
Scheduled Maintenance Sewices
When the wheels are removed for rotation, inspect disc brake pads f\
or wear
and rotors for surface condition.
Also inspect drum brake linings for wear and
cracks. Inspect other brake parts, including drums, wheel cylind\
ers, parking
brake, etc., at the same time. Remove any rust
or dirt from the wheel and
mounting surfaces before mounting the wheel.
Inspect brakes more often if driving habits or conditions resull In
frequent braking.
Owner Checks and Services
Listed below are owner checks and services which should be mad\
e at the
time period specified
to help ensure proper safety, emission performance, and
dependability of your vehicle.
Be sure any necessary repairs are completed at once. Whenever \
any fluids
or lubricants are added to your vehicle, make sure they are the proper ones,
as shown
in this Section.
At Least Once a Month
Tire inflation pressure check -Check the tires for proper inflation. If they
are low, inflate them
to the level specified on the certification label or on the
tire inflation charts. See “Loading Your Vehicle’’ or “Inflation-Tire Pressure” in
the Index.
At Least Once a Year
Key lock cylinder lubrication -Lubricate key lock cylinders with engine oil.
See the “Recommended Fluid and Lubricants’’ chart in this section.
Transmission neutral or clutch start switch operation
CAUTION
~
1. Before you start, be sure you have enough room around the veh\
icle.
2. Firmly apply both the manual parking brake and the regular brake. See
“Brakes” and “Parking Brake” in the Index.
Do not use the accelerator
pedal.
3. Be ready to turn off the engine immediately if it starts.
4. On automatic transmission vehicles, try to start the engine in each gear.
The starter should work only in
P (Park) or N (Neutral).
7-22
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Scheduled Maintenance Services
Service Station Checks
It is important for you or a service station attendant to perform these
under-hood checks at each fuel
fill.
Check the engine oil level and add if necessary.
Check the engine coolant level in the recovery bottle and add if
necessary.
Check the windshield washer fluid level and add if necessary.
See these items in the Index
for information on how to check them.
7-28
ProCarManuals.com

Customer Assistance Information
Service Publications
Information on how to obtain Product Service Publications, Subsc\
riptions and
Indexes as described below is applicable only in the fifty
US. states (and the
District of Columbia) and only for light trucks with GVWR less than
10,000
pounds (4536 kg).
In Canada, information pertaining to Product Service Bulletins a\
nd Indexes
can be obtained by writing to: General Motors of Canada Limited, Service
Publications Department, 1908 Colonel Sam Dr., Oshawa, Ontario
L1 H 8P7.
GMC Truck regularly sends its dealers useful service bulletins \
about GMC
Truck products. GMC Truck monitors product performance in the f\
ield. We
then prepare bulletins for servicing our products better. Now, \
you can get
these bulletins too.
Bulletins cover various subjects. Some pertain to the proper us\
e and care
of
your vehicle. Some describe costly repairs. Others describe inex\
pensive repairs which,
if done on time with the latest parts, may avoid future costly
repairs. Some bulletins tell a technician how to repair a new \
or unexpected
condition. Others describe a quicker way to
fix your vehicle. They can help a
technician service your vehicle better.
Most bulletins apply
to conditions affecting a small number of trucks. Your
GMC Truck dealer or a qualified technician may have
to determine if a
specific bulletin applies to your vehicle.
You can subscribe to all GMC Truck bulletins. This way you’ll g\
et them as
they come out. You can wait a while and get an index to the bulletins. You
can also get individual bulletins. However, you’ll need the \
index to identify
them.
Subscriptions
You can subscribe to all GMC Truck Product Service Publications (P\
SP’s).
This
will include bulletins for all light trucks (less than 10,000 Ibs. [4536 kg]
GVWR)
sold by GMC Truck and will not be limited to PSP’s applicable to any
particular model. When you buy a subscription, you
will receive the PSP’s in
periodic mailings, shortly after they come out.
A subscription costs US.
$75,00 ($85.00 including a special binder) and it entitles you to all PSP’s
published by GMC Truck during the model year. You can purchase a
subscription by sending a check or money order to GMC Truck Service
Publications, Post Office Box 436006, Pontiac, Michigan 48343 al\
ong with the
order form located at the end of this section. You may get additional
subscription ordering forms by calling the toll-free number show\
n in this
section, or you can find them at participating dealerships.
8-6
ProCarManuals.com

Individual PSP’S
If you don’t want to buy all the PSP’s issued by GMC Truck for all models in
the model year, you can buy individual PSP’s, such as those which may
pertain to a particular model. To do this, you will first need
to see our index
of PSP’s.
It provides a variety of information. Here’s what you’ll find in the
index and how you can get one:
What You’ll Find in the Index:
A list of all PSP’s published by GMC Truck in a model year (1989 or
later). PSP’s covering all models of GMC Truck light trucks (less than
10,000 pounds [4536 kg] GVWR) are listed in the same index.
Ordering information so you can buy the specific PSP’s you may want.
Price information for the PSP’s you may want to buy.
How You Can Get an Index:
Indexes are published periodically. Most of the PSP’s which could potentially
apply
to the most recent GMC Truck models will be listed in the most recent
publication for that model year. This means you may want
to wait until the
end
of the model year before ordering an index, if you are interested in
buying PSP’s pertaining to a current model year truck.
Some PSP’s pertaining
to a particular model year vehicle may be published in
later years, and these would be listed in the later year’s index. When you
order an index for a model year that is not over yet, we’\
ll send you the most recently published issue. Check the ordering form for indexes f\
or earlier model
years.
Cut out the ordering form,
fill it out, and mail it in. We will then see to it that
an index is mailed
to you. There is no charge for indexes for the 1989-1 993
model years.
Toll-Free Telephone Number
If you want an additional ordering form for an index or a subscription, just
call toll-free and we’ll be happy
to send you one. Automated recording
equipment will take your name and mailing address. The number
to call is
1-800-551
-41 23.
8-7
ProCarManuals.com

Customer Assistance haformation
Copies at Participaiing Dealers
Copies of Indexes and individual PSP’s are at your participating GMC Truck
dealer. You can ask
to see them.
A VERY IMPORTANT REMINDER: These PSP’s are meant for technicians.
They are not meant for the “do-it-yourselfer,” Technicians \
have the equipment,
tools, safety instructions, and know-how to do a job quickly a\
nd safely.
GMC Truck reserves the right to change these procedures without notice after
November,
1 992.
GMC Truck Service Publications
You can get these Product Service Publications by using the order \
form at
the end of this section. You can
also get Service Manuals and Owner
Publications.
8-8
ProCarManuals.com

1993 SERVICE PUBLICATIONS
ORDERING INFORMATION
You can get manuals that tell how to operate and service your veh\
icle.
To order them, fill out the order form on the next page and send it to
the address below.
GMC Truck Service Publications
Post Office Box 436006 Pontiac, MI 48343
If you have questions or would like to order using your credit c\
ard, call
us TOLL FREE at
1-800-627-5699.
From outside the Continental United States, please call 1-313-45\
5-8016
GLOVE BOX LITERATURE FOR YOUR SIERRA
Manual Form Number Price
Owner’s Manual X-9304 $5.50
Warranty Manual X-931 7 $2.00
Vehicle Storage Manual x-01
01 -
You can also order the Glove Box Literature in a vinyl pottfolio which
includes all of these publications.
Ask for form number 15690052-it
costs
$1 4.00.
SERVICE MANUALS FOR ALL LIGHT DUTY TRUCKS
*Includes Fuel and Emissions Manual X-9336
Model Form Number Price*
1993 C/K Models X-9331 $62.00
1993
G Van x-9357 $70.00
1993 P3
81 PIG Models X-9332 $64.00
1993 Safari X-9330 $62.00
1993
S/T Models X-9329 $6 1 .OO
There are other service manuals you can buy that cover the el\
ectrical
systems and unit repair. Call us to get a catalogue listing o\
f all these
manuals.
PRODUCT SERVICE PUBLICATIONS
Description Form Number Price
* 1990 Model Year Index PSP I 90 Free
1991 Model Year Index PSP I 91 Free
1992 Model Year Index PSP I 92 Free
1993 Model Year Index PSP I 93 Free
1993 Model Year Product Service
Publication Subscription
PSP 93 $75.00
Above Subscription With Binder PSP 93B $85.00
Binder Only PSP B $1 5.00
Prices subject to change without notice.
ProCarManuals.com

INDEX
H
Halogen Bulbs .............................. 6-55
Hazard Warning Flashers
.............. 5-2
Head Restraints
.............................. 1-5
Headlights .......................... 2.53. 6-55
Composite
.................................. 6-56
Halogen
..................................... 6-55
High-Low Beam
........................ 2-44
Reminder
................................... 2-54
Sealed Beam
............................. 6-55
Heating System (with NC)
........... 3-5
Rear Window Defogger
............. 3-8
System Controls
......................... 3-6
Fan Knob
..................................... 3-4
Function Lever
............................ 3-4
Temperature Lever
...................... 3-4
Hitches
........................................... 4-58
Hood Checking Under
........................ 6-17
Latches and Hinge
................... 6-53
Release
...................................... 6-1 7
Horn
............................................... 2-41
Hydraulic Clutch
........................... 6-37
Grease Fitting
............................ 6-39
Hydro-Boost System (Hydraulic Pump)
..................... 6-50
Hydroplaning
................................. 4-39
I
If You’re Stuck In Sand. Mud.
Ice or Snow
.............................. 5-33
Ignition Switch
.............................. 2-1 0
Inflation-Tire Pressure ................. 6-73
Instrument Panel
............... 2-70. 2-76
Diesel Tach Cluster .................. 2-75
Standard Cluster
............ 2-72, 2-73
J
High Beam Indicator Light ...... 2-85
Heating System (without AIC)
..... 3-4
Rear Window Defogger
............. 3-8
Highway Hypnosis
........................ 4-46 Jack Storage
...................... 5.19.
5-31
Jump Starting
................................ 5-3
K
Key Release Lever ....................... 2-11
Keys
................................................. 2-3
L
Lights ............................................. 2-53
Brake System Warning
............ 4-18
Bulb Replacement
......... .6-54, 6-98
Cargo Lamp
.................... 2-58, 6-61
Charging System Light
........... 2-82
Check Gages Light
.................. 2-84
Dome Lights
............................. 2-56
Fender
........................................ 6-59
Fog Lamps
................................ 2-54
Glow Plugs Light
........... 2-16, 2-81
Front ParkinglTurn Signal
........ 6-57
Indicator
..................................... 2-78
Headlights (See “Headlights”-)
Low Coolant Warning
.............. 2-81
Malfunction Indicator
.... 2-83, 6-66
Operation
................................... 2-43
Reading
..................................... 2-57
Service Fuel Filter
.................... 2-80
Side Marker
.............................. 6-58
Rear
................................. 6-62, 6-63
Replacement Chart
.................. 6-98
Roof Marker
.............................. 6-60
Tailgate Marker
......................... 6-60
Underhood Reel Lamp
............ 2-58
Loading Your Vehicle
........ 4-26, 6-67
Truck-Camper
............................ 6-70
Lubrication
..................................... 6-52
Accelerator Control System
.... 6-52
Body ........................................... 6-53
Constant Velocity Joints
......... 6-53
Front Axle
................................. 6-40
Front Shock Absorbers
........... 6-51
Front Suspension and Steering Linkage
................... 6-51
Service Engine Soon
..... 2-83, 6-66
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