
Specification Charts
Replacement Parts
Replacement part numbers listed in this section are based on the latest
information available at the time of printing, and are subject \
to change. If a
part listed in this manual is not the same as the part used \
in your vehicle
when it was built, or
if you have any questions, please contact your GM truck
dealer.
Engine Identification
Liter Produced Fuel VIN
Displacement Type
U.S. TBI N
V8 7.4 H.D.
us. Diesel F V8 6.5
H.D. U.S. Diesel J V8 6.2
L. D. us. Diesel C V8 6.2
US., Can.
TBI K V8
5.7
L. D. US., Can.
TBI H
V8 5.0
U.S. TBI 2 V6
4.3
Emissions
BY
System
Engine Code
*
*
*
*Light Duty Emissions with 8500 GVWR and below or:
Heavy Duty Emissions with 8501 GVWR and above.
TO035
Wheel Nut Torque
MODEL I DESCRIPTION I TORQUE I
C 1500 5 bolts (14mm) 120 ft. Ibs. (160 Nmm)
K 1500 & C-K 2500 6 bolts f14mm) 120 ft. Ibs. (1 60 N.m)
C-K
2500 (w/C6P) 8 bolts (14mm) 120 ft. Ibs. (160 Nmm)
C-K 3500 Single Rear Wheels 8 bolts (14mm) 120
ft. Ibs.
(1 60 N-m)
C3500 Dual Rear Wheels
8 bolts (14mm) 140 ft. Ibs. (190
N-m)
C3500 HD -Front
5 bolts (5/8 in.) 175 ft. Ibs. (240 Nsm)
TO040
--Rear
10 bolts (5/8 in.)
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Scheduled Maintenance Services
Scheduled Maintenance Services
This part tells you the maintenance services that you should h\
ave done and
the times you should schedule them. Your GM dealer knows your vehicle best
and wants you
to be happy with it. If you go to your dealer for your service
needs, you’ll know that GM-trained and supported service peop\
le will perform
the work using genuine GM parts.
These schedules are for vehicles that:
carry passengers and cargo within the recommended limits. You will find
these limits on your vehicle’s Certification Label. See “L\
oading Your
Vehicle” in the Index.
are driven on regular road surfaces, and within legal driving \
limits.
are driven off-road in the recommended manner. See the Index U\
nder
use the recommended fuel. See “Fuel” in the Index.
“Off Road Driving With Your Four Wheel Drive Vehicle.”
selecting The Proper Maintenance Services
To find the proper maintenance schedule for your vehicle, you must\
know two
things. What engine your vehicle has, and how you use your ve\
hicle. Your
engine type will tell you which chart to use, and your drivin\
g conditions will
tell you which schedule to use. The charts are found later in\
this section.
Selecting the Proper Maintenance Chart
Your engine type (Gasoline or Diesel) and its emissions classificat\
ion (Light
Duty 3r Heavy Duty Emissions) will tell you which maintenance \
chart
to use.
Find your Vehicle Identification Number (VIN), and look at th\
e eighth character
to see what your engine code is. Then use the following Engine E\
missions
Classifications table
to find your emissions classification.
Your VIN is on the plate on the top left corner of your instrument panel,
the Certification Label and on the Service Parts Identification \
Label. See “Vehicle Identification Number” in the Index.
If your engine has more than one emissions classification, look at\
your
Certification Label to see what your Gross Vehicle Weight Ratin\
g
(GVWR)
is. See “Loading Your Vehicle” in the Index.
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VIN Code
Z
H
K
C
J
F
N
~~~
Engine Description
with 8500 GVWR and below 7~ ! .-
with 8501 GWVR and' above
4.3L V6/TBI
5.0L V8/TBI
5.7L V8/TBI
with 8500 GVWR and belowk=
*&$
with 8501 GVWR and abov-sd
6.2L V8IDiesel
L.
6.2L V8/Diesel >c<
6.5L V8/Diesel g$ c
7.4L V8/TBI I
Except 454 SS Model 'g
with 454 SS Model ;
J= tb-
-1
L..
HD LD
LD
HD
LD
HD
HD
HD LD
TO268
NOTE: TBI Is a throttle body injection system.
Selecting the Proper Maintenance Schedule
Here ,is how to tell which schedule to follow once you find the proper
maintenance chart to use.
MAINTENANCE SCHEDULE I
Is any one of these true for your vehicle?
Most trips are less than 4 miles (6 kilometers).
Most trips are less than 1.0 miles (16 kilometers), and the outside
temperatures are below freezing.
The engine is at low speed most of the time (as in door-to-door delivery,
You operate in dusty areas or off-road frequently.
You tow a trailer
stop-and-go traffic,
or commercial use).
n;r- .I '.
---. - .
-. . r- IA m. : .. 1: . >.' +--,-P~l*~ -L.
If any one (or more) of these is true for your driving, follow Schedule 1.
Schedule I is shown by a plus sign (t) on the chart. &
MAINTENANCE SCHEDULE II
Follow Schedule II ONLY if none of the above conditions are true. Schedule- -
II is shown by a dot (.) on the chart. I
-
L .. -
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6. AIR CLEANER FILTER REPLACEMENT* -Replace at every 30,000
miles (50 000 km) or more often under dusty conditions. Ask your dealer
for the proper replacement intervals for your driving conditions\
.
7. FRONT WHEEL BEARING REPACK (2 WHEEL DRIVE ONLY) -Clean
and repack the front wheel bearings at each brake relining, or\
at the specified interval, whichever comes first.
8.
TRANSMISSION SERVICE
Automatic Transmission
-Change the transmission fluid and filter every
15,000 miles (25 000 km) for vehicles under 8,600 GVWR or every
12,000 miles (20 000 km) for vehicles over 8,600 GVWR if the vehicle
is mainly driven under one or more of these conditions:
In heavy city traffic.
Where the outside temperature regularly reaches 90°F (32°C\
) or
higher.
In hilly or mountainous terrain.
Frequent trailer pulling.
Uses such as taxi, police, delivery or other commercial service\
.
If the vehicle is not used mainly under any of these conditions, change
the fluid and filter every 30,000 miles
(50 000 km) for vehicles under
8600 GVWR or every
24,000 miles (40 000 km) for vehicles over 8600
GVWR. See “Automatic Transmission Fluid” in the Index for more
information.
Manual Transmission -Transmission fluid does not require periodic
changing.
Regulator Valve System for any worn, plugged or collapsed hoses. Have
the system checked as described in the Service Manual.
9.
CDRV SYSTEM INSPECTION* -Check
the Crankcase Depression
10. FUEL FILTER REPLACEMENT* -Replace the fuel filter at the specified
interval
or sooner if clogged.
11. SPARK PLUGS REPLACEMENT* -Replace spark plugs with the type
listed in Section
6. See “Specification Charts” in the Index.
12.
SPARK PLUG WIRE INSPECTION* -Clean wires and inspect for burns,
cracks or other damage. Check the wire boot fit at the distributor and at
the spark plugs. Replace wires as needed.
*An Emission Control Service
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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.
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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.
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