Chevrolet CHEVY VAN G10 SERIES User manual

10-30 SERIES
CHEVY VAN-SPO RTVAN
SERVICE MANUAL
C H E V R O L E T , ST 140

© 1972
Gener l
1972
CHEVY VAN nd
SPORT VAN
CHASSIS
SERVICE MANUAL
This manual includes procedures for maintenance and adjust
ments, minor service operations, and removal and installation for
components of Series 10 through 30 Chevy an vehicles. Most
procedures involving disassembly and assembly of major com
ponents for these vehicles are contained in the 1972 Chevrolet
Overhaul Manual. Those few overhaul procedures which differ
will be found at the end of the applicable section of this manual.
The Section Index on this page enables the user to quickly
locate any desired section. At the beginning of each section con
taining more than one major subject is a Table of Contents, 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, are found at the
end of major sections while specifications covering vehicle com
ponents are presented at the rear of the manual.
This manual should be kept in a handy place for ready refer
ence. If properly used, it will enable the technician to better serve
the owners of Chevrolet built vehicles.
All information, illustrations and specifications contained in
this literature are based on the latest product information available
at the time of publication approval. The right is reserved to make
changes at any time without notice.
• • •
CHEVROLET MOTOR DIVISION
Gener l Motors Corpor tion
DETROIT, MICH IGA N
SECTION INDEX
SECTION NAME
A GENERAL INFORMATION
U AND LUBRICATION
1A HEATER AND
AIR CONDITIONING
IB BODY
2 FRAME
3 f r o n t SUSPENSION
A REAR SUSPENSION
4 AND DRIVELINE
5 BRAKES
ENGINE
6K ENGINE COOLING
6M FUEL SYSTEM
6T EMISSION CONTROL SYSTEMS
6Y ENGINE ELECTRICAL
7 CLUTCH AND TRANSMISSIO
O FUEL TANK AND
O EXHAUST SYSTEM
9 STEERING
10 WHEELS AND TIRES
11 CHASSIS SHEET METAL
12 ELECTRICAL—BODY
AND CHASSIS
13 RADIATOR AND GRILLE
14 BUMPERS
15 ACCESSORIES
SPECIFICATIONS
Printed in U.S.A.
Motors Corpor tion
CH EVY VA N SHOP M AN UAL

SECTION O
GENERAL INFORMATION
LUBRICATION
CONTENTS OF THIS SECTION
Page
General Inform ation.......................................................................0-1
Lubrication ......................................................................................0-6
GENERAL INFORMATION
INDEX
Page Page
Model Line U p .................................................................................0-1
eries and Model Identification .................................................0-1
Vehicle Identification Number and
Rating P late .................................................................................0-1
Engine Number ...............................................................................0-1
Unit and erial Number L ocations............................................0-1
MODEL LINE UP
The Chevy Van and portvan are available in the models
listed below:
6-CYLINDER MODEL W/B 8-CYLINDER MODEL
G 11005-06-36 110” GE 11005-06-36
G 11305-06-36 125” GE11305-06-36
G 21005-06-36 110” GE21005-06-36
G 21305-06-36 125” GE21305-06-36
G 31005-06-36 110” G E31005-06-36
G 31305-06-36 125” G E31305-06-36
SERIES AND MODEL IDENTIFICATION
The five digit number preceded by two letters is used to
identify truck series and models. For example, vehicle
G 11005 would be: 0 Light-Duty Forward C ontrol;® L-6
gasoline engine; [T] 3600 lbs.-5600 lbs. GVW; ITD1 60”-65”
Cab-to-Axle dimension; [05] Panel, as listed below:
First Letter-Chassis
E3 — Light-Duty Forward Control
econd Letter—Engine
A - All
E — V-8 Gasoline
El — L-6 Gasoline
First Number—GVW Range
Q ] - 3600-5600 lbs.
2 - 5500-8100 lbs.
3 - 6700-10,000 lbs.
econd and Third Numbers—Cab-to-Axle Dimension
[H - 60-65”
13 - 78-83”
ervice Parts Identification Plate ...............................................0-2
Keys and Locks .............................................................................. 0-3
Pushing to tart V ehicle................................................................0-3
Tow ing................................................................................................0-3
Engine Vehicle Availability...........................................................0 4
Load Capacity C h art......................................................................0-5
Fourth and Fifth Numbers—Body and Brake*
[Q5l - Panel
06 — uburban (Panel Rear Doors)
36 — Deluxe uburban (Panel Rear Doors)
*Hydraulic unless otherwise specified.
VEHICLE IDENTIFICATION NUMBER AND
RATING PLATE
A combination vehicle identification number and rating
plate used on all models (fig. 1) is located on the left door
pillar.
The vehicle identification number stamped on the plate
decodes into the information shown in Figure 2.
ENGINE NUMBER
The engine number indicates manufacturing plant, month
and day of manufacture, and transmission type. A typical
engine number would be F1210FA, which would breakdown
thus:
F—Manufacturing Plant (F-Flint, T-Tonawanda)
12—Month of manufacture (December)
10—Day of manufacture (tenth)
FA—Transmission and engine type
UNIT AND SERIAL NUMBER LOCATIONS
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.
CHEVY V A N SHOP M A NU AL

GENERAL INFORMATION 0-2
Q CHEVROLET MOTOR DIVISION Q
^ GENERAL MOTORS CORPORATION ^
WARRANTY MAY BE VOIDED IF WEIGHT
EXCEEDS ANY OF THE RATINGS SHOWN.
GROSS VEHICLE WEIGHT INCLUDES WEIGHT OF
BASE TRUCK, ALL ADDED EQUIPMENT, DRIVER
AND PASSENGERS, AND ALL PROPERTY LOADED
INTO TRUCK.
*REFER TO OWNER’S MANUAL FOR EQUIP
MENT REQUIRED FOR INTERMEDIATE OR
MAXIMUM GVW RATINGS, AND FOR OTHER
LOADING INFORMATION, INCLUDING TIRE
INFLATION. RATING IN POUNDS
AS M A N U - * MAXIMUM
FACTURED CAPABILITY
GROSS VEHICLE WEIGHT
FOR THIS VEHICLE
MAXIMUM FRONT END
WEIGHT AT GROUND
MAXIMUM REAR END
WEIGHT AT GROUND
VEHICLE IDENTIFICATION NO.
C r-----------------1 o
Axles
• Rear Axle erial Number Located at the Bottom Flange
of Carrier Housing.
• Rear Axle (Except Half Ton) Forward Upper urface of
Carrier.
Tr nsmissions
• 3- peed Transmission Unit Number Located on Lower
Left ide of Case Adjacent to Rear of Cover.
• Powerglide and Turbo Hydra-Matic 350 Transmission
Unit Number Located on Right Rear Vertical urface of
Oil Pan.
Engines
• 6-Cylinder Engine Unit Number Located on Pad at Right
Hand ide of Cylinder Block at Rear of Distributor.
• 8-Cylinder Engine Unit Number Located on Pad at
Front, Right Hand ide of Cylinder Block.
Delcotrons
Delcotron Unit erial Number—Top of Rear Housing.
B tteries
Battery Code Number Located on Cell Cover Top of
Battery.
Fig. 1—Vehicle Identific tion Number nd R ting
Pl te Inform tion
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.
Always include the prefix in the number.
St rters
tarter erial Number and Production Date tamped on
Outer Case, Toward Rear.
SERVICE PARTS IDENTIFICATION PLATE
The Chevrolet Truck ervice Parts Identification Plate (fig.
3) is provided on all Truck models. It is located on an inner
body panel to the right of the rear door. The plate lists the
vehicle serial number, wheelbase, and all Production options or
pecial Equipment on the vehicle when it was shipped from
the factory including paint information. ALWAY REFER TO
THI INFORMATION WHEN ORDERING PART .
SERVICE PARTS IDENTIFICATION
V.I.N.—VEHICLE IDENTIFICATION NUMBER
N O T E : T H E S P E C IA L E Q U IPM E N T L IS TE D B ELO W H A S BE EN IN S TA L L ED ON
T H I S V E H I C L E . F O R P R O P E R I D E N T I F IC A T IO N O F R E P L A C E M E N T
P A R T S B E S U R E T O S P E C IFY T HE A P P LIC A B L E O P TIO N N U M B ER S-
DIVISION
C = CHEVROLET
ENGINE
DESIGNATION
S=L6 ENG
E=V8 ENG
CHASSIS TYPE
MODEL TYPE
5-P nel
6-Suburb n
MODEL YEAR
2=1972 FOR ALL
SERIES
SEQUENTIAL NUMBER
ASSEMBLY
A-L kewood
B-B lHmore
C-Southg te
D-Dor ville
F-Flint
PLANT
V-GM Truck-Ponti c
R-Arlinglon
S-St. Louis
T-T rrytown
U-Lordstown
G-Fr mingh m W-Willow Run
J-J nesville Y-Wilmington
K-Leeds Z-Fremont
L-V n Nuys 1-Osh w
N-Norwood 2-Ste. Therese IMPORTANT: RETAIN THIS PLATE AS A PERMANENT RECORD
Fig. 2—Vehicle Identific tion Number Fig. 3—Service P rts Identific tion Pl te
C HE VY VA N SHOP M A NU AL

GENERAL INFORMATION 0-3
KEYS AND LOCKS
Two keys are provided with each vehicle. The keys operate
the ignition switch and door locks.
EMERGENCY STARTING
• Never tow the vehicle to start because the surge forward
when the engine starts could cause a collision with the
tow vehicle.
• Engines in vehicles with automatic transmissions cannot
be started by pushing the vehicle.
• To start the vehicle when the Energizer (battery) is
discharged, use a single auxiliary battery or Energizer of
the s me nomin l volt ge as the discharged battery, with
suitable jumper cables.
• Make connections as set forth below under “Jump
tarting With Auxiliary (Booster) Battery” to lessen the
chance of personal injury or property damage.
CAUTIO N: Never expose b ttery to open fl me or
electric sp rk—b ttery ction gener tes hydrogen
g s which is fl mm ble nd explosive. Don't llow
b ttery fluid to cont ct skin, eyes, f brics, or
p inted surf ces—fluid is sulfuric cid solution
which could c use serious person l injury or
property d m ge. We r eye protection when work
ing with b ttery.
Jump St rting With Auxili ry
(Booster) B ttery
Both booster and discharged battery should be treated
carefully when using jumper cables. Following ex ctly the
procedure outlined below, being careful not to cause sparks:
1. et parking brake and place automatic transmission in
Fig. 4—Booster B ttery C ble Ground Connection.
“PARK” (neutral for manual transmission). Turn off
lights, heater and other electrical loads.
2. Remove vent caps from both the booster and the
discharged batteries. Lay a cloth over the open vent wells
of each battery. These two actions help reduce the
explosion hazard always present in either battery when
connecting “live” booster batteries to “dead” batteries.
3. Attach one end of one jumper cable to the positive
terminal of the booster b ttery (identified by a red color,
“+” or “P” on the battery case, post or clamp) and the
other end of same cable to positive terminal of dis
ch rged b ttery. Do NOT permit vehicles to touch each
other, as this could establish a ground connection and
counteract the benefits of this procedure.
4. Attach one end of the remaining negative (—) cable to
the negative terminal (black color, ” or “N”) of the
booster b ttery, and the other end to the engine lift
bracket on 6 cylinder models and the delcotron m ount
ing bracket on V8 models (see Figure 4) of your 1972
vehicle (do not connect directly to negative post of dead
battery)—taking care that clamps from one cable do not
inadvertently touch the clamps on the other cable. Do
not lean over the battery when making this connection.
Reverse this sequence exactly when removing the jumper
cables. Re-install vent caps and throw cloths away as the
cloths may have corrosive acid on them.
CAUTIO N: Any procedure other th n the bove
could result in: (1) person l injury c used by
electrolyte squirting out the b ttery vents, (2)
person l injury or property d m ge due to b ttery
explosion, (3) d m ge to the ch rging system of the
booster vehicle or of the immobilized vehicle.
Do not ttempt to jump st rt vehicle h ving
frozen b ttery bec use the b ttery m y rupture or
explode. If frozen b ttery is suspected, ex mine
ll fill vents on the b ttery. If ice c n be seen, or if
the electrolyte fluid c nnot be seen, do not ttempt
to st rt with jumper c bles s long s the b ttery
rem ins frozen.
PUSH STARTING
If your vehicle is equipped with a manual transmission, it
can be started in an emergency by pushing. When being pushed
to start the engine, turn off all unnecessary electrical loads,
turn ignition to “ON,” depress the clutch pedal and place the
shift lever in high gear. Release the clutch pedal when speed
reaches 10 to 15 miles per hour. Bumpers and other parts
contacted by the pushing vehicle should be protected from
damage during pushing. Never tow the vehicle to start.
TOWING
Normally your vehicle may be towed with all four wheels
on the ground for distances up to 50 miles at speeds of less
than 35 MPH. The engine should be off and the transmission
in neutral.
However, the rear wheels must be raised off the ground or
L-6 MODELS
V-8 MODELS
CHE VY VA N SHOP M A N UAL

GENERAL INFORMATION 0-4
the drive shaft disconnected when the transmission is not
operating properly or when a speed of 35 MPH or distance of
50 miles will be exceeded.
CAUTIO N: If truck is towed on its front wheels
only, the steering wheel must be secured with the
wheels in str ight he d position.
ENGINE—VEHICLE AVAILABILITY
ehicle Displacement Cyl. Comp. Ratio Spark Plugs
GS 10-20-30 250 Cu. In. L6 8.5:1 R 4 6 -T
GE 10 307 Cu. In. 8 8.0:1 R 4 4 -T
GE 20-30 350 Cu. In. 8 9.0:1 R 4 4 -T
LOAD CAPACITY CHART INTERPRETATION
The first column of the Load Capacity Chart shows the
basic model series.
The next column reflects the wheelbases available within
each series.
The third column shows the Gross Vehicle Weight (GVW)
ratings applicable to each series vehicle. GVW means the
maximum design weight of the vehicle itself and all equipment
added to the vehicle after it has left the factory, the driver
weight and occupant weight and everything that is loaded into
or onto the vehicle.
F o llo w in g th e GVW colum ns are the minimum
recommended tires to qualify the vehicle for each GVW rating.
The tire pressures listed in the column adjacent to the tire
sizes in the chart are the minimum required tire pressures for
maximum permissible loads.
The letters “B.E.” under the Front and Rear Axle and
pring columns indicate that base equipment is satisfactory to
qualify the vehicle for any given GVW rating. When the letters
“RPO” denoting Regular Production Option, followed by a
number appears in these columns (example RPO G50), the
vehicle must be equipped with the extra cost equipment
specified by the RPO to qualify the vehicle for the given GVW
rating.
The ratings shown under the columns identified “Maximum
Front End Weight at Ground” and “Maximum Rear End
Weight at Ground” indicates the maximum permissible loading
or weight at the ground regardless of spring or axle capacity
ratings. These ratings are developed on the basis of the
minimum component capability be it axles, springs or tires.
In loading the vehicle, the combined front and rear end
weights at the ground must not exceed the GVW specified for
the vehicle as manufactured.
In trailer hauling applications, the vehicle rear end weight at
the ground with trailer attached must not exceed the
“Maximum Rear End Weight at Ground” rating of the vehicle.
A typical example of a Truck in a loaded condition is
shown in Figure 5. Note that the axle or GVW capabilities are
not exceeded.
Fig. 5—Typic l Vehicle Lo ded Condition
LOADED-MAXIMUM GVW: 4500 LBS.
FR ONT A XL E C APA CIT Y: 2500 L BS. REAR A X LE CA PAC IT Y: 2300 LBS.
Front Curb 1959 lbs. Re r Curb 1562 lbs.
Front C rgo Re r C rgo
Lo d 300 lbs. Lo d 650 lbs.
2259 lbs. 2212 lbs.
TOTAL WEIGHT AT GROUND: 4471 lbs.
C HE VY V AN SHOP M A NU AL

LOAD CAPACITY CHART
LOAD CAPACITY CHART FOR 1972 CHEVROLET SERIES G10, G20, G30 CHEVY VAN
GENERAL INFORMATION 0-5
1972
MODELS WHEEL
BASE
GROSS
VEHICLE
WEIGHT
RATING
(POUNDS)
MAXIMUM
LOAD
CAPACITY c
MINIMUM MANDATORY EQUIPMENT FOR GVW RATING
FRONT
TIRES
FRONT
TIRE
PRES
SURE REAR
TIRES
REAR
TIRE
PRES
SURE FRONT AXLE FRONT
SPRINGS
GROSS AXLE
WEIGHT
RATIN G-
FRONT REAR
AXLE REAR
SPRINGS
GROSS AXLE
WEIGHT
RATING
REAR
GS-GE10
(05 models)
110
4500 990 E 8-14B
or .00-14C e 32
... .....
E 8-14B
or .00-14C e 32
45 BE BE BE BE 2548
2620 BE BE BE
BE 2300
2300
5000 a 1440 F 8-14B
or .00-14D 32
60 F 8-14B or .00-14D 32
60 BE
BE RPO F60
RPO F60 2 30
3000 BE BE RPO G50
RPO G50 2 30
3100
125
4600 920 F 8-14B
or .00-14C e 32 45 F 8-14B
or .00-14C e 32 40 BE BE BE BE 2620
2620 BE
BE BE
BE 2300
2300
5100 a 1380 F 8-14B
or .00-14D 32 60 F 8-14B
or .00-14D 32 60 BE BE RPO F60
RPO F60 2 30 3000 BE BE RPO G50
RPO G50 2 30
3100
GS-GE20
(05 models) 110 5500 1890 G 8-15B 32 G 8-15B 32 BE BE 2948 BE BE 2948
6000 2360 H 8-15B 32 H 8-15B 32 BE BE 3200 BE BE 3200
125 5600 1830 G 8-15B 32 G 8-15B 32 BE BE 2948 BE BE 2948
6000 2230 H 8-15B 32 H 8-15B 32 BE BE 3200 BE BE 3200
GS-GE30
(05 models) 110 6100 2210 8.00-16.5C 40 8.00-16.5C 45 BE BE 3200 BE BE 3460
6 00 2800 8. 5-16.5C 35 8. 5-16.5C 45 BE BE 3200 BE BE 3980
600 3660 8. 5-16.5D 35 8. 5-16.5D 60 BE BE 3200 BE RPO G50 4 00
GE30
(05 models) 110 8100 b 4180 8. 5-16.5E 35 8. 5-16.5E 5 BE BE 3200 BE RPO G50 5360
GS-GE30
(05 Models) 125 6200 2150 8.00-16.5C 40 8.00-16.5C 45 BE BE 3200 BE BE 3460
6900 2840 8. 5-16.5C 35 8. 5-16.5C 45 BE BE 3200 BE BE 3980
800 3 00 8. 5-16.5D 35 8. 5 16.5D 60 BE BE 3200 BE RPO G50 4 00
GE30
(05 models) 125 8300 b 4010 8. 5-16.5E 35 8. 5-16.5E 5 BE BE 3200 BE RPO G50 5360
LOAD CAPACITY CHART FOR 1972 CHEVROLET SERIES G10, G20, G30 SPORTVAN AND BEAUVILLE SPORTVAN
1972
MODELS WHEEL
BASE
GROSS
VEHICLE
WEIGHT
RATING
(POUNDS)
MAXIMUM
LOAD
CAPACITY c
MINIMUM MANDATORY EQUIPMENT FOR GVW RATING
FRONT
TIRES
FRONT
TIRE
PRES
SURE REAR
TIRES
REAR
TIRE
PRES
SURE FRONT
AXLE FRONT
SPRINGS
GROSS AXLE
WEIGHT
RATING-
FRONT REAR AXLE REAR
SPRINGS
GROSS AXLE
WEIGHT
RATING-
REAR
GS-GE10
(06, 36
Models)
110 5200 1380 F 8-14B 32 F 8-14B 32 BE BE 2 30 BE BE 2 30
5400 1580 G 8-14B 32 G 8-14B 32 BE BE 2948 BE BE 2948
125 5400 1410 G 8-14B 32 G 8-14B 32 BE BE 2948 BE BE 2948
GS-GE20
(06, 36
models)
110 5 00 1830 G 8-15B 32 G 8-15B 32 BE BE 2948 BE BE 2948
125 5800 1 0 G 8-15B 32 G 8-15B 32 BE BE 2948 BE BE 2948
110 6000 2130 H 8-15B 32 H 8-15B 32 BE BE 3200 BE BE 3200
125 6200 2160 H 8-15B 32 H 8-15B 32 BE BE 3200 BE BE 3200
GS-GE30
(06, 36
models) 125
6600 2310 8.00-16.5C 40 8.00-16.5C 45 BE BE 3200 BE BE 3460
000 2 00 8. 5-16.5C 35 8. 5-16.5C 45 BE BE 3200 BE BE 3980
300 2980 8. 5-16.5D 35 8. 5-16.5D 50 BE BE 3200 BE BE 4200
600 d 3260 8. 5-16.5D 35 8. 5-16.5D 60 BE BE 3200 BE RPO G50d 4 00
GE30
(06, 36
models) 125 8300 bd 3 0 8. 5-16.5E 35 8. 5-16.5E 5 BE BE 3200 BE RPO G50d 5360
Refer to the Gross Vehicle Weight Rating plate on the vehicle. Gross Axle Weight Rating-Front, and Gross Axle Weight Rating-Rear on this chart are based upon
component minimum capacity of axles, springs, or tires,
a RPO J 0 Power Brakes required,
b RPO F59 Front Stabilizer Bar required.
c "Maximum Load Capacity" represents the maximum total weight of people, luggage, cargo and equipment that may be added to a standard vehicle equipped with a base six
cylinder engine. This "Maximum Load Capacity" rating must be reduced by the additional weight of a V8 engine (if a V8 engine is used), and by the weight of any
other optional equipment,
d 600 and 8300 GVW and RPO G50 rear springs for 06, 36 models are not to be promoted,
e Optional tires available as RPO equipment.
CHEV Y VAN SHOP M A N UAL

LUBRICATION 0-6
LUBRICATION
INDEX
Page
Engine
Oil and Filter Recom m endations
....................................... 0-6
Drive B elts.................................................................................0-7
Positive Crankcase V entilation ............................................ 0-7
Air Injection Reactor ystem ............................................ 0-7
Controlled Combustion y stem ..........................................0-7
GM Evaporation Control ystem ....................................... 0-7
Manifold Heat Control V alve...............................................0-7
Air Cleaner .............................................................................. 0-7
Fuel F ilte r.................................................................................0-7
D istributor.................................................................................0-7
G overnor................................................................................... 0-7
Accelerator Linkage................................................................0-8
Automatic Transmission Fluid Recom m endations ............ 0-8
Manual Transmission ..................................................................0-8
Transmission hift Linkage ......................................................0-8
Clutch .............................................................................................0-8
Rear A x le........................................................................................0-8
tandard ................................................................................... 0-8
The tim e or mileage intervals for lubrication and
maintenance services outlined in this section are intended as a
guide for establishing regular maintenance and lubrication
Page
Positraction .............................................................................. 0-8
Propeller haft lip Joints ........................................................ 0-8
Universal Joints ............................................................................0-8
Wheel Bearings...............................................................................0-8
Front R ear.................................................................................0-8
R e ar............................................................................................. 0-9
Brake Master Cylinder ................................................................0-9
Brake and Clutch Pedal prings ...............................................0-9
Parking B rake.................................................................................0-9
teering ...........................................................................................0-9
Manual teering G ear.............................................................0-9
Power teering ystem ........................................................ 0-9
teering Linkage and uspension ....................................... 0-9
Hood Latch and Hood H in g e....................................................0-9
Body Lubrication
......................................................................... 0-11
peedometer A dapter..................................................................0-11
Extended Vehicle torage ........................................................ 0-11
Lubrication Diagram ..................................................................0-10
Vehicle Lifting P oints..................................................................0-11
periods. ustained heavy duty and high speed operation or
operation under adverse conditions may require more frequent
servicing.
ENGINE
OIL AND FILTER RECOMMENDATIONS
The letter designation “ E” has been established to corre
spond with the requirements of GM 6041-M as revised. “ E”
engine oils will be better quality and perform better than those
identified with “ A” through “ D” designations and are
recommended for all Chevrolet light-duty gasoline trucks
regardless of model year and previous engine oil quality
recommendations.
OIL CHANGE PERIOD
• Use only E engine oil ( E oils meet quality standard
GM 6041-M).
• Change oil each 4 months or 6,000 miles. If more than
6,000 miles are driven in a 4-month period, change oil
each 6,000 miles.
• Change oil each 2 months or 3,000 miles, whichever
occurs first, under the following conditions:
—driving in dusty conditions
—trailer pulling
—extensive idling
— hort-trip operation at freezing temperatures (engine
not thoroughly warmed-up).
• Operation in dust storms may require an immediate oil
change.
• Replace the oil filter at the first oil change, and every
second oil change thereafter. AC oil filters provide
maximum engine protection.
The above recommendations apply to the first change as
well as subsequent oil changes. The oil change interval for the
Chevrolet engine is based on the use of E oils and quality oil
filters. Oil change intervals longer than those listed above will
seriously reduce engine life and may affect Chevrolet’s obliga
tion under the provisions of the New Vehicle Warranty.
A high quality E oil was installed in the engine at the
factory. It is not necessary to change this factory-installed oil
prior to the recommended normal change period. However,
check the oil level more frequently during the break-in period
since higher oil consumption is normal until the piston rings
become sealed.
NOTE: Non-detergent nd other low qu lity oils
re specific lly not recommended.
Oil Filter Type nd C p city
Throwaway type, 1 quart U. . measure, .75 quart Imperial
measure.
250 cu. in., AC Type PF-25. 307 cu. in., 350 cu. in., AC
Type PF 35.
Cr nkc se C p city (Does not include filter)
4 quarts U. . measure, 3.25 quarts Imperial measure.
CHEV Y VA N SHOP M A NU AL

LUBRICATION 0-7
Recommended Viscosity
elect the proper oil viscosity from the following chart:
RECOMMENDED SAE VISCOSITY NUMBER
E g ME
10W, 5W-30, 10W-30, 10W-40
-3 0 - 2 0 0 20 40 60 80 100
TEMPERATURE RANGE ANTICIPATED BEFORE NEXT OIL CHANGE, °F.
NOTE: SAE 5W-20 oils re not recommended for
sust ined high-speed driving.
SAE 30 oils m y be used t temper tures bove 40°
F.
The proper oil viscosity helps assure good cold and hot
starting.
Checking Oil Level — The engine oil should be maintained at
proper level. The best time to check it is before operating the
engine or as the last step in a fuel stop. This will allow the oil
accumulation in the engine to drain back in the crankcase. To
check the level, remove the oil gauge rod (dip stick), wipe it
clean and reinsert it firmly for an accurate reading. The oil
gauge rod is marked “FULL” and “ADD OIL” . If the oil is at
or below the “ADD” mark on the dipstick, oil should be
added as necessary. The oil level should be maintained in the
safety margin, neither going above the “ FULL” line nor below
“ADD OIL” line.
NOTE: The oil g uge rod is lso m rked either,
"Use SE Engine Oil" or, "Use GM 6041-M Qu lity
MS Oil", s reminder to use only SE oils.
Supplement l Engine Oil Additives
The regular use of supplemental additives is specifically not
recommended and will increase operating costs. However,
supplemental additives are available that can effectively and
economically solve certain specific problems without causing
other difficulties. For example, if higher detergency is required
to reduce varnish and sludge deposits resulting from some
unusual operational difficulty, a thoroughly tested and
approved additive—“ Engine Oil upplement” —is available.
DRIVE BELTS
Drive belts should be checked every 6,000 miles or 4
months for proper tension. A loose belt will affect water pump
and generator operation.
POSITIVE CRANKCASE VENTILATION VALVE
Every 24,000 miles or 24 months the valve should be
replaced. Connecting hoses, fittings and flame arrestor should
be cleaned. At every oil change the system should be tested for
proper function and serviced, if necessary.
AIR INJECTION REACTOR SYSTEM (A.I.R.)
CONTROLLED COMBUSTION SYSTEM (C.C.S.)
The Air Injection Reactor system should have the drive belt
inspected for wear and tension every 12 months or 12,000
miles, whichever occurs first. In addition, complete effective
ness of either system, as well as full power and performance,
depends upon idle speed, ignition timing, and idle fuel mixture
being set according to specification. A quality tune-up which
includes these adjustments should be performed periodically
to assure normal engine efficiency, operation and per
formance.
GIVI EVAPORATION CONTROL SYSTEM
Every 24 months or 24,000 miles (more often under dusty
conditions) the filter in the base of the canister must be
replaced and the canister inspected.
MANIFOLD HEAT CONTROL VALVE
Every 6,000 miles or 4 months, check valve for freedom of
operation. If valve shaft is sticking, free it up with GM
Manifold Heat Control olvent or its equivalent.
AIR CLEANER
NOTE: Under prolonged dusty driving conditions,
it is recommended th t these oper tions be
performed more often.
Oil Wetted P per Element Type—
L-6 engine, replace every 12,000 miles; V-8 engine, every
12.000 miles, inspect element for dust leaks, holes or other
damage. Replace if necessary. If satisfactory, rotate element
180° from originally installed position. Replace at 24,000
miles. Element must not be washed, oiled, tapped or cleaned
with an air hose.
Cr nkc se Ventil tion Filter (Loc ted Within
Air Cle ner)
If so equipped, inspect at every oil change and replace if
necessary. Replace at least every 24,000 miles; more often
under dusty driving conditions.
FUEL FILTER
Replace filter element located in carburetor inlet every 12
months or 12,000 miles whichever occurs first, or, if an in-line
filter is also used, every 24,000 miles.
Replace in-line filter every 24,000 miles.
DISTRIBUTOR
Remove distributor cap and rotate lubricator 1/2 turn at
12.000 mile intervals. Replace at 24,000 mile intervals.
GOVERNOR
The attaching bolts should be kept tight, the optionally
available governor should be kept clean externally and the
filter element should be replaced every 12,000 miles.
CHEVY V A N SHOP MA NUA L

LUBRICATION 0-8
ACCELERATOR LINKAGE
Lubricate with engine oil every 12,000 miles as follows:
1. On V8 engine, lubricate the ball stud at the carburetor
lever.
2. On L6 engine, lubricate the two ball studs at the
carburetor lever and lubricate the lever mounting stud.
Do not lubricate the accelerator cable.
AUTOMATIC TRANSMISSION FLUID
RECOMMENDATIONS
General Motors DEXTRON® Automatic Transmission
Fluid, which has been especially formulated and tested for use
in the automatic transmission is recommended. Other auto
m atic tran sm issio n fluids identified with the mark
DEXTRON® are also recommended.
Check the fluid level at each engine oil change period. To
make an accurate fluid level check:
1. Drive vehicle several miles, making frequent starts and
stops, to bring transmission up to normal operating
temperature (approximately 180-190° F).
2. Park vehicle on a level surface.
3. Place selector level in “Park” and leave engine running.
4. Remove dipstick and wipe clean.
5. Reinsert dipstick until cap seats.
6. Remove dipstick and note reading.
If oil level is at or below the ADD mark on the dipstick, oil
should be added as necessary. One pint raises the level from
ADD to FULL. Do not overfill.
Under normal driving conditions, the transmission fluid
should be changed every 24,000 miles. If the vehicle is driven
extensively in heavy city traffic during hot weather, or is used
to pull a trailer, change fluid every 12,000 miles. Likewise,
operators of trucks in commercial use where the engine idles
for long periods, should change fluid every 12,000 miles.
To Ch nge Turbo Hydr -M tic 350 fluid, remove fluid from
the transmission sump, add approximately 2-1/2 qts. U. .
measure (2 qts. Imperial measure) for the Turbo Hydra-Matic
350 of fresh fluid, to return level to proper mark on the
dipstick.
MANUAL TRANSMISSION
3- peed and 4- peed—every 6,000 miles or 4 months—
check at operating temperature and fill as necessary to level of
filler plug hole with AE 80 or AE 90 GL-5 gear lubricant.
Where ambient temperatures below freezing (+32°F.) are
expected, use only AE 80 GL-5 Gear Lubricant. AE 90 Gear
Lubricant should be used only where ambient temperatures
are continuously above +32°F.
TRANSMISSION SHIFT LINKAGE
(MANUAL AND AUTOMATIC)
Every 6,000 miles or 4 months—lubricate shift linkage and,
on Manual transmission floor control, lever contacting faces
with water resistant EP chassis lubricant which meets GM
pecification GM 6031M.
CLUTCH
The clutch pedal free travel should be checked at regular
intervals.
Lubricate the clutch cross-shaft at fitting (on eries 10
Forward Control models also lubricate the clutch linkage idler
lever at fitting) every 6,000 miles or 4 months with water
resistant EP chassis lubricant which meets General Motors
pecification #GM-6031M.
REAR AXLES
St nd rd
Every 4 months or 6,000 miles, whichever occurs first,
check lubricant level and add lubricant, if necessary, to fill to
level of filler plug hole. Use GL-5 Gear Lubricant as shown in
the following table.
Outside Temper ture Viscosity Lubric nt To Be Used
BELOW 10°F SAE 80
UP TO 100°F SAE 90
ABOVE 100° F
CO NSISTENTLY SAE 140
On 20 or 30 eries trucks, drain lubricant every 24,000
miles. If vehicle is operated in exceptionally heavy work or at
continuous high speeds, the lubricant should be changed every
12,000 miles. It may be necessary to change lubricant more
often if vehicle is used off road in dusty areas.
Positr ction
ame intervals as standard axle but use only the special
Positraction lubricant available at your authorized dealer.
PROPELLER SHAFT SLIP JOINTS
Propeller shaft slip joints should be lubricated every 6,000
miles or 4 months with water resistant EP chassis lubricant
which meets General Motors pecification GM 6031M.
UNIVERSAL JOINTS
All universal joints are the needle bearing type. Lubricate
those universal joints (depending on truck model) equipped
with lube fittings every 6,000 miles or 4 months with water
resistant EP chassis lubricant which meets General Motors
pecification GM 6031M. More frequent lubes may be
required on heavy duty or “Off the Road” operations.
WHEEL BEARINGS
Front
NOTE: Use wheel be ring lubric nt GM P rt No.
1051344 or equiv lent. This is premium high
melting point lubric nt which meets ll require
ments of Gener l Motors Specific tion GM 6031M.
CHEV Y V AN SHOP M A NU AL

LUBRICATION 0-9
Due to the weight of the tire and wheel assembly it is
recommended that they be removed from hub before lubricat
ing bearings to prevent damage to oil seal. Then remove the
front wheel hub to lubricate the bearings. The bearings should
be thoroughly cleaned before repacking with lubricant.
Front wheels are equipped with tapered roller bearings on
all trucks. Wheel bearings should be lubricated every 24,000
miles. Do not mix wheel bearing lubricants.
CAUTIO N: "Long Fibre" type gre ses should not
be used on roller be ring front wheels.
Re r
The rear wheel bearings receive their lubrication from the
rear axle. When installing bearings which have been cleaned,
prelube with wheel bearing grease.
BRAKE MASTER CYLINDER
Check master cylinder fluid level in both reservoirs every
6,000 miles or 4 months. If the fluid is low in the reservoir, it
should be filled to a point about 1/4” from the top rear of
each reservoir with Delco upreme No. 11 Hydraulic Brake
Fluid.
BRAKE AND CLUTCH PEDAL SPRINGS
Lubricate brake and clutch pedal springs every 6,000 miles
or 4 months with engine oil for all models.
PARKING BRAKE
Every 6,000 miles or 4 months clean and lubricate all
parking brake pivot points with water resistant EP chassis
lubricant which meets General Motors pecification GM
6031M.
STEERING
MANUAL STEERING GEAR
The steering gear is factory-filled with steering gear lub
ricant. easonal change of this lubricant should not be
performed and the housing should not be drained—no lubric 
tion is required for the life of the steering ge r.
Every 36,000 miles, the gear should be inspected for seal
leakage (actual solid grease—not just oily film). If a seal is
replaced or the gear is overhauled, the gear housing should be
refilled with #1051052 (13 oz. container) teering Gear
Lubricant which meets GM pecification GM 4673M, or its
equivalent.
NOTE: Do not use EP Ch ssis Lube, which meets
GM Specific tion GM 6031M, to lubric te the ge r.
DO NOT O VE R -FILL the ge r housing.
NOTE: Lubric te intermedi te steering sh ft with
w ter resist nt EP ch ssis lubric nt which meets
Gener l Motors Specific tion #GM 6031M every
6,000 miles or 4 months on P-10 models only.
POWER STEERING SYSTEM
Check the fluid level in the pump reservoir at each oil
change period. Add GM Power teering Fluid as necessary to
bring level to proper range on filler cap indicator depending
upon fluid temperature.
If at operating temperature (approximately 150°F—hot to
the touch), fluid should be between “HOT” and “COLD”
marks.
If at room temperature (approximately 70° F), fluid should
be between “ADD” and “COLD” marks. Use DEXRON®
Automatic Transmission Fluid if GM Power teering Fluid is
not available. Fluid does not require periodic changing.
STEERING LINKAGE AND SUSPENSION
Maintain correct front end alignment to provide easy
steering, longer tire life, and driving stability.
Check control arm bushings and ball joints for wear.
Lubricate tie rods, upper and lower control arms, and ball
joints at fittings with water resistant EP chassis lubricant
which meets General Motors pecification GM 6031M every
6,000 miles or 4 months.
NOTE: B ll joints must be t +10°F. or more
before lubric ting.
Keep spring to axle U bolts and shackle bolts properly
tightened (see pecifications ection for torque recommenda
tions). Check U bolt nuts after the first 1,000 miles of
operation if the U bolt or U bolt nuts are changed in service.
HOOD LATCH AND HOOD HINGE
Every 6,000 miles or 4 months, whichever occurs first,
lubricate hood latch assembly and hood hinge assembly as
follows:
1. Wipe off any accumulation of dirt or contamination on
latch parts.
2. Apply Lubriplate or equivalent to latch pilot bolts and
latch locking plate.
3. Apply light engine oil to all pivot points in release
mechanism, as well as primary and secondary latch
mechanisms.
4. Lubricate hood hinges.
5. Make hood hinge and latch mechanism functional check
to assure the assembly is working correctly.
CHEV Y VA N SHOP M AN U AL

LUBRICATION 0-10
No. Lubrication Points Lubrication Period Type of Lubrication Quantity Remarks
1 Control Arm Bushings and
Ball Joints 6,000 Miles Chassis Lubricant 12 places as required
2Tie Rod Ends 6,000 Miles Chassis Lubricant 4 places as required 2 fittings each side
4 Wheel Bearings 30,000 Miles Whl. Brg. Lubricant 2 places as required
5 Steering Gear 36,000 Miles
Clutch Cross-Shaft 6,000 Miles Chassis Lubricant As required
8 Trans. Control Shaft 6,000 Miles Chassis Lubricant As required
9Air Cleaner-Elem ent 12,000 Miles Replace L-6, Rotate
-8, Replace -8 at
24,000 miles.
10 Distributor-L-6, -8 12,000 Miles Replace Cam
Lubricator*
11 Transmission-Synchromesh
—Automatic 6.000 Miles 6.000 Miles GL-5 Dexron® or Equivalent As required
As required See Lubrication Section See Lubrication Section
12 Rear Axle 6,000 Miles GL-5 As required See Lubrication Section
13 Oil Filter Every Second
Oil Change
14 Battery 5,000 Miles Engine Oil Oil Terminals and
Felt Washers
15 Brake Master Cylinder 6,000 Miles Delco Supreme
No. 11 or Equivalent As required Check-A dd fluid when
necessary
16 Parking Brake Linkage 6,000 Miles Chassis Lubricant Lubricate Linkage
and Cables
♦Replace Points and Lubricator at 24,000 Mile Intervals.
CHEV Y VAN SHOP M ANU AL.

LUBRICATION 0-11
BODY LUBRICATION
Normal use of a truck causes metal-to-metal movement at
certain points in the cab or body. Noise, wear and improper
operation at these points will result when a protective film of
lubricant is not provided.
For exposed surfaces, such as door checks, door lock bolts,
lock striker plates, dovetail bumper wedges, etc., apply a thin
film of light engine oil.
Where oil holes are provided in body parts a dripless oil can
be safely used, but any lubricant should be used sparingly, and
after application all excess should be carefully wiped off.
The seat adjusters and seat track, ordinarily overlooked,
should be lubricated with water resistant EP chassis lubricant
which meets General Motors pecification GM 6031M.
There are other points on bodies which may occasionally
require lubrication and which are difficult to service. Window
regulators and controls are confined in the space between the
upholstery and the outside door panel. Easy access to the
working parts may be made by removing the trim. Door
weatherstrips and rubber hood bumpers should be lightly
coated with a rubber lubricant.
SPEEDOMETER ADAPTER
On vehicles so equipped, lubricate adapter at fitting with
water resistant EP chassis grease which meets General Motors
pecification #GM 6031M every 6,000 miles.
EXTENDED VEHICLE STORAGE
If you plan to store your truck over an extended period of
time, certain steps should be taken to give it maximum
protection. It is recommended that you write the Chevrolet
Motor Division, General Motors Corporation, Owner Relations
Dept., Detroit, Michigan 48202, for detailed instructions on
how to prepare your truck for storage.
Fig. 8—Vehicle Lifting Points
CHEVY VA N SHOP MA NUA L

SECTION 1A
HEATER AND AIR CONDITIONING
CONTENTS OF THIS SECTION
tandard H e a ter ......................................................................... 1A-1
Auxiliary H eater......................................................................... 1A-6
Air Conditioning .......................................................................1A-9
STANDARD HEATER
INDEX
Page Page
General Description ....................................................
............ I A-! Left Distributor Duct
........................... .......................1A-4
Controls.....................................................................
............ 1A-2 Defroster D u ct.......................................... ........................... 1A -4
Component Replacement and R epair....................
............ 1A-2 Control Assembly .................................. ........................... 1A-5
Blower Assem bly.................................................... ............ 1A-2 Control C ables.......................................... ........................... 1A-5
Heater Core Case and Core Assembly ............ ............ 1A-2 Blower w itch ..........................................
........................... 1A-6
Heater H o se s...........................................................
............ 1A-3 R esisto r......................................................
........................... 1 A-6
Center Distributor D u c t .......................................
............ 1A-3
GENERAL DESCRIPTION
The heater components are mounted to the right side of the the dash while the heater case, core, ducting and controls are
dash panel. The blower motor is located on the forward side of located in the passenger compartment.
DASH DEFROSTER AIR DOOR CORE BLOWER
Fig. 1—He ter Airflow Schem tic
CHEVY VA N SHOP M AN UAL

HEATER 1A-2
The heater operates on “outside air” only, with the blower
receiving its airflow from the cowl vent plenum chamber.
Engine coolant flows through the heater core whenever the
engine is running. Heater output is controlled by varying the
amount and temperature of the air entering the passenger
compartment. A dash mounted, three lever control system is
used to p o sitio n th e “ D E F R O T ” , “ A IR” , and
“TEMPERATURE” doors and to actuate the three speed
blower switch.
CONTROLS
The controls are located in the instrument panel, just to the
right of the instrument cluster. In operation, three levers
control all heater operations (figs. 1 and 2).
HEAT Lever
When this lever is fully up, all incoming air is diverted
around the heater core. When fully down, all air is directed
through the core for maximum heating. The lever may be
moved anywhere between to provide the desired outlet tem
perature by blending both heated and unheated air.
AIR-FAN Lever
When this lever is fully up, no air passes through the
system. Moving the lever down approximately halfway, opens
the air door in the air distributor assembly. Moving the lever
the rest of the way down actuates the three speed (LOW-
MED-HI) blower switch.
DEFR Lever
When this lever is fully up, all incoming air is directed to
the floor outlets.
Moving the lever down, directs increasing amounts of air to
the defroster outlets until at the full down position, all of the
air is directed to the defroster outlets.
COMPONENT REPLACEMENT AND REPAIRS
BLOWER MOTOR (Fig. 3)
Repl cement
1. Disconnect the battery cables and remove the battery.
2. Disconnect the blower motor lead wire.
3. Remove the five blower m otor to dash screws and
remove the motor and wheel assembly. Pry gently on the
blower flange if the sealer acts as an adhesive.
4. Remove the blower wheel to motor shaft nut and
separate the wheel and motor assemblies.
5. To install a new motor, reverse teps 1-4,
NOTE: The following prec utions should be t ken
to ssure proper inst ll tion:
a. Assemble the blower wheel to the motor with the
open end of the wheel away from the blower
motor.
b. If the motor mounting flange to dash sealer has
hardened, or is not intact, remove the old sealer and
apply a new bead of sealer to the entire circum
ference of the mounting flange.
c. Check blower operation; blower wheel should ro
tate freely with no interference.
HEATER CORE CASE AND CORE
Repl cement (Fig. 4)
I . Disconnect the battery ground cable.
2. Place a clean pan under the vehicle and then disconnect
the heater core inlet and outlet hoses at the core
connections (see “Heater Hoses—Replacement” later in
this section). Quickly plug the heater hoses and support
them in a raised position. Allow the coolant in the heater
core to drain into the pan on the floor.
3. Disconnect the right hand air distributor hose from the
heater case and rotate it up out of the way.
CHEV Y VAN SHOP M A NU AL

HEATER 1A-3
4. Pry off the temperature door cable eyelet clip and then
remove the bowden cable attaching screw.
5. Remove the distributor duct to heater case screws and
pull the duct rearward out of the heater case retainer.
6. Remove the four heater case to dash screws and then
remove the heater case and core as an assembly. Tilt the
case assembly rearward at the top while lifting up until
the core tubes clear the dash openings.
7. Remove the core retaining strap screws and remove the
core.
8. To install a new core, reverse teps 1-7 above.
Heater hoses are routed from the water pump and thermo
stat housing to the core inlet and outlet pipes as shown in
Figure 5. Hoses are attached at each end with screw type
clamps.
Repl cement
The heater core can be easily damaged in the area of the
core tube attachment seams whenever undue force is exerted
on them. Whenever the heater core hoses do not readily come
off the tubes, the hoses should be cut just forward of the core
tubes. The portion of the hose remaining on the core tube
should then be split longitudinally. Once the hoses have been
split, they can be removed from the tubes w ithout damage to
the core.
CENTER DISTRIBUTOR DUCT
Repl cement (Fig. 6.)
1. Disconnect the battery ground cable.
2. Unsnap the engine cover front latches. Remove the two
cover to floorpan screws and remove the cover.
3. Remove the heater core case and core as an assembly (see
“Heater Core Case and Core .. Replacement”).
4. Disconnect the right hand heater outlet hose and the two
defroster hoses from the distributor duct.
5. Disconnect the air and defroster door cables by prying
off the eyelet clips and removing the cable attaching
screws.
HEATER HOSES
Fig. 5—He ter Hose Routings
CHE VY V A N SHOP M A N UA L

HEATER 1A-4
Fig. 6—Distributor Ducts
6. Pull the center distributor duct to the right and remove it
from the vehicle.
7. To install, reverse teps 1-6 above.
NOTE: Check c ble nd door oper tion; c bles
should be free from kinks or binding nd doors
should close properly. If c ble djustment is nec
ess ry, see "Bowden C ble—Adjustment."
LEFT DISTRIBUTOR DUCT
Repl cement (Fig. 6)
1. Disconnect the battery ground cable.
2. Unsnap the engine cover front latches. Remove the two
cover to floorpan screws and remove the cover.
3. Remove the duct bracket screw and remove the duct.
4. To install, reverse teps 1 -3.
NOTE: All three bowden c bles re routed under
the duct. It m y be necess ry to hold the c bles
down s the duct is being inst lled. Be sure the left
duct is fully inst lled over the center duct.
DEFROSTER OUTLETS AND HOSES
Repl cement (Fig. 7)
1. Disconnect the battery ground cable.
2. Unsnap the engine cover front latches. Remove the two
cover to floorpan screws and remove the cover.
3. Disconnect the defroster hose at both the center distribu
tor duct and instrument panel outlet and remove the
hose.
4. If the instrument panel outlets must be removed, reach
under the instrument panel and squeeze the outlet tabs
inward while pushing up. Remove the outlets from the
instrument panel.
5. If the outlets were removed, snap them in position in the
instrument panel.
6. Reinstall the defroster hoses following teps 1-3 in
reverse order.
Fig. 7—Defroster Outlets nd Hoses
CHEVY VA N SHOP M A N UAL
• 1 i . g

HEATER 1A-5
DEFROST
AIR
CABLETEMP
CABLE
Fig. 8—Control Assembly
CONTROL ASSEMBLY
Repl cement (Fig. 8)
1. Disconnect the battery ground cable.
2. Disconnect the blower switch wiring harness connector at
the lower side of the control.
3. Remove the two control to instrument panel mounting
screws and carefully lower the control far enough to gain
access to the bowden cable attachments.
CAUTION: C re should be t ken to prevent kink
ing the bowden c bles while lowering the control.
4. Disconnect the three bowden cables, the control illumi
nation bulb, and remove the control from the vehicle.
5. Remove the blower switch screws and remove the blower
switch.
6. To install, reverse teps 1-5 above.
NOTE: Be sure to reinst ll ll ground wires when
reinst lling the control to I.P. lower mounting
screw.
CONTROL CABLES
Repl cement (Fig. 9)
1. Disconnect the battery ground cable.
2. Unsnap the engine cover front latches. Remove the two
cover to floorpan screws and remove the cover.
3. Remove the left distributor duct attaching screw and
remove the duct.
4. Defroster C ble Only-Rem ove the radio speaker bracket
to dash panel (2) screws.
5. Pry off the cable eyelet clip at both the door and control
lever. Remove the cable attaching screw at both door and
control locations.
6. Attach a 4’ piece of wire to the door end of the cable.
Place protective tape around the cable mounting tab and
attached wire and carefully pull the cable from the
vehicle. Remove the tape and disconnect the 4’ piece of
wire.
NOTE: On defroster c bles, pull re rw rd slightly
on the r dio spe ker br cket to get cle r nce for
c ble remov l.
DEFROSTER
CABLE
VIEW A
WITHOUT RADIO WITH RADIO
Fig. 9-C ontrol C ble Routings
CH EVY VA N SHOP M A N UA L
A 1 A

HEATER 1 A-6
7. To install, attach the new cable to the 4 ’ piece of wire.
Tape the mounting tab and attached wire. Carefully pull
the new cable into position.
8. Reverse teps 1-5.
NOTE: If c ble djustment is required, see below.
Adjustment
1. Disconnect the battery ground cable.
2. Air nd Defroster Door C bles—Unsnap the engine cover
front latches. Remove the two cover to floorpan screws
and remove the engine cover.
3. Pry off the appropriate cable eyelet clip and disconnect
the cable from the door.
4. Remove the cable retaining screw.
5. While holding the cable with pliers, rotate the mounting
tab on the cable to lengthen or shorten the cable,
whichever is required.
NOTE: Do not pinch the c ble too tightly or
d m ge to the c ble could result.
6. Install the cable, reversing teps 1-4.
BLOWER SWITCH
Repl cement (Fig. 8)
1. Disconnect the battery ground cable.
2. Disconnect the blower switch wiring harness connector at
the switch.
3. Remove the two switch attaching screws and remove the
switch assembly.
4. To install a new switch, reverse teps 1-3 above.
NOTE: M ke cert in the switch rm bushing is in
pl ce nd th t the rm nd bushing eng ge the
slotted opening in the AIR-FA N lever when in
st lling the switch.
RESISTOR
Rep cement (Fig. 10)
1. Disconnect the wiring harness at the resistor connector.
2. Remove the two resistor to dash mounting screws and
remove the resistor.
3. To install a new resistor, reverse teps 1 and 2 above.
AUXILIARY HEATER
INDEX
Page Page
General D escription .................................................................. 1A-6 Component Replacement and R epairs .................................. 1A-7
C on tro ls................................................................................... 1A-6
GENERAL DESCRIPTION
An auxiliary heater is available as a dealer installed
accessory to provide additional heating capacity for the rear
most extremities of the Chevy Van and portvan models.
This unit operates entirely independent of the standard
heater and is regulated through its own controls at the
instrument panel.
This system consists of a separate core and fan unit
mounted either under the second seat or at the left side o f the
vehicle (Fig. 11). Heater hoses extend from the unit to the
front of the vehicle where they are connected to the standard
heater hoses with “tees” . An “on-off’ water valve is installed
in the heater core inlet line in the engine compartment. This
valve must be operated m anually-“on” for cold weather,
“o ff’ in warm weather. The purpose of the valve is to cut off
coolant flow to the auxiliary core during warm weather and
eliminate the radiant heat that would result.
CONTROLS
Two methods of control are employed with this system:
W ter V lve (Fig. 12)
When heat is desired, the water valve must be in the “on”
position (valve located in the engine compartment in the core
inlet line). During the summer months, this valve should be
placed in the “o f f ’ position.
CHEVY V A N SHOP MA NUA L

HEATER 1A-7
F n Switch (Fig. 13)
The two speed (HI-LOW) fan switch is located below the
left side of the instrument cluster. Pulling the switch knob out half-way places the fan on “HI” ; at the full out position, the
fan is on “LOW”.
COMPONENT REPLACEMENT AND REPAIRS
ince a detailed list of installation instructions is included
with the auxiliary heater unit, replacement procedures will not
be repeated in this section.
CAUTION: All Models—When repl cing he ter
hoses, m int in 1/2" minimum cle r nce between
the hose clip nd left upper control rm.
110" Wheelb se Models With Re r Se ts—Observe
the minimum cle r nces nd hose routings s shown
in Figure 14.
CHEVY V A N SHOP M A N UA L