1997 GMC SIERRA brakes

Power Winches
If you wish to use a power winch on your vehicle, only
use it when your vehicle is stationary or anchored.
I 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.
Power Take-Off (PTO) (Manual Tkansmission)
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.
To engage a PTO:
1. Hold the clutch pedal down.
2. Set the parking brake.
3. Shift the transmission into NEUTRAL (N).
4. Engage the PTO.
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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
transfer case into the range you want (if
you have
four-wheel drive). Then shift the transmission into
the' gear you want, apply the regular brakes and
release the parking brake.
5. Release the clutch (and the regular brakes) as you
normally would. When you release the clutch, the
PTO will start.
To engage a PTO while the vehicle is moving:
1. Hold the clutch pedal down.
2. Shift the transmission into NEUTRAL (N).
3. Engage the PTO.
4. Shift the transmission into the gear you want.
5. Release the clutch as you normally would. When you
release the clutch, the PTO will start.
Using a Transfer Case Mounted Power
Take-Off (Manual Transmission)
1.
2.
3.
4.
5.
6.
Hold the clutch pedal down.
Set the parking brake.
Shift the transfer case into NEUTRAL
(N).
If the vehicle will remain in the same place, shift the
transmission into the highest gear.
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.
Release the clutch (and the regular brakes) as you
normally 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. Set the parking brake.
2. Turn the ignition off.
3. Shift the transfer case into NEUTRAL (N).
4. Shift the transmission into NEUTRAL (N).
5. Engage the PTO.
If you are going to drive the vehicle, shift the
transfer case into the range you want. Turn the
ignition to START. Then apply the regular brakes
and release the parking brake.
6. Shift the transmission to THIRD (3) to start the PTO.
7. Release the regular brakes to drive the vehicle.
Disengaging a Power Take-OFF
1. Turn the ignition off.
2. Put the transmission in PARK (P).
3. Release the PTO
4. Restart the engine.
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
the pad releases from the
bumper holes, lift the
pad
off.
swing it forward. When
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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
6-
3
6-4
6-5
6-8
6- 14
6- 15
6- 19
6-2 1
6-25
6-26
6-26 6-27
6-29
6-32
6-32 Service
Fuel (Gasoline Engine)
Fuels
in Foreign Countries - - Gasoline
Engines
Filling Your Tank
Checking Things Under the Hood
Noise Control System
Engine Oil (Gasoline Engine)
Air Cleaner Filter (Gasoline Engines)
Automatic Transmission Fluid
Manual Transmission Fluid
Hydraulic Clutch
Rear Axle
Four-wheel Drive
Engine Coolant Radiator Pressure Cap (Gasoline Engine)
Thermostat 6-33
6-33 6-35
6-39
6-39
6-49 6-50
6-59
6-60
6-64
6-68
6-69
6-70 6-75
6-76
6-78 Power Steering Fluid
Windshield Washer Fluid
Brakes
Battery
Bulb Replacement
Windshield Wiper Blade
R
Tires
Appearance Care .eplacement
Cleaning the Inside
of Your Vehicle
Cleaning
the Outside of Your Vehicle
Appearance Care Materials
Chart
Vehicle Identification Number (VIN)
Electrical System Replacement Bulbs
Capacities and Specifications
Air Conditioning Specifications
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Brakes
Brake Fluid
Your brake master cylinder
reservoir is here. It
is filled
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.
I
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 Fluid
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 Add
When you do need brake fluid, use only DOT-3 brake
fluid
-- such as Delco Supreme ll@ (GM Part
No. 12377967). Use new brake fluid from a sealed
container only.
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.
' A CAUTION:
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:
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 without wear indicators.
If you ever hear a brake
rubbing noise, have the brake linings inspected.
If your pickup is not a
C 3500 HD model, it has front
disc brakes and rear drum brakes. Disc brake pads
(except
C 3500 HD models) 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
warning sound, have your vehicle serviced.
NOTICE:
Continuing to drive with worn-out brake pads
could result in costly brake repair.
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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 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 removed and inspected each
time the tires are removed for rotation or changing.
When you have the front brake pads replaced, have
the
rear brakes inspected, too.
Brake linings should always be replaced as complete
axle sets.
See “Brake System Inspection” in Section 7 of this manual
under Part
C “Periodic Maintenance Inspections.”
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.
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.
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