brakes GMC SIERRA 1997 Owner's Manual

Safety Chains
You should always attach chains between your vehicle
and your trailer. Cross the safety chains under the tongue
of the trailer so that the tongue will not drop to the road
if it becomes separated from
the hitch. Instructions
about safety chains may be provided by the hitch
manufacturer or by the trailer manufacturer. Follow the
manufacturer’s recommendation for attaching safety
chains and do not attach them to
the bumper. Always
leave just enough slack
so you can turn with your rig.
And, never allow safety chains to drag on the ground.
Trailer Brakes
If your trailer weighs more than 1,000 Ibs. (450 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,OOO psi (20 650 Wa)
of pressure.
The trailer’s brake system will use less than 0.02
cubic inch (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
Towing a trailer requires a certain amount of experience.
Before setting out for the open road, you’ll want to get
to know your rig. Acquaint yourself with the feel of
handling and braking with the added weight of the
trailer. And always keep
in mind that the vehicle you are
driving is now a
good deal longer and not nearly as
responsive as your vehicle
is by itself.
Before you start, check the trailer hitch and platform
(and attachments), safety chains, electrical connector,
lamps, tires and mirror adjustment. If
the trailer has
electric brakes, start your vehicle and trailer moving and
then apply the trailer brake controller by hand to be sure
the brakes are working. This lets you check your
electrical connection at the same time.
During your trip, check occasionally to be sure that the
load is secure, and that the lamps and any trailer brakes
are still working.
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Turn Signals When Towing a Trailer
The arrows on your instrument panel will flash
whenever you signal a turn or lane change. Properly
hooked up, the trailer lamps will also flash, telling other
drivers you’re about to turn, change lanes or stop.
When towing a trailer, the arrows on your instrument
panel will flash for turns even if the bulbs
on the trailer
are burned out. Thus, you may think drivers behind you
are seeing your signal when they are not. It’s important
to check occasionally to be sure the trailer bulbs are
still working.
Driving On Grades
Reduce speed and shift to a lower gear before you start
down a long or steep downgrade. If you don’t shift
down,
you might have to use your brakes so much that
they would get hot and no longer work well.
On
a long uphill grade, shift down and reduce your
speed
to around 45 mph (70 km/h) to reduce the
possibility of engine and transmission overheating. If you have an automatic transmission, you can tow
in
AUTOMATIC OVERDRIVE (a). You
may want to
shift the transmission to THIRD
(3) or, if necessary, a
lower gear selection if the transmission shifts too often
(e.g., under heavy loads and/or hilly conditions).
If you have a manual transmission and you are towing a
trailer, it’s better not to use
FIFTH (5) gear. Just drive in
FOURTH
(4) gear (or, as you need to, a lower gear).
When towing at high altitude on steep uphill grades,
consider the following: Engine coolant will boil at a
lower temperature than at normal altitudes. If
you turn
your engine off immediately after towing at high altitude
on steep uphill grades, your vehicle may show signs
similar to engine overheating.
To avoid this, let the
engine run while parked (preferably on level ground)
with the automatic transmission in
PARK (P) (or the
manual transmission out of gear and the parking brake
applied) for a few minutes before turning the engine
off.
If you do get the overheat warning, see “Engine
Overheating”
in the Index.
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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. Apply your regular brakes, but don't shift into
PARK
(P) yet for an automatic transmission, or into
gear for a manual transmission.
2. Have someone place chocks under the trailer wheels.
3. When the wheel chocks are in place, release the
regular brakes until the chocks absorb
the load.
4. 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.
5. If you have a four-wheel-drive vehicle, be sure
the transfer case is
in a drive gear and not in
NEUTRAL
(N).
6. Release the regular brakes.
c
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
Parkine
on a Hill
1. Apply your regular brakes and hold the pedal down
while you:
Start your engine;
Shift into a gear; and
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.
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.
Check periodically to see that all hitch nuts and bolts
are tight.
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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.
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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
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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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