Chevrolet 1980 Light Duty Truck User manual

FOREWORD
This manual includes procedures for diagnosis, maintenance and adjust
ments, minor service operations, and removal and installation for com
ponents of hevrolet Light Duty Trucks. Procedures involving disassembly
and assembly of major components for these vehicles are contained in the
1980 hevrolet Passenger ar and Light Duty Truck Unit Repair (Overhaul)
Manual. Wiring diagrams for 1980 trucks are contained in a separate Wiring
Diagram Booklet.
The Section Index on the contents page enables the user to quickly locate
any desired section. At the beginning of each section containing more than
one major subject is a Table of ontents, which gives the page number on
which each major subject begins. An index is placed at the beginning of each
major subject within the section.
Summaries of Special Tools, when required, and specifications are found
at end of major sections.
When reference is made in this manual to a brand name, number, or
specific tool, an equivalent product may be used in place of the recom
mended item.
This manual should be kept in a handy place for ready reference. If pro
perly used, it will enable the technician to better serve the owners of hev
rolet built vehicles.
All information, illustrations and specifications contained in this literature
are based on the latest product information available at the time of publi
cation approval. The right is reserved to make changes at any time without
notice.

IMPORTANT SAFETY NOTICE
Proper service and repair is important to the safe, reliable operation of all
motor vehicles. The service procedures recommended and described in this
service manual are effective methods for performing service operations.
Some of these service operations require the use of tools specially designed
for the purpose. The special tools should be used when and as recommended.
It is important to note that this manual contains various autions and
Notices which should be carefully read in order to minimize the risk of
personal injury to service personnel or the possibility that improper service
methods will be followed which may damage the vehicle or render it unsafe.
It also is important to understand that these autions and Notices are not
exhaustive. The manufacturer could not possibly know, evaluate and advise
the service trade of all conceivable ways in which service might be done
or of the possible hazardous consequences of each way. onsequently,
the manufacturer has not undertaken any such broad evaluation. Accord
ingly, anyone who uses a service procedure or tool which is not recommend
ed must first satisfy himself thoroughly that neither his safety nor vehicle
safety will be jeopardized by the service method he selects.

TABLE OF CONTENTS SECTION
1980
LIGHT DUTY
TRU K
(SERIES 10-35)
HASSIS SERVI E
MANUAL
AUTION
These vehicles contains some parts dimensioned in the metric
system as well as in the customary system. Some fasteners are
metric and are very close in dimension to familiar customary fast
eners in the inch system. It is important to note that, during any
vehicle maintenance procedures, replacement fasteners must
have the same measurements and strength as those removed,
whether metric or customary. (Num ers on the heads of metric
olts and on surfaces of metric nuts indicate their strength.
Customary olts use radial lines for this purpose, while most
customary nuts do not have strength markings.) Mismatched or
incorrect fasteners can result in vehicle damage or malfunction, or
possi ly personal injury. Therefore, fasteners removed from the
vehicle should e saved for re-use in the same locations whenever
possi le. Where the fasteners are not satisfactory for re-use, care
should e taken to select a replacement that matches the original.
For information and assistance, see your dealer.
GENERAL INFORMATION
General Information
Maintenance and Lubrication
HEATING AND AIR CONDITIONING
Heating and Ventilation
Air Conditioning
FRAME AND BUMPERS
Frame and Body Mounts
Bumpers
heet Metal
Body
STEERING, SUSPENSION, WHEELS
AND TIRES
Front Alignment
teering Linkage
Manual teering
Power teering
teering Column
Front uspension
Rear uspension
Wheel and Tires
AXLEPropeller haft and Universal Joint
Rear Axle
Front Wheel Drive
BRAKES
ENGINE
Engine Mechanical
In-Line 6
mall Block
Mark IV
5.7L(Z) 350 Diesel
Engine Cooling
Fuel ystem - Diagnosis
Model 1ME
Model 2 E
Model M2MC
Model M4MC
Fuel upply
Engine Electrical
Emission Control ystems
Engine Exhaust
TRANSMISSION
Automatic
Manual
Clutch
Transfer Case
ELECTRICAL — BODY AND CHASSIS
Lamps and Lighting
Electrical and Wiring
Instrument Panel and Gages
ACCESSORIES
METRIC AND FASTENER INFORMATION
INDEX
OA
OB
1A
IB
2A
2B
2C
2D
3A
3B1
3B2
3B3
3B4
3C
3D
3E
4A
4B
4C
A
A1
A4
A5
A
B
C
C1
C2
C3
C4
C5
D
E
F
7A
7B
7C
7E
8A
8B
8C
10
11
© 1979 General Motors Corporation Printed in U. .A.

GENERAL INFORMATION OA-1
SE TION OA
GENERAL INFORMATION
ONTENTS OF THIS SE TION
General................................................................................................... . 0-1
Vehicle Identification Number ............................................................ . 0-1
Service Parts Identification Sticker..................................................... . 0-1
Vehicle Loading .................................................................................... . 0-1
Engine ode Number........................................................................... . 0-1
Unit and Serial Number Locations..................................................... . 0-3
GENERAL
Information to identify the vehicle and vehicle
components appears in this section. Detailed specifications
on major units are given at the end of each respective section
in this manual.
VEHI LE IDENTIFI ATION NUMBER (VIN)
This is the legal identification of the vehicle. It appears
on a plate which is attached to the left top of the instrument
panel on K and G truck and can be easily seen through
the windshield from outside the vehicle (fig. OA-1). On P10-
20-30 models, the plate is attached to the front of the dash
and toe panel to the left of steering column (fig. 0A-2). The
VIN also appears on the Vehicle ertificates of Title and
Registration.
SERVI E PARTS IDENTIFI ATION STI KER
The Service Parts Identification Sticker (fig. 0A-6) is
provided on all Truck models. On and K models, the
identification sticker be located on the inside of the glove
box door or on G model, the sticker will be located on an
inner hood panel surface. On P models, the sticker is located
on a inner body panel.
OCCL24AF153278] O
ENGINE ODE TYPI AL VIN
The plate lists the vehicle identification number,
wheelbase, and all Production options or Special Equipment
on the vehicle when it was shipped from the factory
including paint information. ALWAYS REFER TO
THIS INFORMATION WHEN ORDERING PARTS.
VEHI LE LOADING
Vehicle loading must be controlled so weights do not
exceed the numbers shown on the Vehicle Identification
Number and/or Rating Plate for the vehicle.
A typical example of a truck in a loaded condition is
shown in Figure 0A-7. Note that the axle or GVW
capabilities are not exceeded.
ENGINE ODE NUMBER
The engine code number indicates manufacturing
plant, month and day of manufacture, and transmission
type. A typical engine number would be F1210TTBB, which
would breakdown thus:
F - Manufacturing Plant (F-Flint, T-Tonawanda)
12 - Month of Manufacture (December)
10 - Day of Manufacture (tenth)
T - Truck
TBB - Transmission and engine type
oMFD. BY GENERAL MOTORS CORPORATION
G V W R f ^ ^ l
GAWR F R O N T ^ ^ ^ GAWR REAR
VIN
o
INFLATION DATA FOR TIRES FURNISHED WITH VEHICLE
SHOWN ON VEHICLE CERTIFICATIO N LABEL
WARRANTY VOIDED If LOADED IN EXCESS OF RATINGS
SEE OWNERS MANUAL FOR OTHER LOADING AND INFLATION DATA O
EXAMPLE ONLY
Fig. 0A-1-Vehicle Identification Number Location ( K and G) Fig. OA-2-V.I.N. Rating Plate (P Model)
LIGHT TRUCK SERVICE MANUAL

OA-2 GENERAL INFORMATION
LIGHT DUTY TRU K
(EX EPT EL AMINO)
VIN SYSTEM IDENTIFI ATION
D13AF100007
DIVISION
- hevrolet
T-GM
HASSIS TYPE
conventional ab
Ghevy Van & Sport Van
onventional ab 4 x 4
PForward ontrol
ODE
ENGINE
DISPLA EMENT TYPE ARB.
D 4.1 L 250 c d L62B
G5.0L 305 c d V82B
L5.7L 350 c d V84B
M5.7L 350 c d V84B
P 5.7L 350 c dV82B
R6.6L400 c d V84B
S7.4L 454 c dV84B
T 4.8 L 292 c d L61B
W7.4L 454 c dV84B
X6.6L 400 c d V84B
z5.7L 350 c d V8Diesel
PLANT SEQUENTIAL NUMBER
ASSEMBLY PLANT
“A' GMAD-Lakewood GA.
"B' GMAD-Baltimore MD.
"F' HEVROLET-Flint Ml.
"J" GMAD-Janesville Wl.
"S' GMAD-St. Louis MO.
"T GMAD-Fremont A.
"O GM Truck-Pontiac Ml.
“ V GM of anada-Oshawa Ont.
"3' HEVROLET-Detroit Ml.
“4'GM of anada-Scarborough Ont.
GMAD-Lordstown OH.
MODEL YEAR
A for 1980
BODY STYLE
2 hassis owl 81 Forward ontrol hassis
3 hassis ab
4 ab & Pick-Up Box or Hi- ube Van
5 hevy Van & Step Van
6 Sport Van & Suburban
7 Motor Home hassis
8 Blazer
MODEL
1-1/2 Ton
2-3/4 Ton
3-1 Ton
4-1/2 Ton (W/HDSusp)
Fig. 0A-3-Vehicle Identification Number
LIGHT TRUCK SERVICE MANUAL

GENERAL INFORMATION OA-3
IMPORTANT: RETAIN THIS PLATE AS A PERMANENT RECORD
Fig. 0A-4- ervice Parts Identification Plate
UNIT AND SERIAL NUMBER LO ATIONS
For the convenience of service technicians and
engineers when writing up certain business papers such as
Warranty Reports, Product Information Reports, or
reporting product failures in any way, the location of the
various unit numbers have been indicated. These unit
numbers and their prefix or suffix are necessary on these
papers for various reasons - such as accounting, follow-up
on production, etc.
The prefixes on certain units identify the plant in which
the unit was manufactured and thereby -permits proper
follow-up of the plant involved to get corrections made
when necessary.
Fig. 0A-5--Typical Vehicle Loading Condition
Always include the prefix in the number.
Axles
hevrolet Built
• On 10 Series, the ode is stamped on Top of Right
Rear Axle Tube.
• On 20-30 Series, the ode is stamped on Top of the
Right Rear Axle Tube.
Dana Built
• On Front Axles, code is stamped on Top Rear of Left
Axle Tube.
• On Rear Axles, code is stamped on Rear Surface of
Right Axle Tube.
Transmissions (Fig. OA-6)
• On 3-Speed Transmissions (except Tremec), the Unit
Number is located on Lower Left Side of ase Just Below
over.
• On Tremec Transmissions, Unit Number is located
on Upper Left Attachment ase (Top Side).
• On Muncie 4-Speeds, Unit Number is located on
Rear Face of ase below Retainer.
• On New Process 205 model 4-wheel drive transfer
case, a build date is on tag attached to front face of transfer
case.• On Automatic 350 Transmission, Unit Number is
Located on Right Rear Vertical Surface of Oil Pan.
• On the Automatic 400 Transmission, Serial Number
is Located on the Light Blue Plate on the Right Side of the
Transmission.
Engines (Fig. OA-7)
• 6- ylinder Engine Unit Number Located on Pad at
Right Hand Side of ylinder Block at Rear of Distributor.
• 8- ylinder Gasoline Engine ode is (305, 350, 400
ID) Located on Pad immediately forward of right hand
cylinder head.
• 8- ylinder Gasoline Engine (454 ID) ode is
located on a pad of the front top center of the engine block
immediately forward of the inlet manifold.
• 8- ylinder Diesel Engine ode is on a label located
on rear face of the left valve cover.
Generators
Generator Unit Serial Number is located on the Drive
End Frame Below the Part Number.
Batteries
Battery ode Number is Located on ell over Top
of Battery.
LOADED-MAXIMUM GVWR: 4900-LBS.
FRONT GAWR: 2944 LBS. REAR GAWR: 2944 LBS.
* Front Curb 2219 lbs.
Front Cargo &
Pass. Load 284 lbs.
2503 lbs.
'Rear Curb 1003 lbs.
Rear Cargo &
Pass. Load 1394 lbs.
2397 lbs.
TOTAL WEIGHT AT GROUND: 4900 lbs.
Curb weight equals the weight of the vehicle without driver,
passenger or cargo, but including fuel and coolant.
LIGHT TRUCK SERVICE MANUAL

OA-4 GENERAL INFORMATION
PRIMARY V.I.N.
LOCATION (Ml 5 SECONDARY V.I.N . LOCATION
To be used only when
suitable for stamping
fW'D ^
PRIMARY V.I.N. LOCATION (MCI
V.I.N . LOCATION (M20
MANUAL
VIEW
PRIMARY V.I.N .
LOCATION (MV4 or M38
SECONDARY V.I.N . LOCATION
To be used only when
primary locationis not
suitable for stamping
V.I.N . LOCATION (OPTIONAL (M40
0
VIEW
V.I.N . LOCATION
(OPTIONAL (M40
AUTOMATI
Fig. 0A-6-Transmission V.I.N. Location
Starters
Starter Serial Number and Production Date are
Stamped on Outer ase, Toward Rear.
DISTRIBUTOR PAD
ENGINE V .I.N .
(OPTIONAL
V8 ENGINE — DIESEL
ENGINE
CASE PAD
ENGINE
V .I.N .
L6 ENGINE
ENGINE V .I.N . #
(OPTIONAL
ENGINE V.I.N .
ENGINE
Fig. 0A-7-Engine V.I.N. Location
LIGHT TRUCK SERVICE MANUAL