place, drive and warm up the
vehicle before using the PTO.
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To engage a PTO:
1. Set the parking brake.
2. Shift the transmission into NEUTRAL (Nj.
3. Hold the clutch pedal down and engage the PTO.
NOTICE:
Using a PTO for more than four hours without
driving your vehicle can damage the transfer case
or transmission. If using a PTO for more than
four hours without driving your vehicle, drive
your vehicle for
a while to allow the transfer case
and transmission
to cool.
If you are going to drive the vehicle, shift the
transmission
into the gear you want. Then shift the
transfer case
into the range you want (if you have
four-wheel drive), apply the regular brakes and
release the parking brake.
4. Release the clutch (and the regular brakes) as you
normally would. When you release the clutch, the
PTO will start.
Using a Transfer Case Mounted Power
Take-Off
(Manual Transmission)
1. Set the parking brake,
2. Shift the transfer case into NEUTRAL (N).
3. Hold the clutch pedal down. If the vehicle will
remain
in the same place, shift the transmission into
the highest gear.
4. Engage the PTO.
If you are going to drive the vehicle, shift the
transmission into the gear
you want. Then shift the
transfer case
into the range you want, apply the
regular brakes and release the parking brake.
5. Release the clutch (and the regular brakes) as you
nor~nally would. When you release the clutch, the
PTO will start.
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Using a Transfer Case Mounted Power
Take-Off (Automatic Transmission)
1.
2.
3.
4.
5.
6.
Set the parking brake.
Shift the transfer case into NEUTRAL
(N).
Shift the transmission into NEUTRAL (N).
Engage the PTO.
If you are going to drive the vehicle, shift the
transfer case
into the range yo11 want. Then apply the
regular brakes and release the parking brake.
Shift the transmission to
THIRD (3) to start the PTO.
Release the regular brakes to drive the vehicle.
Step-Bumper Pad
If your vehicle has a rear step bumper, it may
be equipped with
a rear step pad at the center of
the bumper.
If you will be using the
bumper to
tow a trailer,
you must remove the
center cutout circle
to
install the trailer ball. You
must also remove both outer
cutouts to attach the trailer
safety chains.
To remove the pad, lift
the edge of
the pad from
the rear
of the bumper
and swing
it forward.
When
the pad releases
from
the bumper holes,
lift the pad off.
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Brakes
Brake Fluid
Your brake master cylinder
reservoir
is here. It is filled
I with DOT-3 brake fluid.
There are
only two reasons why the brake fluid level in the
reservoir might go down. The first is that
the brake fluid
goes down to an acceptable level during normal brake lining wear. When new linings are put
in, the fluid level
goes back
up. The other reason is that fluid is leaking out
of the brake system. If it is, you should have your brake
system fixed, since a leak
means that sooner or later your
brakes
won’t work well, or won’t work at all.
So, it isn’t a good idea to “top off’ your brake fluid.
Adding
brake fluid won’t correct a leak. If you add fluid
when your linings are worn, then you’ll have
too much
fluid
when you get new brake linings. You should add
(or remove) brake fluid,
as necessary, only when work is
done on the brake hydraulic system.
A CAUTION0
If you have too much brake fluid, it can spill
on the engine. The fluid will burn if the engine
is hot enough. You or others could be burned,
and your vehicle could be damaged. Add brake
fluid only when work
is done on the brake
hydraulic system.
Refer to the Maintenance Schedule to determine when to
check your brake fluid. See “Periodic Maintenance
Inspections”
in the Index.
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Checking Brake 1
You can check the brake fluid without taking off the cap.
Just look at
the window on 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. After
work
is done on the brake hydraulic system,
make sure the level is above
MIN and below the top
of the window.
What to 1
When you do need brake fluid, use only DOT-3
brake fluid -- such as Delco Supreme 11 @ (GM Part
No. 1052535). Use new brake fluid from a sealed
container
only, and always clean the brake fluid
reservoir cap before removing
it.
I I
I A CAUTION: I
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.
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NOTICE:
0
0
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
If you have a C 3500 HD model, it 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).
A’ CAUTION:
I
The brake wear warning sound means that
sooner or later your brakes won’t work well.
That could lead to an accident. When you hear
the brake wear warning sound, have your vehicle serviced.
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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.
Free movement
of brake calipers and properly torqued
wheel nuts
are necessary to help prevent brake
pulsation. When tires
are rotated, inspect.brake calipers
for movement, brake pads for wear, and evenly torque
wheel nuts in the proper sequence
to GM specifications.
If you have rear drum brakes, they don’t have wear
indicators, but
if you ever hear a rear brake rubbing
noise, have the rear brake linings inspected.
Also, the
rear brake drums should be remoQed and inspected each
time the tires are removed for rotation or changing.
When you have the front brakes replaced, have the rear
brakes inspected,
too. I
Brake linings should always be replaced as complete
axle sets.
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.
If your brake pedal goes down farther than normal, your
rear drum brakes may need adjustment. Adjust them by
backing up and firmly applying the brakes a few times.
Replacing Brake System Parts
The braking system on a modern 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.
Vehicles we design and test have top-quality
GM brake
parts
in them, as your vehicle does when it is new. When
you replace parts of your braking system -- for example,
when- your brhke linings wear do.wn and you have
to
haye new ones put in -- be sure you get new genuine
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.
I
I
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Steering Column Lock Check
While parked, and with
the parking brake set, try to turn
the key
to LOCK in each shift lever position.
With an automatic transmission, the key should turn
With a manual transmission, the key should turn
to LOCK only when the shift lever is in PARK (P).
to LOCK only when the shift lever is in
REVERSE
(R).
On vehicles with a key release button, try to turn the key
to LOCK without pressing the button. The key should
turn to LOCK
only when you press the key button.
On all vehicles, the key should come out
only in LOCK. Parking Brake and Automatic Transmission
PARK
(P) Mechanism Check
I CAUTION:
When
you are doing this check, your vehicle
could begin to move.
You or others could be
injured and property could be damaged.
Make
sure there is room in front of your vehicle in case
it begins to roll. Be ready to apply the regular
brake at once should the vehicle begin to move.
Park
on a fairly steep hill, with the vehicle facing
downhill. Keeping your foot
on the regular brake, set
the parking brake.
0 To check the parking brake: With the engine running
and transmission in NEUTRAL
(N), slowly remove
foot pressure from the regular brake pedal.
Do this
until the vehicle
is held by the parking brake only.
To check the PARK (P) mechanism’s holding ability:
With the engine running, shift
to PARK (P). Then
release all brakes.
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