1998 GMC SIERRA brake

Checking Brake Fluid
You can check the brake fluid without taking off the cap.
Just look at 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 the
MIN but not over the
MAX mark or the top
of the window on the side of
the reservoir. fluid
-- such
as Delco Supreme llw (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:
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.
I I
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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 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).
I
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.
I 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 immediately. 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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Wheel Alignment and Tire Balance
The wheels on your vehicle were aligned and balanced
carefully at the factory to give you the longest tire life
and best overall performance.
Scheduled wheel alignment and wheel balancing are not
needed. However,
if you notice unusual tire wear or
your vehicle pulling one way or the other, the alignment
may need to be reset.
If you notice your vehicle
vibrating when driving on a smooth road, your wheels
may need to be rebalanced.
Wheel Replacement
Replace any wheel that is bent, cracked, or badly rusted
or corroded. If wheel nuts keep corning loose, the wheel,
wheel bolts and wheel nuts should be replaced. If the
wheel leaks
air, replace it (except some aluminum
wheels, which can sometimes be repaired). See your
dealer if any
of these conditions exist.
Your dealer will know the kind of wheel you need.
Each new wheel should have the same load-carrying
capacity, diameter, width, offset and be mounted the
same way as the one it replaces.
If you need to replace any of your wheels, wheel bolts
or wheel nuts, replace them only with new
GM original equipment
parts. This way, you will be sure to have the
right wheel, wheel bolts and wheel nuts for your vehicle.
~ Using the wrong replacement wheels, wheel bolts
or wheel nuts on your vehicle can be dangerous.
It could affect the braking and handling of your
vehicle, make your tires lose air and make you
lose control. You could have a collision in which
you or others could be injured. Always use
the correct wheel, wheel bolts and wheel nuts
for replacement.
~
NOTICE:
The wrong wheel can also cause problems with
bearing life, brake cooling, speedometer or
odometer calibration, headlamp aim, 'bumper
height, vehicle ground clearance and tire or tire
chain clearance to the body and chassis.
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Fuse/Circuit Breaker Usage
20
21
22
23
24
A
B
PRNDL, Automatic Transmission,
Speedometer, Check Gages
Warning Light
Security/Steering
Not Used
Not Used
Front Axle,
4WD Indicator Lamp,
TP2 Relay (Gasoline Engine)
Power Door Lock, Six-Way Power Seat, Keyless Entry Module
Power Windows
Underhood Fuse/Relay Center
The underhood fusehelay center is located in the rear of
the engine compartment near the brake fluid reservoir.
Move the retainer clips
for the cover to access the
fuse block.
You can remove fuses with a fuse extractor. The fuse
extractor
is mounted to the interior fuse block. TO
remove fuses
if you don’t have a fuse extractor, hold the
end of the fuse between your thumb and index finger
and pull straight out.
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STARTER RELAY
[-I
[-I
[T)
I BLOWER
n STOPiHAZ
Name
ECM-B RR DEFOG
IGN-E
FUEL
SOL
GLOW PLUG
Usage
Horn, Underhood Lamps
Auxiliary Fan
Injectors, PCM/VCM
Not Used
Air Conditioning
Not Used
Ignition Switch, EGR, Canister
Purge, EVRV Idle Coast Solenoid,
Heated
02, Fuel Heater
(Diesel Engine), Water Sensor
(Diesel Engine)
HTD ST-RR Not Used
LIGHTING Headlamp and Panel Dimmer
BATT Battery, Fuse Block Busbar
IGN-A Ignition Switch
IGN-B Ignition Switch Switch,
Fog and Courtesy Fuses
ABS Anti-Lock Brake Module
BLOWER High Blower Relay
STOP/HAZ Stoplamps
HEATED SEATS Not Used
6-75
Usage
Fuel Pump, PCM/VCM
Rear Window Defogger
Auxiliary Fan Relay Coi
il, AIC
Compressor Relay, Hot Fuel
Module, Dual Tanks
Fuel Solenoid (Diesel Engine)
Glow Plugs (Diesel Engine)
Name
HORN
AUX FAN
ECM- 1
HTD ST-FR
AIC HTD MIR
ENG-
1
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Maintenance Schedule
Short Trip/City Definition -- Gasoline Engines
Follow the Short Trip/City Maintenance Schedule if any
one of these conditions is true for your vehicle:
Most trips are less than 5 to 10 miles (8 to I6 km).
This is particularly important when outside
temperatures are below freezing.
Most trips include extensive idling (such as frequent
driving
in stop-and-go traffic).
You operate your vehicle in dusty areas or
off-road frequently.
You frequently tow a trailer.
If the vehicle is used for delivery service, police, taxi
or other commercial application.
One oj*tlw reclsorzs yo14 sl~or.~ld~foIlo~~~ this scI~edniv if
you operate yo1.w vehicle urlcler CIIZJ ojthese cor-zditions
is that these cwm1ition.s CCJLIS~ eqirw oil to break
dOC1!12 Sool-zel:
Short Trip/City Intervals -- Gasoline Engines
Every
3,000 Miles (5 000 km): Engine Oil and Filter
Change (or 3 months, whichever occurs first). Chassis
Lubrication (or 3 months, whichever occurs first).
Drive Axle Service (or 3 months, whichever
occurs first).
Every 6,000 Miles (10 000 km): Tire Rotation.
Every 15,000 Miles (25 000 km): Shields and
Underhood Insulation Inspection (GVWR above
8,500 lbs. only). Front Wheel Bearing Repack
(2WD only) (or at each brake relining, whichever
occurs first).
Every 30,000 Miles (50 000 km): Fuel Filter
Every 50,000 Miles (83 000 km): Automatic
Replacement.
Transmission Service (vehicles over
8600 GVWR or
driven under severe conditions only).
Every 60,000 Miles (100 000 km): Engine Accessory
Drive Belt Inspection. Fuel Tank, Cap and Lines
Inspection. Exhaust Gas Recirculation System
Inspection. Evaporative Control System Inspection.
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Maintenance Schedule
Long TriplHighway Intervals -- Gasoline Engines
Every
7,500 Miles (12 500 km): Engine Oil and Filter
Change (or every 12 months, whichever occurs first).
Chassis Lubrication (or every
12 months, whichever
occurs first). Drive Axle Service. Tire Rotation.
Every 15,000 Miles (25 000 km): Shields and
Underhood Insulation Inspection (GVWR above
8,500 lbs. only).
Every 30,000 Miles (50 000 km): Fuel Filter
Replacement. Front Wheel Bearing Repack
(2WD only) (or at each brake relining, whichever
occurs first).
Every 50,000 Miles (83 000 km): Automatic
Transmission Service (vehicles over
8600 GVWR
or driven under severe conditions only).
I Long; TripMighway Intervals -- Gasoline Engines I
Every 60,000 Miles (100 000 km): Engine Accessory
Drive Belt Inspection. Fuel Tank, Cap and Lines
Inspection. Exhaust Gas Recirculation System
Inspection. Evaporative Control System Inspection.
Every 100,000 Miles (166 000 km): Spark Plug Wire
Inspection. Spark Plug Replacement. Automatic
Transmission Service (normal conditions). Positive
Crankcase Ventilation (PCV) Valve Inspection.
Every 150,000 Miles (240 000 km): Cooling System
Service (or every
60 months, whichever occurs first).
These intervals only summarize maintenance services.
Be sure to follow the complete maintenance schedule on
the following pages.
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