1998 GMC SIERRA light

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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While the tires available on General Motors passenger
cars and light trucks may vary with respect to these
grades, they must also conform to Federal safety
requirements and additional General Motors Tire
Performance Criteria (TPC) standards.
Treadwear
The treadwear grade is a comparative rating based on
the wear rate of the tire when tested under controlled
conditions on a specified government test course. For
example, a tire graded 150 would wear one and a half
(1 1/2) times as well on the government course as a tire
graded
100. The relative performance of tires depends
upon the actual conditions of their use, however, and
may depart significantly from the norm due to variations
in driving habits, service practices and differences in
road characteristics and climate.
Traction -- A, B, C
The traction grades, from highest to lowest, are A, B, and
C, and they represent the tire’s ability to stop
on wet
pavement
as measured under controlled conditions on
specified government test surfaces of asphalt and concrete.
A tire marked C may have poor traction performance. Warning:
The traction grade assigned to this tire is based
on braking (straight ahead) traction tests and does not
include cornering (turning) traction.
Temperature -- A, B, C
The temperature grades are A (the highest), B, and C,
representing the tire’s resistance to the generation of
heat and its ability
to dissipate heat when tested under
controlled conditions
on a specified indoor laboratory
test wheel. Sustained high temperature can cause the
material of
the tire to degenerate and reduce tire life, and
excessive temperature can lead to sudden tire failure.
The grade
C corresponds to a level of performance
which
all passenger car tires must meet under the
Federal Motor Vehicle Safety Standard
No. 109.
Grades B and A represent higher levels of performance
on the laboratory test wheel than the minimum required
by law.
Warning: The temperature grade for this tire is
established for a tire that is properly inflated and
not
overloaded. Excessive speed, underinflation, or
excessive loading, either separately or in combination,
can cause heat buildup and possible tire failure.
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Appearance Care Materials Chart
PART NUMBER SIZE DESCRIPTION USAGE
994954 23 in. x 25 in. Polishing Cloth - Wax Treated
Exterior polishing cloth
1050172 16
oz. (0.473 L) Tar and Road Oil Remover Removes tar, road oil and asphalt
1050173 16
oz. (0.473 L) Chrome Cleaner and Polish Use on chrome, stainless steel, nickel, copper and brass
1050 174 16
oz. (0.473 L) White Sidewall Tire Cleaner Removes soil and black marks from whitewalls
1050214 32
oz. (0.946 L) Vinyl Cleaner Cleans vinyl tops, upholstery and convertible tops
1050427 23
oz. (0.680 L) Glass Cleaner Removes dirt, grime,
smoke and fingerprints
1052870
16 oz. (0.473 L) Wash Wax Concenmace Cleans and lightly waxes ~.
1052918”” 8 oz. (0.237 L) Armor All Protectant Protects
leather, wood, acrylics, Plexiglas TM , plastic,
rubber and vinyl
1052925
[ 16 oz. (0.473 L) I Multi-Purpose Interior Cleans carpets, seats, interior trim, door panels
I Cleaner and floor mats I I
1052929 I 16 oz. (0.473 L) I Wheel Cleaner I Spray on and rinse with water
1052930
8 oz. (0.237 L) Capture Dry Spot Remover
Attracts, absorbs and removes soils
12345002
16 oz. (0.473 L) Armor All” Cleaner Cleans
and shines a variety of surface types
12345721 2.5
sq. ft. Synthetic Chamois
Shines vehicle without scratching
12345725 12
oz. (0.354 L) Silicone Tire Shine Spray
on tire shine
12377964 16
oz. (0.473 L) Finish Enhancer Removes dust, fingerprints andsurface contaminants
12377966 16
oz. (0.473 L) Cleaner Wax Removes light scratches and oxidation and protects fish
12377984
I 16 oz. (0.473 L) I Surface Cleaner I Removes contaminants, blemishes and swirl marks
See your General Motors Parts Department for these products.
** Not recommended for use on instrument panel vinyl.
See “Fluids and Lubricants’’ in the Index.
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Headlamps Fuses and Circuit Breakers
The headlamp wiring is protected by an internal circuit
breaker. An electrical overload will cause
the lamps
to go on and off, or
in some cases to remain off. If
this happens, have your headlamp wiring checked
right away.
Windshield Wipers
The windshield wiper motor is protected by a circuit
breaker and
a fuse. If the motor overheats due to heavy
snow, etc., the wiper will stop
until the motor cools. If
the overload is caused by some electrical problem and
not snow, etc., be sure to get it fixed.
Power Windows and Other Power Options
Circuit breakers protect the power windows and other
power accessories. When the current load is too heavy,
the circuit breaker opens and closes, protecting the
circuit
until the problem is fixed or goes away. The wiring circuits
in your vehicle are protected from
short circuits by
a combination of fuses, circuit breakers
and fusible thermal links.
This greatly reduces the
chance
of fires caused by electrical problems.
Look at the silver-colored band inside the fuse. If the
band is broken or melted, replace the fuse. Be sure you
replace
a bad fuse with a new one of the identical size
and rating.
If you ever have
a problem on the road and don’t have a
spare fuse, you can “borrow” one that has the same
amperage. Just pick some feature
of your vehicle that
you can get along without
-- like the radio or cigarette
lighter
-- and use its fuse, if it is the correct amperage.
Replace
it as soon as you can.
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FuseKircuit Breaker
3
4
Usage
Courtesy Lamps, Cargo Lamp,
Glove Box Lamp, Dome/Reading
Lamps, Vanity Mirrors,
Power Mirrors
Instrument Cluster, DRL Relay,
Lamp Switch, Keyless Entry,
Low Coolant Module, Illuminated Entry Module,
DRAC (Diesel Engine)
Not Used
Cruise Control
Auxiliary Power Outlet
Crank
License Lamp, Parking Lamps,
Taillamps,
Roof Marker Lamps,
Tailgate Lamps, Front
Sidemarkers, Fog Lamp Relay,
Door Switch Illumination,
Fender Lamps, Headlamp Switch Illumination
FuseKircuit
Breaker
10
11
12
13
14
15
I6
17
18
19
Usage
Air Bag System
Wiper Motor, Washer Pump
A/C,
A/C Blower,
High Blower Relay
Power
Amp, Cigarette Lighter,
Door Lock Relay,
Power Lumbar Seat
4WD Indicator, Cluster, Comfort
Controls, Instrument Switches,
Radio Illumination,
Chime Module
DRL Relay,
Fog Lamp Relay
Front and Rear Turn Signals,
Back-up Lamps, BTSl Solenoid
Radio (Ignition)
4WAL/VCM, ABS. Cruise Control
Radio (Batterv)
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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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At Least Twice a Year Manual Transmission Check
Restraint System Check
Make sure the safety belt reminder light and all your
belts, buckles, latch plates, retractors and anchorages are
working properly. Look
for any other loose or damaged
safety belt system parts.
If you see anything that might
keep a safety belt system from doing its
job, ha\:e it
repaired. Have any torn or frayed safety belts replaced.
Also look for any opened or broken
air bag coverings,
and have them repaired or replaced. (The air
bag system
does
not need regular maintenance.)
Wiper Blade Check
Inspect wiper blades for wear or cracking. Replace blade
inserts that appear worn
or damaged or that streak or
miss areas
of the windshield. Also see "Wiper Blactes,
Cleaning"
in the Index.
Air Cleaner Filter Restriction Indicator Check
Your vehicle has an indicator on the engine that lets you
know when the air cleaner filter
is dirty and needs to be
changed. Check indicator at least twice
a year or when
your
oil is changed. See "Air Cleaner" in the Index for
more information. Inspect your air cleaner filter
restriction indicator more often
if the vehicle is used in
dusty areas or under off road conditions. Check the transmission fluid
level; add
if needed. See
"Manual Transmission"
in the Index. Check for leaks.
A fluid loss may indicate a problem. Have the system
inspected and repaired
if needed.
Automatic Transmission Check
Check the transmission fluid level: add if needed. See
"Automatic Transmission"
in the Index. A fluid loss may
indicate a problem. Check the system and repair
if needed.
Hydraulic Clutch System Check
Check the fluid level in the clutch reservoir. See
"Hydraulic Clutch Fluid"
in the Index. A fluid loss in
this system could indicate a problem. Have the system
inspected and repaired at once.
At Least Once a Year
Key Lock Cylinders Service
Lubricate the key lock cylinders with the lubricant
specified
in Part D.
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