automatic transmission fluid CHEVROLET CAMARO 1967 1.G Chassis Workshop Manual

Page 15 of 659


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

Page 17 of 659


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

Page 18 of 659


LUBRICATION 0-16

Every 12,000 miles (more frequently*, depending on

severity of service, if vehicle is used to pull trailers,

carry full loads during high ambient temperatures,

operate in mountainous terrain or operate under other

severe conditions--Remove fluid from the transmission

sump and add one and a half quarts of fresh fluid for

Camaro and Chevy II and two quarts for Chevrolet,

Chevelle, and Corvette. Operate transmission through all

ranges and check fluid level as described above.

•Except if vehicle is equipped with transmission pro-

vided in heavy duty service options. If so equipped,

drain converter and pump every 12,000 miles and add

approximately seven and a half quarts of fresh fluid

for Chevy II and nine quarts for Chevrolet and Chevelle.

TURBO HYDRA-MATIC

Lubrication. recommendations for the Turbo Hydra-

Matic are the same as outlined for the Powerglide

transmission except for fluid capacity and filter change

listed below.

After checking transmission fluid level it is important

that the dip stick be pushed all the way into the fill tube.

Every 12,000 miles — after removing fluid from the

transmission sump, approximately 7 1/2 pints of fresh

fluid will be required to return level to proper mark on

the dip stick.

Every 24,000 miles, or at every other fluid change--

the transmission sump strainer should be replaced.

FRONT WHEEL BEARINGS

It is necessary to remove the wheel and hub assembly

to lubricate the bearings. The bearing assemblies should

be cleaned before repacking with lubricant. Do not pack

the hub between the inner and outer bearing assemblies

or the hub caps, as this excessive lubrication results in

the lubricant working out into the brake drums and

linings.

Front wheels of all passenger car models are equipped

with tapered roller bearings and should be packed with a

high melting point water resistant front wheel bearing

lubricant whenever wheel and hub are removed.

CAUTION: "Long fibre" or "viscous" type

lubricant should not be used. Do not mix wheel

bearing lubricants. Be sure to thoroughly clean

bearings and hubs of all old lubricant before

repacking.

The proper adjustment of front wheel bearings is one

of the important service operations- that has a definite

bearing on safety. A car with improperly adjusted front

wheel bearings lacks steering stability, has a tendency to

wander or shimmy and may have increased tire wear.
The adjustment of these bearings is very critical. The

procedure is covered in Section 3 of this manual under

Front Wheel Bearings—Adjust,

MANUAL STEERING GEAR

Check lubricant level every 36,000 miles. If required,

add EP Chassis Lubricant.

POWER STEERING

On models equipped with power steering gear, check

fluid at operating temperature in pump reservoir. Add

GM Power Steering Fluid, or, if this is not available, use

Automatic Transmission Fluid "Type A" bearing the

mark AQ-ATF followed by a number and the suffix letter

'A'
to bring level to full mark on dip stick.

AIR CONDITIONING

After the first 6,000 miles, check all hose clamp

connections for proper tightness.

Every 6,000 miles check sight glass under the hood,

after the system has been in operation for several

minutes. Sight glass should be clear but may, during

milder weather, show traces of bubbles. Foam or dirt

indicate a leak which should be repaired immediately.

BRAKE MASTER CYLINDER

Check level every 6,000 miles and maintain 1/4" below

lowest edge of each filler opening with GM Hydraulic

Brake Fluid Supreme No. 11.

PARKING BRAKE

Every 6,000 miles, apply water resistant lube to park-

ing brake cable, cable guides and at all operating links

and levers.

CLUTCH CROSS-SHAFT

Periodic lubrication of the clutch cross shaft is not

required. At 36,000 miles or sooner, if necessary;

remove plug, install lube fitting and apply CHASSIS

LUBRICANT.

CHASSIS LUBRICATION

For chassis lubrication, consult the lubrication chart.

It shows the points to be lubricated and how often the

lubricant should be applied.

The term "chassis lubricant" as used in this manual,

describes a water resistant EP chassis grease designed

for application by commercial pressure gun equipment.

CHEVROLET CHASSIS SERVICE MANUAL

Page 19 of 659


LUBRICATION 0-17

LUBRICATE EVERY 6,000 MILES

LUBRICATE EVERY 12,000 MILES

LUBRICATE EVERY 36,000 MILES

Refill Positraction Rear Axle with

Special Lubricant Only.
GL—Multi-purpose
or
Universal Gear Lubricant4

WB-Wheel Bearing Lubricant

(Whenever Brakes are serviced)

CL—Chassis Lubricant

EO-EngineOil
AT-Automatic Transmission Fluid {Type
A)

BF-Brake Fluid

Fig.
32—Lubrication Diagram—Chevrolet

1.
Front Suspension

2.
Steering Linkage

3. Steering Gear
4.
Air Cleaner

5. Crankcase Breather Cap

6. Front Wheel Bearings
7. Transmission

8. Rear Axle

9. Oil Filter
10.
Battery

11.
Parking Brake

12.
Brake Master Cylinder

CHEVROLET CHASSIS SERVICE MANUAL

Page 20 of 659


LUBRICATION 0-18

12

LUBRICATE EVERY 6000 MILES GL -Multi-purpose Gear Lubricant*

WB—Wheel Bearing Lubricant

LUBRICATE EVERY 12000 MILES (Whenever Brakes are serviced)

CL —Chassis Lubricant

LUBRICATE EVERY 36000 MILES E°-En9ine°il

"Refill Positraction Rear Axle with Special Positraction Rear Axle

Lubricant Only.
AT —Automatic Transmission Fluid (Type A)

SL —Steering Gear Lubricant

BF -Hydraulic Brake Fluid

1.
Front Suspension

2.
Steering Linkage

3. Steering Gear
Fig.
33—Lubrication Diagram—Chevelle

4.
Air Cleaner

5. Crankcase Breather Cap

6. Front Wheel Bearings
7. Transmission

8. Rear Axle

9. Oil Filter
10.
Battery

11.
Parking Brake

12.
Brake Master CylincU

CHEVROLET CHASSIS SERVICE MANUAL

Page 21 of 659


LUBRICATION
0-19

.
3-SPEED
4-SPEED

7 OVER DRIVE

10 9 5 1 6 2 '
AUTOMATIC

3 12 11

LUBRICATE EVERY 6,000 MILES GL-Gear Lubricant*

WB-Wheel Bearing Lubricant

(Wh Bk
AT-Automdtic Transmission Fluid

^ WB-Wheel Bearing Lubricant (Type A)

-TV
LUBRICATE
EVERY 12,000 MILES (Whenever Brakes are serviced)

' CL—Chassis Lubricant

• LUBRICATE EVERY 36,000 MILES EO_Engine Oil
BF
-Brake Fluid

•Refill Positt

Special Lubricant Only.
Axl«
with

1.
Front Suspension

2.
Steering Linkage

3. Steering Gear
Fig.
34—Lubrication Diagram—Chevy I!

4. Air Cleaner

5. Crankcase Breather. Cap

6. Front Wheel Bearings
7. Transmission

8. Rear Axle

9.
Oil Filter
10.
Battery

11.
Parking Brake

12.
Brake Master Cylinder

CHEVROLET CHASSIS SERVICE MANUAL

Page 22 of 659


LUBRICATION 0-20

3-SPEED

4—SPEED

AUTOMATIC

LUBRICATE EVERY 6000 MILES

LUBRICATE EVERY 12000 MILES

LUBRICATE EVERY 36000 MILES

*
Refill
positraction rear axle with

special lubricant only.
GL -GEAR LUBRICANT*

WB-WHEEL BEARING LUBRICANT

(WHENEVER BRAKES
ARE
SERVICED)

CL -CHASSIS LUBRICANT

CO-ENGINE
Oil;
AT -AUTOMATIC TRANSMISSION

FLUID (TYPE
A)

BF -BRAKE FLUID

Fig.
35—Lubricafion Diagram—Camaro

1.
Front Suspension

2.
Steering Linkage

3. Steering Gear
4.
Air Cleaner

5. Crankcase Breathe Cap

6. Front Wheel Bearings
7. Transmission

8. Rear Axle

9. Oil Filter
10.
Battery,

11.
Parking Brake

12.
Brake Master Cylinder

BODY LUBRICATION

See Body Service Manual
for
Body Lubrication,

cept Corvette)
(Ex-

CHEVROLET CHASSIS SERVICE MANUAL

Page 23 of 659


LUBRICATION
0-21

6

3-SPEED

4-SPEED

AUTOMATIC

10

LUBRICATE EVERY 6,000 MILES GL -Multi-purpose
or
Universal Gear Lubrincant*

-(V LUBRICATE EVERY 12,000 MILES WB-Wheel Bearing Lubricant

V/^ (Whenever Brakes
are
serviced)
AT —Automatic Transmission Fluid (Type)

BF -Brake Fluid

a
LUBRICATE EVERY 36,000 MILES

* Refill Positraction Rear Axle with

Special Lubricant Only.
CL -Chassis Lubricant

EO—Engine
Oil

Fig.
36—Lubrication Diagram—Corvette

1.
Front Suspension

2.
Steering Linkage

3. Steering Gear
4.
Air
Cleaner

5. Front Wheel

Bearings
6. Transmission

7. Rear Axle

8.
Oil
Filter
9. Battery

10.
Parking Brake

11.
Brake Master Cylinder

BODY LUBRICATION POINTS (CORVETTE)

Lubricate the following items when possible.

Hood Latch Mechanism and Hinges --Apply light engine oil

to pivot points. Don't oil lock pins or catch plates.

i

Rear Compartment Lid Release and Hinges --Apply light

engine
oil.

Side Door Hinge Pins—Apply light engine oil.
Door Lock Rotor and Striker Plate—Apply light engine oil or

stainless stick lubricant.

Lock Cylinders—Lubricate with powdered graphite.

Window Regulators and Controls and Door Lock Remote

Link —Apply light engine
oil.

Gas Tank Filler Cap Hinge—Apply light engine oil.

Weatherstrips and Rubber Bumpers —Coat lightly with
a

rubber lubricant.

CHEVROLET CHASSIS SERVICE MANUAL

Page 382 of 659


CLUTCH
AND
TRANSMISSIONS
7-23

Assembly (Fig.
4X)

1.
With detent spring tang projecting
up
over
the 3rd

and
4th
shifter shaft cover opening install
the
first

and second detent
cam
onto
the
detent
cam
pivot
pin.

With
the
detent spring tang projecting
up
over
the

first
and
second shifter shaft cover hole install
the

3rd
and 4th
detent
cam,

NOTE:
The 1-2
detent
cam has a
.090" greater

contour
on the
inside detent notch.

2.

3.
Install detent
cam
retaining
"C"
ring
to
pivot shaft,

and hook spring into detent
cam
notches.

Install
1-2 and 3-4
shifter shaft assemblies
in
cover

being careful
not to
damage seals. Install both shift

forks
to
shifter shaft assemblies, lifting
up on
detent
cam
to
allow forks
to
fully seat into position.

4.
Install reverse detent ball
and
spring
to
cover, then

install reverse shifter shaft assembly
to
cover.

5.
Install outer shifter levers, flat washers, lock wash-

ers
and
bolts.

Installation

1.
Shift shifter levers into neutral detent (center) posi-

tion. Position cover gasket
on
case.

2.
Carefully position side cover into place making sure

the shift forks
are
aligned with their respective

mainshaft clutch sliding sleeves.

Install cover attaching bolts
and
tighten evenly
to

specified torque.

Remove filler plug
and add
lubricant specified
in

Section
0, to
level
of
filler plug hole.
3.

4.

ALUMINUM POWERGLIDE

INDEX

Page

General
Description
7-23

Maintenance
and
Adjustments .............. 7—23

Oil
Level Check
7-23

Periodic
Oil
Change
7-24

Periodic
Low
Band Adjustment
7-24

Manual
Shift Linkage Check
and
Adjust
7-24

Floor
Shift Linkage
7-25

Floor
Mounted Control Lever
and

Bracket
Assembly
7-29

Throttle
Valve Linkage
.... 7-29

Neutral
Safety Switch
.. . 7-30

Throttle
Return Check Valve (Dashpot)
7-30

Component
Parts Replacement
7-30

Transmission
Replacement .............. 7—30
Page

Other
Service Operations
7-32

Diagnosis
7-32

Warming
Up
Transmission
7-32

Shop
Warm
Up , 7-32

Road
Warm
Up 7-32

Checking
Fluid Level
and
Condition
7-32

Manual
Linkage
7-32

Oil
Leaks
7-33

Basic
Pressure Checks
7-33

Wide
Open Throttle Upshift Pressure Check
.... 7-33

Idle
Pressure
in
Drive Range
7-33

Manual
"Low"
Range Pressure Check .......
7-33

Drive
Range Overrun (Coast) Pressure
.
.......
7-33

Powerglide
Shift Points
. . 7-35

GENERAL DESCRIPTION

The case
and
converter housing
of the two
speed alumi-

num Powerglide Transmission
is a
single case aluminum

unit. When
the
manual control
is
placed
in the
drive
po-

sition,
the
transmission automatically shifts
to low
gear

for initial vehicle movement.
As the car
gains speed
and

depending
on
load
and
throttle position,
an
automatic shift

is made
to
high gear.
A
forced downshift feature
pro-

vides
a
passing gear
by
returning
the
transmission
to low

range.

The
oil
pump assembly
is a
conventional gear type
and

the
oil
pump housing
is of the
large diameter type acting

as
the
front bulkhead
of the
transmission.
The
torque

converter
is a
conventional three element welded design

bolted
to the
engine flywheel which drives through
a
two-

speed planetary gearset.
The
high clutch assembly
is

typical
of the
designs used
in
this type transmission.
The

aluminum Powerglide uses
an
output shaft mounted
gov-
ernor which requires
a
hole through
the
output shaft.
The

reverse clutch assembly
is a
multiple disc type clutch.

The steel plates
are
splined directly
to the
case while
the

face plates
are
splined
to the
internal
or
ring gear.
The

clutch piston operates within
the
rear portion
of the
case.

The internal diameter
of the
pistoh
is
sealed to
an
integral

hub portion
of the
case rear bulkhead.
The
outside
dia-

meter
is
sealed
to a
machined portion
of the
case.
The

piston
is
hydraulically applied
and is
released
by
separate

coil springs.
The
valve body assembly
is
bolted
to the

bottom
of the
transmission case
and is
accessible
for

service
by
removing
the oil pan
assembly.
The
valve

body consists
of an
upper
and
lower body located
on
either

side
of a
transfer plate.
The
vacuum modulator
is lo-

cated
on the
left rear face
of the
transmission case.
The

modulator valve bore
is
located
in the
upper valve body.

MAINTENANCE
AND
ADJUSTMENTS

OIL LEVEL CHECK

The transmission
oil
level should
be
checked period-

ically
as
recommended
in
Section
0. Oil
should
be
added

only when level
is on or
below
the
"ADD" mark
on the dip

stick with
oil hot or at
operating temperature.
The oil

level
dip
stick
is
located
at the
right rear
of the
engine
compartment. Fill with
oil
specified
in
Section
0.

In order
to
check
oil
level accurately,
the
engine should

be idled with
the
transmission
oil hot and the
control

lever
in
neutral (N) position.

It
is
important that
the oil
level
be
maintained
no

higher than
the
"FULL" mark
on the
transmission
oil

level gauge.
DO NOT
OVERFILL,
for
when
the oil
level

CHEVROLET CHASSIS SERVICE MANUAL

Page 395 of 659


CLUTCH AND TRANSMISSIONS 7-36

TURBO HYDRA-MATIC TRANSMISSION

INDEX

Page

General Description . . , . 7-36

Maintenance and Adjustments . 7-37

Transmission Fluid 7-37

Fluid Level Indicator 7-37

Shift Control Linkage Adjustment ........... 7-37

Neutral Safety Switch Adjustment 7-37

Draining and Refilling Transmission . . . 7-37

Pressure Regulator Valve 7-38

Control Valve Body . 7-39

Governor ..'.... 7-40

Modulator and Modulator Valve 7-40

Parking Linkage . . 7-40
Page

Rear Seal -. 7-40

Other Service Operations . . 7-40

Transmission Replacement 7-40

Turbo Hydra-Matic Diagnosis Procedure. ......... 7-41

Sequence . ; ; 7-41

Oil Level and Condition Check 7-41

Manual Linkage 7-41

Oil Leaks .' 7-41

Case Porosity - Repair ................ 7-42

Oil Pressure Check 7-42

Transmission Shift Points 7-42

Special Tools 7-43

GENERAL DESCRIPTION

The Turbo Hydra-Matic transmission is a fully auto-

matic unit consisting primarily of a 3-element hydraulic

torque converter and a compound planetary gear set.

Three multiple-disc clutches, one sprag unit, one roller

clutch and two bands provide the friction elements re-

quired to obtain the desired function of the compound

planetary gear set.

The torque converter couples the engine to the plane-

tary gears through oil and provides hydraulic torque

multiplication when required. The compound planetary

gear set produces three forward speeds and reverse.

The
3-
element torque converter consists of a pump or

driving member, a turbine or driven member, and a

stator assembly. The stator is mounted on a one-way

roller clutch which will allow the stator to turn clock-

wise but not counter-clockwise.

The torque converter housing is filled with oil and

is attached to the engine crankshaft by a flex plate and

always rotates at engine speed. The converter pump is

an integral part of the converter housing, therefore the

pump blades, rotating at engine speed, set the oil within

the converter into motion and direct it to the turbine,

causing the turbine to rotate.

As the oil passes through the turbine it is traveling in

such a direction that if it were not re-directed by the

stator it would hit the rear of the converter pump blades

and impede its pumping action. So at low turbine speeds,

the oil is re-directed by the stator to the converter pump

in such a manner that it actually assists the converter

pump to deliver power or multiply engine torque.

As turbine speed increases, the direction of the oil

leaving the turbine changes and flows against the rear

side of the stator vanes in a clockwise direction. Since

the stator is now impeding the smooth flow of oil, its

roller clutch releases and it revolves freely on its shaft.

Once the stator becomes inactive, there is no further

multiplication of engine torque within the converter. At

this point, the converter is merely acting as a fluid

coupling as both the converter pump and turbine are

being driven at approximately the same speed - or at a

one-to-one ratio.

A hydraulic system pressurized by a gear type pump

provides the working pressure required to operate the

friction elements and automatic controls.

External control connections to transmission are:
Manual Linkage

Engine Vacuum

12 Volt Electrical

Signal
To select the desired op-

erating range.

To operate a vacuum mod-

ulator unit.

To operate an electrical

detent solenoid.

A vacuum modulator is used to automatically sense

any change in the torque input to the transmission. The

vacuum, modulator transmits this signal to the pressure

regulator for line pressure control, to the 1-2 accumula-

tor valve, and to the shift valves so that all torque re-

quirements of the transmission are met and smooth

shifts are obtained at all throttle openings.

The detent solenoid is activated by an alectric switch

on the carburetor. When the throttle is fully opened, the

switch on the carburetor is closed, activating the detent

solenoid and. causing the transmission to downshift at

speeds below approximately 70 MPH.

The selector quadrant has six selector positions: P,R,

N,D,
L2,L1.

P.
*
- Park position positively locks the output shaft to

the transmission case by means of a locking pawl

to prevent the vehicle from rolling in either di-

rection. The engine may be started in Park

position.

R. - Reverse enables the vehicle to be operated in a

reverse direction.

N.
- Neutral position enables the engine to be started

and run without driving the vehicle.

D,
- Drive Range is used for all normal driving condi-

tions and maximum economy. Drive Range has

three gear ratios, from the starting ratio to

direct drive. Detent downshifts are available by

depressing the accelerator to the floor.

L2.
- L2 Range has the same starting ratio as Drive

Range, but prevents the transmission from shift-

ing above second speed to retain second speed

acceleration when extra performance is desired.

L2 Range can also be used for engine braking.

L2 Range can be selected at any vehicle speed,

and the transmission will shift to second gear and

remain in second until the vehicle speed or the

throttle are changed to obtain first gear operation

in the same manner as in D Range.

CHIVROLET CHASSIS SERVICE MANUAL