
LUBRICATION 0-13
LUBRICATION
INDEX
Page
Engine Crankcase Oil . 0-13
Crankcase Capacities. . 0-13
Lubrication . ,
•
o-13
SAE Viscosity Oils 0-13
Types of Oils 0-14
Maintaining Oil Level 0-14
Oil and Filter Change Intervals 0-14
Oil.
. . ...:.. 0-14
Filter o-14
Crankcase Dilution . 0-14
Automatic Control Devices to Minimize
Crankcase Dilution 0-14
Crankcase Breather Cap 0-14
Crankcase Ventilation System 0-15
Valve Type 0-15
Fuel Filter 0-15
Air Cleaner . 0-15
Polyurethane Type 0-15
Oil Wetted Paper Element Type 0-15
Battery Terminal Washers 0-15
Page
Distributor 0-15
Rear Axle and 3-Speed and Overdrive
4-Speed Transmission 0-15
Recommended Lubricants 0-15
Multi-Purpose Gear Lubricants 0-15
Lubricant Additions 0-15
Lubricant Changes 0-15
Powerglide Transmission 0-15
Turbo Hydra-Matic 0-16
Front Wheel Bearings 0-16
Manual Steering Gear . . . . 0-16
Power Steering 0-16
Air Conditioning 0-16
Brake Master Cylinder. 0-16
Parking Brake 0-16
Clutch Cross-Shaft , 0-16
Chassis Lubrication 0-16
Lubrication Diagrams . . 0-19
Body Lubrication (Chevrolet, Chevelle, Chevy n, Camaro). 0-20
Body Lubrication Points (Corvette) . 0-21
The selection of the proper lubricant and its correct
application at regular intervals does much to increase the
life and operation of all moving parts of the vehicle.
Consequently, it is important that the correct grade of
oil or grease, as noted in the following pages, be used.
ENGINE CRANKCASE OIL
Crankcase Capacity
4 Cylinder 4 qt.
6 Cylinder 4 qt.
8 Cylinder (283) 4 qt.
8 Cylinder (327) 4 qt.
8 Cylinder (350) 4 qt.
8 Cylinder (396) 4 qt.
8 Cylinder (427) Chevrolet 4 qt.
8 Cylinder (427) Corvette 5 qt.
For 4 Cyl. Add .5 qt. with filter change;
1 qt. for 6 and 8 Cyl. engines.
Lubrication
Crankcase oil should be selected to give the best per-
formance under the climatic and driving conditions in the
territory in which the vehicle is driven.
During warm or hot weather, an oil which will provide
adequate lubrication under high operating temperatures
is required.
During the colder months of the year* an oil which will
permit easy starting at the lowest atmospheric tempera-
ture likely to be encountered, should be used.
When the crankcase is drained and refilled, the crank-
case oil should be selected, not on the basis of the exist-
ing temperature at the time of the change, but on the
lowest temperature anticipated for the period during
which the oil is to be used.
Unless the crankcase oil is selected on the basis of
viscosity or fluidity of the anticipated temperature, dif-
ficulty in starting will be experienced at each sudden
drop in temperature.
SAE Viscosity Oils
SAE Viscosity Numbers indicate only the viscosity or
body of the oil, that is, whether an oil is a light or a
heavy body oil, and do not consider or include other
properties or quality factors.
The lower SAE Viscosity Numbers, such as SAE 5W
and SAE 10W which represent the light body oils, are
recommended for use during cold weather to provide
easy starting and instant lubrication. The higher SAE
Viscosity Numbers such as SAE 20 and SAE 20W, which
represents heavier body oils, are recommended for use
during warm or hot weather to provide improved oil
economy and adequate lubrication under high operating
temperatures.
Oils are available which are designed to combine the
easy starting characteristics of the lower SAE Viscosity
Number with the warm weather operating characteristics
of the higher SAE Viscosity Number. These are termed
"multi-viscosity oils," SAE 5-10W, SAE 5W-20, SAE
10W-20W, and SAE 10W-30.
The following chart will serve as a guide for the
selection of the correct SAE Viscosity Number for use
under different atmospheric temperature ranges, and
suggests the appropriate SAE Viscosity Numbers when
multi-viscosity oils are used.
Lowest Anticipated
Temperature
During Time
Oil Will Be
in Crankcase
32°F.
0°F.
Below 0°F.
Recommended
SAE Viscosity
Oils
SAE 20 or 20W
SAE 10W
SAE 5W
Recommended
SAE
Multi-
Viscosity
Oils
SAE 10W-30 .
SAE 10W-30
SAE 5W-20
SAE 30 or 10W-30 is recommended when most of the
driving is at high speeds and/or at temperatures above
90
°F.
CHEVROLET CHASSIS SERVICE MANUAL

LUBRICATION 0-14
SAE 5W-30 oils may be used during periods when
temperatures of 32° and below are to be expected.
Types of Oils
In service, crankcase oils may form sludge and varnish
and under some conditions, corrosive acids unless pro-
tected against oxidation.
To minimize the formation of these harmful products
and to assure the use of oil best suited for present day
operating conditions, automobile manufacturers have de-
veloped a series of sequence tests designed to evaluate
the ability of any oil to properly lubricate automobile
engines.
It is recommended that only those oils which are
certified by their suppliers as meeting or exceeding the
maximum severity requirements of these sequence tests
(or GM Standard 4745-M) be used in Chevrolet engines.
Certified sequence tested oils will be described as such
on their containers.
Maintaining Oil Level
The oil gauge rod is marked "Full" and "Add Oil."
These notations have broad arrows pointing to the level
lines.
The oil level should be maintained between the
two lines, neither going above the "Full" line nor under
the "Add Oil" line. DO NOT OVERFILL. After operating
vehicle allow a few minutes for oil to return to crankcase
before checking oil level.
Check the oil level frequently and add oil when
necessary.
Oil and Filter Change Intervals
NOTE:
Under prolonged dusty driving condi-
tions,
it is recommended that these operations
be performed more often.
OIL
To insure continuation of best performance, low main-
tenance cost and long engine life, it is necessary to
change the crankcase oil whenever it becomes contami-
nated with harmful foreign materials. Under normal
driving conditions draining the crankcase and refilling
with fresh oil every 60 days or every 6000 miles which-
ever occurs first, is recommended.
It is always advisable to drain the crankcase only after
the engine has become thoroughly warmed up or reached
normal operating temperature. The benefit of draining is,
to a large extent, lost if the crankcase is drained when
the engine is cold, as some of the suspended foreign
material will cling to the sides of the oil pan and will not
drain out readily with the cold, slower moving oil.
OIL FILTER
Change engine oil filter every 6000 miles or every 6
months, whichever occurs first.
NOTE:
For Vehicles in heavy duty operation
involving continuous start-stop or prolonged idl-
ing, engine oil should be changed after 2500-
3000 miles of operation. The filter should be
changed after 5000-6000 miles of operation.
Crankcase Dilution
Probably the most serious phase of engine oil deterio-
ration is that of crankcase dilution which is the thinning
of the oil by fuel vapor leaking by pistons and rings and
mixing with the oil and by condensation of water on the
cylinder walls and crankcase.
Leakage of fuel, or fuel vapors, into the oil pan occurs
mostly during the "warming up" period when the fuel is
not thoroughly vaporized and burned. Water vapor enters
the crankcase through normal engine ventilation and
through exhaust gas blow-by. When the engine is not
completely warmed up, these vapors condense, combine
with the condensed fuel and exhaust gases and form acid
compounds in the crankcase.
As long as the gases and internal walls of the crank-
case are hot enough to keep water vapor from con-
densing, no harm will result. However, when the engine
is run in low temperatures moisture will collect and
unite with the gases formed by combustion resulting in
an acid formation. The acid thus formed is likely to
cause serious etching or pitting which will manifest itself
in excessively rapid wear on piston pins, camshaft
bearings and other moving parts of the engine, oftentimes
causing the owner to blame the car manufacturer or the
lubricating oil when in reality the trouble may be traced
back to the character of fuel used, or a condition of the
engine such as excessive blowby or improper carburetor
adjustment.
Automatic Control Devices to Minimize
Crankcase Dilution
All engines are equipped with automatic devices which
aid greatly in minimizing the danger of crankcase
dUution.
The thermostat, mounted in the cylinder head water
outlet, restricts the flow of water to the radiator until a
predetermined temperature is reached, thus minimizing
the length of time required to reach efficient operating
temperature, reducing the time that engine temperatures
are conducive to vapor condensation.
A water by-pass is included in the cooling system,
utilizing a hole in the front of, the cylinder block. This
allows a limited circulation of coolant, bypassing the
thermostat until thermostat opening temperatures are
reached. This system provides a uniform coolant tem-
perature throughout the engine, eliminating localized
hot-spots, improving exhaust valve life, provides fast
warmrup of lubricating oil and fast temperature rise in
the coolant which provides fast heater operation in cold
weather.
A thermostatic heat control on the exhaust manifold
during the warming up period, automatically directs the
hot exhaust gases against the center of the intake mani-
fold, greatly aids in proper vaporization of the fuel.
An automatic choke reduces the danger of raw or
unvaporized fuel entering the combustion chamber and
leaking into the oil reservoir.
An.
efficient crankcase ventilating system drives off
fuel vapors and aids in the evaporation of the raw fuel
and water which may find its way into the oil pan.
CRANKCASE BREATHER CAP
Clean and re-oil at every oil change..
CHEVROLET CHASSIS SERVICE MANUAL

LUBRICATION 0-15
CRANKCASE VENTILATION VALVE
VALVE TYPE
NOTE: Under prolonged dusty driving condi-
tions,
it is recommended that these operations
be performed more often. Every 12,000 miles
or 12 months the valve should be replaced.
Connecting hoses, fittings, flame arrestor and
crankcase breather cap (where used) should be
cleaned. At every oil change the system should
be tested for proper function and serviced, if
necessary.
FUEL FILTER
Replace filter element located in carburetor inlet if
flooding occurs, if engine surges during constant speed
operation (pulsating effect) or if poor performance is
experienced during acceleration or at higher speeds.
AIR CLEANER
NOTE: Under prolonged dusty driving condi-
tions,
it is recommended that these operations
be performed more often.
POLYURETHANE TYPE-
Every 12,000 miles clean element in solvent, squeeze
out solvent, then soak in engine oil and squeeze out
excess.
OIL WETTED PAPER ELEMENT TYPE-
First 12,000 miles inspect or test element; if satis-
factory, re-use element but recheck every 6,000 miles
until replaced. Element must not be washed, oiled,
tapped or cleaned with an air hose.
BATTERY TERMINAL WASHERS
Battery terminals have felt washers between top of
case and cable connections to minimize corrosive action
of battery acid. These felt washers should be saturated
with engine oil every 6,000 miles.
DISTRIBUTOR
4 and 6-Cylinder Engine—Remove distributor cap and
rotate lubricator 1/2 turn at 12,000 mile intervals. Re-
place at 24,000 mile intervals.
8-Cylinder Engine—Change cam lubricator end for end
at 12,000 mile intervals. Replace at 24,000 mile
intervals.
REAR AXLE AND 3-SPEED AND
OVERDRIVE, 4-SPEED TRANSMISSIONS
The passenger car operates under the most severe
lubrication conditions at high speed and requires a hypoid
lubricant which will meet this condition.
Recommended Lubricants
Standard Rear Axles—SAE 90 "Multi-Purpose" gear
lubricant.
Positraction Rear Axles—Use special Positraction
lubricant.
CAUTION: Straight Mineral Oil gear lubricants
must not be used in hypoid rear axles.
Transmissions—SAE 90 "Multi-Purpose" gear
lubricant.
The SAE 90 viscosity grade is recommended for year
round use. However, when extremely low temperatures
are encountered for protracted periods during the winter
months, the SAE 80 viscosity grade may be used.
"Multi-Purpose" Gear Lubricants
Gear lubricants that will satisfactorily lubricate hypoid
rear axles have been developed and are commonly re-
ferred to as ' 'Multi-Purpose" gear lubricants meeting
U.S.
Army Ord. Spec. MIL-L-2105B.
These lubricants can also be satisfactorily used in
manual transmissions.
CAUTION: With Positraction rear axles use
special Positraction lubricant.
"Multi-Purpose" gear lubricants must be manufac-
tured under carefully controlled conditions and the
lubricant manufacturer must be responsible for the
satisfactory performance of his product. His reputation
is the best indication of quality.
Lubricant Additions
The lubricant level in the axle and transmission hous-
ings should be checked periodically. (Every 6,000 miles.)
It is recommended that any additions required to bring
up the lubricant level be made using the same type lubri-
cant already in the housing.
When checking lubricant level in transmission or rear
axle the unit being cheeked should be at operating
temperature. With unit at operating temperature the
lubricant should be level with bottom of the filler plug
hole.
If the lubricant level is checked with the unit cold
the lubricant level should be 1/2 inch below the filler
plug hole.
Lubricant Changes
The rear axle lubricant does not require changing for
the life of the vehicle. If additions are needed, or when
refilling the axle after service procedures, use lubricants
described above.
POWERGLIDE TRANSMISSION
NOTE: Every 12,000 miles, it is recommended
that the Powerglide low band be adjusted as
specified in Section 7 of this manual.
Every 6,000 miles--Check fluid level on dipstick with
engine idling, selector lever in neutral position, parking
brake set and transmission at operating temperature. If
fluid level is below full mark on dip stick, adding a small
amount of Automatic Transmission Fluid, General Motors
Automatic Transmission Fluid (Part Numbers 1050568-
69,
70) is recommended. If this fluid is not obtainable,
use Automatic Transmission Fluid Type 'A' bearing the
mark AQ-ATF followed by a number and the suffix letter
'A'.
Recheck fluid level on dip stick and again add a
small amount of fluid if needed to bring level to full
mark. DO NOT OVERFILL.
CHEVROLET CHASSIS SERVICE MANUAL

HEATER AND AIR CONDITIONING 1A-30
Leak Detector
Tool J-6084 (fig. 43) is a propane gas-burning torch
which is used to locate a leak in any part of the system.
Refrigerant gas drawn into the sampling tube attached to
the torch will cause the torch flame to change color in
proportion to the size of the leak. Propane gas fuel
cylinders used with the torch are readily available
commercially throughout the country.
CAUTION: Do not use lighted detector in any
place where combustible or explosive gases,
dusts or vapors may be present;
Operating Detector
1.
Open control valve only until a low hiss of gas is
heard, then light gas at opening in chimney.
2.
Adjust flame until desired volume is obtained. This
is most satisfactory when blue flame is approxi-
mately 3/8" above reactor plate. The reaction plate
will quickly heat to a cherry red.
3.
Explore for leaks by moving the end of the sampling
hose around possible leak points in the system. Do
not pinch or kink hose.
NOTE: Since R-12 is heavier than air, it is
good practice to place open end of sampling tube
immediately below point being tested, partic-
ularly in cases of small leaks.
CAUTION: Do not breathe the fumes that are
produced by the burning of R-12 gas in the de-
tector flame, since such fumes can be toxic in
large concentrations of R?»12.
4.
Watch for color changes. The color of the flame
which passes through the reaction plate will change
to yellow when sampling hose draws in very small
CHIMNEY
REACTION PLATE
BURNER HEAD
Fig.
43—Leak Detector
leaks of R-12. Large leaks will be indicated by a
change in color to a vivid purplish-blue. When the
sampling hose passes the leak, the flame will clear
to an almost colorless pale-blue again. If the flame
remains yellow when unit is removed from leak,
insufficient air is being drawn in or the reaction
plate is dirty.
NOTE: A refrigerant leak in the high pressure
side of the system may be more easily detected
when, if possible, the system is in operation. A
leak on the low pressure side may be most
easily detected after the engine has been shut
off for several minutes to allow system pres-
sures to equalize. This particularly applies to
the front seal.
VACUUM PUMP
A vacuum pump should be used for evacuating air and
moisture from the air conditioning system.
Vacuum pump, Tool J-5428, (fig.. 44) is available for
this purpose. It is used as a component part of the
Charging Station J-8393, described previously. The fol-
lowing precautions should be observed relative to tbe
operation and maintenance of this pump.
' • Make sure dust cap on discharge outlet of vacuum
pump is removed before operating.
• Keep all openings capped when not in use to avoid
moisture being drawn into the system.
• Oil should be changed after every 250 hours of nor-
mal operation.
To change oil, simply unscrew hex nut located on
back side of pump, tilt backward and drain out oil
(fig. 44). Recharge with 8 ounces of vacuum pump
oil.
If you desire to flush out the pump, use this
same type clean oil. Do not use solvent.
NOTE: Improper lubrication will shorten the
life of pump.
• If this pump is subjected to extreme or prolonged
cold, allow it to remain indoors until oil has reached
approximate room temperature. Failure to warm oil
will result in a blown fuse.
• A five ampere time delay cartridge fuse has been
installed in the common line to protect the windings
of the compressor. The fuse will blow if an ex-
cessive load is placed on the pump. In the event the
fuse is blown, replace with a five ampere time delay
fuse - do not use a substitute fuse as it will result in
damage to the starting windings.
• If the pump is being utilized to evacuate a burnt-out
system, a filter must be connected to the intake
fitting to prevent any sludge from contaminating the
working parts, which will result in malfunction of the
pump.
• Do not use the vacuum pump as an air compressor.
AVAILABILITY OF REFRIGERANT-12
Refrigerant-12 is available through Parts Stock in 25
lb.
drums and in 15 oz. disposable cans. Valves are
available for
the"
disposable cans, which may be used as
individual cans or as a group of up to four cans (fig. 45).
Tool J-6272 is used with one through four cans. The
use of the four-can fixture makes it possible to charge
the system with a known quantity of refrigerant without
CHEVROLET CHASSIS SERVICE MANUAL

HEATER AND AIR CONDITIONING 1A-37
VACUUM SYSTEM COMPONENT FUNCTION
Component
Air Door Diaphragm
Power Servo
Vacuum Relay Valve
Mode Door Diaphragm
Defroster Diaphragm
Transducer
Thermo Vacuum Valve
Vacuum Applied
Air Door Open to Outside Air
(Closed to Car Body)
Maximum Heat
Vacuum Applied to One Port Opens a Passage
Through the Valve to Allow Transducer Vacuum
to be Supplied to the Power Servo
Vacuum to Linkage Side
Air Flow Out Heater
Ducts
Full Airflow Out Heater
Outlet
Vacuum to Covered Side
Airflow Out of Upper
Outlets
Full Airflow Out Defroster
Outlets (Full De-ice)
No Vacuum Applied
Air Door Open to
Re circulated Air
(Open to Car Body)
Maximum Cooling
No Vacuum Applied Closes
Vacuum Supply to Power
Servo
Airflow Out of Upper and
Lower Outlets Door Open
1"
from 100% Lower Out-
let Position
Airflow Divided 1/3 Out
Defroster Outlets 2/3
Out Heater Outlets
Supplies Modulated Vacuum to Power Servo
Zero Voltage Applied to Transducer
Results in Maximum Vacuum Supply
10 Volts Applied to Transducer
Results in No Vacuum Supply
(Coolant Hot) Passes Vacuum When System is Calling For Outside Air
MAINTENANCE AND ADJUSTMENTS
EVAPORATOR CONTROL VALVE (POA)
(Chevrolet, Chevelle, Comoro, and Corvette
Four Season) (Chevrolet Comfortron)
The only check for proper POA valve operation is to
check the suction pressure at the valve as during a
performance test. The POA valve is an absolute valve
and will provide different gauge readings based on the
altitude where the readings are being taken. Correct
gauge reading at sea level is 29.5 psig. Gauge readings
will be one-half psi higher for each additional 1000 feet
of elevation. The following table lists gauge readings at
different altitudes. If a valve gives improper gauge
readings, it must be replaced since it is not repairable
or adjustable.
29.5
30.0
30.5
31.0
31.5
32.0
32.5
33.0
33.5
34.0
34.5
psig.
psig.
psig.
psig.
psig.
psig.
psig.
psig.
psig.
psig.
psig.
— Sea 1
— 1000
— 2000
— 3000
— 4000
— 5000
— 6000
— 7000
— 8000
— 9000
Level
ft.
ft.
ft.
ft.
ft.
ft.
ft.
ft.
ft.
— 10000 ft.
THERMOSTATIC SWITCH
(Universal and Chevy II All-Weather System)
Thermostatic switches used in Universal and All-
Weather systems differ only in the capillary tube sensing
unit.
The Chevy n All-Weather System thermostatic switch
has an air sensing capillary which is coiled and attached
to the front of the evaporator core with plastic plugs.
This type of unit is controlled by the temperature of the
air leaving the evaporator.
Universal systems make use of a thermostatic switch
with a fin sensing capillary or a self-supporting air sens-
ing capillary. This capillary controls the switch by
sensing the temperature of the metal fins or the air
leaving the fins.
Checking for Proper Operation
1.
Install the gauge set and set up the vehicle as
described under Performance Test.
2.
Movement of the temperature control knob should
result in a definite change in suction pressure and
cycling of the compressor clutch.
• If compressor continues to operate regardless of
the knob adjustment, it indicates that the points
CHEVROLET CHASSIS SERVICE MANUAL

CORVETTE BODY 1B-T9
Fig.
43—Removing Regulator Assembly
REAR QUARTER
DOOR SILL PLATE AND MOLDING
Figure 49 shows assembly details of both the door sill
plate and molding. The sill plate which retains the car-*
pet, the cowl trim windlace and lock pillar front edge
trim are retained to the body by six screws.
The molding assembly, which replaces a rocker panel,
is quickly and easily replaced by removing 10 retaining
screws. The sill molding retainer is also fastened to the
body with screws.
REAR END
FOLDING TOP COMPARTMENT LID
Adjustments
Hinges
The folding top compartment lid should be adjusted so
that in the closed position the surface of the lid is flush
with surrounding body surfaces and space between lid
edge and body is 1/16" to 3/16" at sides and 3/16" to
1/4" at rear. Whenever lid position is changed on hinges,
lock engagement must be inspected and adjusted if neces-
sary. Adjust hinge position as follows:
1.
Scribe a line on lid surface following contour of hinge
strap.
This will ease observation of lid movement
during adjustment (fig. 51).
2.
To raise or lower top surface of lid, add or remove
hinge shims.
3.
To adjust spacing between lid edges and body, loosen
hinge-to-lid screws and shift lid as required.
Lock
Lock engagement may be adjusted as follows:
1.
Striker plates may be shimmed to adjust the depth
of lock engagement in striker plate. When this ad-
justment is made, release of lock should be tested
and adjusted as required.
2.
Release of lock may be adjusted by loosening lock
assembly retaining bolts and moving lock in ap-
propriate direction to the limit of slotted holes in
, lock base. Further adjustment may be gained by
moving cable retainer in appropriate direction.
Hinges
(Refer to Figure 52)
Removal
1.
Scribe around hinge as shown in Figure 51.
2.
Hinge may be removed as an assembly by opening
top compartment lid fully and removing 3 retaining
screws. Note number of shims found between hinge
frame and compartment floor.
3.
To remove spring from hinge assembly, close top
compartment lid as far as possible and insert Tool
J-9559 between expanded coils in spring. Opening
top compartment lid fully will allow removal of
spring as shown in Figure 53.
4.
As soon as spring is removed, insert long bolt sup-
plied with J-9559 through holes in end of tool, pass-
ing it through spring, and install nut on bolt.
Spring may be removed from J-9559 or J-9559 may be
installed in a new spring, by the following method:
1.
Place a closed 6 or 8 inch "C" clamp in a vise or
fasten it to a heavy bench top (bench should be fas-
tened to floor).
2.
Hook one end of spring in clamp and the other end
in hook of chain hoist, "cherrypicker" or equivalent,
as shown in Figure 54.
3.
Stretch the spring enough to allow insertion of
J-9559. Install through bolt if spring is not to be in-
stalled on hinge at once.
installation
1.
Install same number of shims as removed or, if
repairing collision damage, etc., position hinge in
compartment, install upper mounting screws, fill
gap between floor and hinge frame with shims and
install lower mounting screw.
2.
If spring has been removed from hinge, install
spring in J-9559 and place spring on hinge with com-
partment lid raised; closing lid releases J-9559 for
removal. Upper end of spring should rest in one of
three notches yielding best lid operation. About 3
pounds pressure should be necessary to close lid.
Lock
Removal
1.
Remove cable mounting clamps. Remove retainer
from control cable assembly and disengage cable
from control.
2.
Scribe a mark on lid following outer contour of lock
assembly.
3.
Remove 3 lock assembly retaining screws and re-
move lock from compartment lid.
Installation
1.
Place lock assembly on compartment lid within
scribed line and install retaining screws.
2.
Install end of cable in control assembly and fasten
retainer securely.
3.
Test operation of lock thoroughly, adjusting if neces-
sary as outlined in this section.
Control
Removal
1.
Remove inner mounting clamps from both cables
and disengage cables from control by removing
retainers.
CHEVROLET CHASSIS SERVICE MANUAL

FRONT SUSPENSION 3-6
Fig.
8 - Caster and Camber Adjustments - Chevy
To adjust for caster and camber, loosen the upper sup-
port shaft to crossmember nuts, add or subtract shims as
required and retighten nuts.
NOTE:
Caster and camber can be adjusted in
one operation.
Caster and camber specifications will be found in the
last section of this book.
Chevrolet and Chevy II
The caster angle is adjusted by turning the two niits at
the front of the lower control arm strut rod (figs. 7 and
8).
Shortening this rod will increase caster. Lengthen-
ing will decrease caster.
Camber angle is adjusted by loosening the lower con-
trol arm pivot bolt and rotating the cam located on this
pivot. This eccentric cam action will move lower control
arm in or out, thereby varying camber.
Steering Axis Inclination Adjustment
"Camber" is the outward tilt of the wheel and "steering
axis inclination" is the inward tilt of the knuckle. Cam-
ber cannot be changed without changing steering axis
inclination. Correct specifications willbe found at the
end of this section. If, with the camber correctly ad-
justed, the steering axis inclination does not fall within
the specified limits the knuckle is bent and should be
replaced.
If a new knuckle is installed, caster, camber and toe-in
must be readjusted.
Toe-In Adjustment
Toe-in, the inward pointing of both front wheels, is
checked with the wheels in the straight ahead position. It
is the difference of the distance measured between the
extreme front and the distance measured between the ex-
treme rear of both front wheels. Correct toe-in specifi-
cations will be found at the end of this section.
NOTE:
Toe-in must be adjusted after caster
and camber adjustment.
A. If the equipment being used measures the toe-in of
each wheel individually:
1.
Set the steering gear on the high point, mark 12
o'clock position on the steering shaft and position
the steering wheel for straight ahead driving.
2.
Loosen the clamp bolt at each end of each tie rod
and adjust to the total toe-in as given in the speci-
fications at the end of this book.
B.
If a tram gauge is being used, proceed as follows:
1.
Set the front wheels in the straight ahead position.
2.
Loosen the clamp bolts on one tie rod and adjust
for the proper toe-in as given in the specifications
at the end of this book.
3.
Loosen the clamp bolts on the other tie rod. Turn
both rods the same amount and in the same direc-
tion to place the steering gear on its high point and
position the steering wheel in its straight ahead
position.
C.
After the adjustment has been made:
1.
a. Chevrolet—Position inner tie rod clamp bosses
forward to 90° down to avoid stabilizer link bolt
interference.
b.
Chevelle—Position the tie rod clamp bosses
down to 45?° forward to avoid interference.
c. Chevy II--Position the outer tie rod clamp
bosses forward and not more than 45° up or
down from horizontal to avoid interference.
Inner clamps forward and vertical.
d. Corvette--Position inner tie rod clamps with
bolt horizontal and down. Position outer clamps
with bolt vertical and to the rear.
e. Camaro—Position inner tie rod clamps with
open end of clamp and slot in line. Position
relative to ground unimportant. Position outer
clamps with bolt top and 30° either side of ver-
tical. Position relative to slot unimportant.
RIDING HEIGHT AND COIL SPRING SAG
The following check will quickly determine whether or
CHEVROLET CHASSIS SERVICE MANUAL

REAR SUSPENSION AND DRIVE LINE 4-15
ship of parts, then install Spacer J-
7574-
3 over
the partially installed bushing and between the
sides of the control arm.
f. Continue to tighten J-
21058-
8
until bushing is
pulled flush against control arm. Do not exert
undue force against control arm after bushing is
installed. Overtightening of J-21058-
8
will cause
damage to walls of control arm.
g. Disassemble tools and inspect bushing for proper
installation.
Replace the rear bushing as follows:
a. Position Puller Screw J-21058-8 through Re-
mover Adapter J-21830-2 so that head of screw
is opposite button end of remover. Install this
assembly, threaded end of sc'rew first, through
bushing to be removed.
b.
Install Receiver J-21830-4 and Bridge J-21830-7
. over screw and against control arm. Position
thrust bearing against J-21830-7 and screw
J-21058-8 snugly against bearing. Install Spacer
J-
2183d-
3
between sides of control arm and over
bushing.
c. Check tool installation for proper alignment and
tighten J-21058-8 to withdraw bushing from con-
trol arm. Refer to Figure 35 for installed view
of tools.
d. Disassemble tools and position Installer Adapter
J-21830-2 on flanged end of new bushing. Posi-
tion bushing in control arm making sure of cor-
rect installation. Small end of bushing will pass
through one side of arm without any interference.
e. Install J-21830-4, J-21830-7, thrust bearing and
J-21058-8 on threaded end of J-21058-15 as
shown in Figure 36. Tighten J-21058 to main-
tain proper relationship of parts; then position
Spacer J- 21830- 3 over bushing and between sides
of control arm.
f. Tighten J-21058-8 until bushing is fully seated
J-21058-8 J-21830-7 J-21830-4 J-21830-3 J-21830-2
\
J-2K
X
D58-8
J-218
30-7
IP
•he?
21830-4
J-21830-2
JfSir
J-21830-3
Fig.
35—Lower Control Arm Rear Bushing Removal
(Chevrolet)
Fig.
36—Lower Control Arm Rear Bushing Installation
(Chevrolet)
against side of control arm. Do not apply undue
pressure to J-21058 after bushing is seated--to
do so may cause permanent distortion to control
arm.
g. Disassemble tools and check bushing for proper
installation.
Installation
NOTE:
Make sure control arm is reinstalled
in proper forward attaching position. Reinstall
in same hole as noted during removal. Top
attaching hole is used for all installations except
station wagons and heavy-duty suspension (RPO
F41).
Opposite arm must be installed in cor-
responding position.
1.
Position the control arm between the mounting
brackets and loosely install the pivot bolt retaining
nuts in the proper position.
2.
Install spring and shock absorber as outlined in this
section.
3.
Lower vehicle so that weight is placed on sus-
pension components and torque all affected parts to
specifications.
Chevelle Upper and Lower
Removal
NOTE:
If both upper control arms and both
lower control arms are to be removed at the
same time, remove both coil springs as outlined
under "Coil Spring Removal".
1.
Raise vehicle to a height that will allow axle assem-
bly to hand freely and position supports under both
frame side rails.
2.
Support axle assembly with an adjustable lifting de-
vice and raise rear axle assembly until tension is
relieved in control arm being removed.
3.
Disconnect control arm at forward and rearward
attaching points and remove from vehicle.
Bushing Replacement
The upper arm front bushing and carrier ear bushings
are of the same part number and are interchangeable.
CHEVROLET CHASSIS SERVICE MANUAL