1967 CHEVROLET CAMARO maintenance

CLUTCH AND TRANSMISSIONS 7-10 ,

GENERAL DESCRIPTION

The overdrive unit is essentially a two-speed planetary-

transmission attached to the rear of a conventional three-

speed transmission. In overdrive, engine speed is ap-

proximately 30 per cent slower at a given road speed

since the drive train includes planetary gears which pro-

vide a lower overall gear ratio than that obtained in high

gear with the conventional transmission.

The electrical equipment which controls the automatic

action of the mechanical portion of the overdrive unit

consists of a solenoid, a speed-sensitive governor switch,

a relay and a kickdown switch. The circuit including this

equipment makes it possible to operate in overdrive above

a pre-set cut-in speed, or in .conventional drive at any

speed.

With the overdrive unit engaged, the transmission

should not be left in any forward gear with intent of lock-

ing the drive-line as the overrunning clutch is a free-

wheeling condition.
SERVICING THE OVERDRIVE

With the,overdrive assembly removed from the trans-

mission, service operations on the transmission proper

are the same as for the standard three-speed trans-

mission.

Repairs to the overdrive housing, output shaft, ring

gear assembly, clutch cam, roller retainer, pinion cage,

sun gear, shift rail, sun gear control plate, output shaft

bearing, oil seal, speedometer drive gear, solenoid pawl

and interlock plunger may be performed underneath the

car, if so desired, by removing the overdrive housing

without disturbing the transmission. Refer to Overhaul

Manual for Service Procedure.

If the transmission mainshaft, overdrive adapter or

transmission rear bearing which is retained in adapter

require replacement, the entire transmission and over-

drive assembly should be removed and overhauled on the

bench.

MAINTENANCE AND ADJUSTMENTS

Servicing of the overdrive governor switch and pinion,

the sun gear solenoid, oil seal and cable bracket, the out-

put shaft rear oil seal, the control shaft lever, and the

speedometer driven gear may be accomplished without

removing the overdrive from the vehicle, as discussed

in the following paragraphs:

GOVERNOR SWITCH AND PINION

To remove governor switch, disconnect wires at gover-

nor switch and screw governor
out
of housing, using Tool

J-4653 on the flat hexagonal surface of governor case.

The pinion may be separated from the governor by re-

moving the snap ring on the shaft.

SUN GEAR SOLENOID, OIL SEAL AND

CONTROL CABLE BRACKET

Remove the solenoid by taking out the two mounting

bolts and lock washers, removing
the.
cable bracket with

the lower bolt. Turn the solenoid 1/4 turn and
pull,
sole-

noid plunger out of adapter. The oil seal may be pried

out of the adapter.

CASE REAR OIL SEAL

Removal

1.
Remove propeller shaft as outlined in Section 4.

2.
Using a punch against seal in housing, pry out seal

from housing.

Installation

1.
Prelubricate between sealing lips and coat outside of

new oil seal with a suitable sealant, then start seal

into bore in overdrive housing.

2.
Using Tool J-5154 drive oil seal into counterbore.

3.
Install propeller shaft as outlined in Section 4.

CONTROL SHAFT LEVER AND/OR "O" RING

OIL SEALS

To remove- the control shaft, disconnect the cpntrol
cable, remove tapered pin and pull lever out. Replace

the two "0" ring seals on the control shaft. Insert shaft

and new "O" ring seals into housing and install tapered

pin. Connect control wire to lever.

SPEEDOMETER DRIVEN GEAR

Disconnect speedometer cable, remove lock plate to

housing bolt and lock washer and remove lock plate. In-

sert screw driver in lock plate slot in fitting and pry

fitting, gear and shaft from housing. Pry "O" ring from

groove in guide.

Install new "O" ring in groove in fitting and insert

shaft.

Hold the assembly so slot in fitting is toward lock plate

boss on housing and install in housing. Push fitting into

housing until lock plate can be inserted in groove and

attached to housing.

L
dl

ZAIR GAP

km (CHECK WITH

M*= POINTS BARELY
'A

AoWER
|^

POINT

0 ADJUST

=^ i
SUPPORT

Fig. IB - Checking Relay Air Gap

CHEVROLET CHASSIS SERVICE MANUAL

CLUTCH AND TRANSMISSIONS 7-14

SPEED HEAVY DUTY TRANSMISSION

(WARNER MODEL T 16)

INDEX

General Description ......

Maintenance and Adjustments

Shift Linkage Adjustment

Side Cover ........

Removal .........

Disassembly
7-14

7-14

7-14

7-14

7-14

7-14
Assembly 7-14

Installation • 7-15

Other Maintenance
&
Adjustment

Operations See 3-Speed Saginaw Section

Transmission Replacement . . . See 3-Speed Saginaw Section

GENERAL DESCRIPTION

The Borg-Warner heavy duty three speed fully syn-

chronized (all forward gears) transmission incorporates

helical gears throughout specially designed to provide

high torque capacity, and gear teeth proportion to operate

at high speeds with neither excessive heat generation nor

excessive frictional losses. Shafts, bearings, high ca-

pacity clutches and other precision parts are held to

close limits providing proper clearances necessary for

durability during extended heavy usage.

The main drive gear is supported by a heavy duty ball

bearing at the front end of the transmission case and is

piloted at its front end in an oil impregnated bushing

mounted in the engine crankshaft. The front end of the

mainshaft is piloted in a row of roller bearings set into

the hollow end of the main drive gear and the rear end

is carried by a heavy duty ball bearing mounted in the

front of the extension housing.

The countergear is carried on a double row of rollers

at both ends while thrust is taken on thrust washers lo-

cated between the ends of the gear and the thrust bosses

in the case. An anti-rattle plate assembly at the front
of the countergear provides a constant spring tension be-

tween the counter and clutch gears to reduce torsional

vibrations. The reverse idler gear is carried on 25

roller bearings while thrust is taken on thrust washers

located between the ends of the gear and the thrust bosses

of the case.

Gear shifting is manual through shift control rods from

the shifter tube in the mast jacket to the rearward shift

lever of the side cover assembly for first and reverse

gear; and through a cross shaft assembly attached to the

forward side cover lever for second and third gear. All

three forward gears are fully synchronized. The syn-

chronizer assemblies consist of a clutch hub, clutch

sleeve, two clutch key springs and three energizer clutch

keys and are retained as an assembly on the main shaft

by a snap ring. The transmission may be used as an aid

in deceleration by downshifting in sequence without

double-clutching or any gear clashing. Reverse is not

synchronized, however, it is a helical gear to insure

quiet operation.

MAINTENANCE AND ADJUSTMENTS

Refer to similar procedures under the 3-speed Saginaw

Transmission Section for—Column Mounted Shift Linkage

Adjustment, Speedometer Driven Gear and Oil Seal Re-

placement, Extension Oil Seal Replacement and Trans-

mission Replacement. ~~

Camaro and Corvette Floor Shift Linkage Adjustment

(Fig.
lc)

1.
Set Lever (L), (K) in neutral position.

2.
Move Lever Assembly (A) and Levers (C), (D) to

neutral position and insert Locating Gauge (B) into

control Lever Bracket Assembly.

3.,
Install Rod (H) with Retainer (M) on Lever (L).

4.
With two Jam Nuts (G), (E) and Swivel (F) loose on

Rod (H) insert and attach Swivel with Retainer (N)

to Lever (D).

5.
Repeat steps 3 and 4 for Rod (J) and Levers (C
&
K).

6. Remove' Locating Gauge and check shift to insure

proper operation.

SIDE COVER ASSEMBLY

Removal

1.
Drain transmission and disconnect control rod and

cross shaft from side cover levers. *

2.
Remove nine cap screws securing the transmission

side cover assembly to transmission, case and re-

move cover assembly, shifting forks, and gasket.
Disassembly (Fig. 2C) '

1.
Remove shifting forks from shift lever assemblies.

2.
Remove nut and lock washer from each shift lever

shaft.

3.
Remove outer shift levers and lightly tap shift lever

shafts from assembly.

4.
Remove two steel balls, poppet spring, interlock pin

and interlock sleeve from cover.

5.
Remove "O" ring seals from shift lever shafts.

Assembly (Fig. 2C)

1.
Install new "O" ring seals to shift lever shafts.

2.
Install low and reverse shifter shaft and plate as-

sembly to cover.

3.
Place shifter shaft and plate assembly in neutral po-

sition, middle detent, and install interlock sleeve,

ball, poppet spring and interlock pin.

4.
Install remaining poppet ball and then install second

and third shifter shaft and plate assembly.

NOTE: Installation is easiest if shifter shaft

and plate assembly passes over ball in its neu-

tral position.

5.
Check clearance between end of interlock sleeve and

shifter shaft and plate cams when one plate is in

neutral and the other is shifted into gear position.

CHEVROLET CHASSIS SERVICE MANUAL

CLUTCH AND TRANSMISSIONS 7-16

FOUR-SPEED TRANSMISSION (MUNCIE)

INDEX

Page

General Description 7-16

Maintenance and Adjustments 7-16

Shift Linkage Adjustment 7-16

Gearshift Lever Reverse Blocker Cable 7-17

Replacement . 7-17

Adjustment 7-17

Speedometer Driven Gear and Oil Seal 7-19

Replacement 7-19

Transmission Side Cover 7-19

Removal 7-19
Page

Disassembly 7-19

Assembly 7-19

Installation . 7-19

Extension Oil Seal ......... 7-19

Replacement 7-19

Component Parts Replacement 7-20

Transmission Replacement 7-20

Removal from Vehicle , 7-20

. Installation in Vehicle . . . 7-20

GENERAL DESCRIPTION

The four-speed synchromesh transmission incorpo-

rates helical gears throughout specially designed to pro-

vide high torque capacity without additional weight, and

gear teeth proportioned to operate at high speeds with

neither excessive heat generation nor excessive fric-

tional losses. Shafts, bearings, high capacity clutches

and other precision parts are held to close limits, pro-

viding proper clearances necessary for durability during

extended heavy usage.

The main drive gear is supported by a heavy-duty ball

bearing at the front end of the transmission case and is

piloted at its front end in an oil impregnated bushing

mounted in the engine crankshaft. The front end of the

mainshaft is piloted in a row of roller bearings set into

the hollow end of the main drive gear and the rear end

is carried by a heavy-duty ball bearing mounted at the

rear end of the transmission case in a retainer casing.

The counter gear is carried on a double row of rollers

at both ends while thrust is taken on thrust washers lo-
cated between the ends of the gear and the thrust bosses

in the case.

The two-piece reverse idler gear is carried on bronze

bushings while thrust is taken on thrust washers located

between the front of the gear and the back of the reverse

idler thrust boss and between the rear of the gear and the

reverse idler shaft boss in the case extension.

Gearshifting is manual through shift control rods to the

transmission cover shifter levers for first through fourth

gears,
and to the reverse lever located in the case ex-

tension. The shifter lever to the rear of the transmis-

sion cover controls first and second gears while the

lever to the front controls third and fourth gears. All

four forward gears are fully synchronized. The trans-

mission may be used as an aid in deceleration by down-

shifting in sequence without double clutching. Reverse is

not synchronized, however, it is a helical gear to insure

quiet operation.

MAINTENANCE AND ADJUSTMENTS

SHIFT LINKAGE ADJUSTMENT (EXC. CORVETTE

AND CAMARO) (Fig. 1m)

1.
Set Transmission Levers (M), (P) and (S) in neutral

detent position.

2.
Move Shift Lever (A) to neutral detent position and

insert a Locating Gauge (1/8" thick by 41/64" (.646)

wide and 3" long) (B) into Control Lever Bracket

Assembly slot.

3.
Install Rod (V) with retainer on Lever (D).

4.
Maintaining Lever (D) against Locating Gauge, ad-

just Clevis (T) at Lever (S) until clevis pin freely

passes through holes in Clevis and Lever.

5. Install clevis pin, washer, and cotter pin. Tighten

Jam Nut (U) against Clevis.

6. Install Rod (H) with retainer on Lever (W).

7. With Jam Nuts (J) and (L) and Swivel (K) loose on

Rod (H), insert and attach Swivel with washer and

retainer to Lever (M).

8. Maintaining Lever (W) against Locating Gauge (B)

and while holding Swivel (K), run Jam Nut (J) against

Swivel until Nut contacts Swivel. Then tighten Jam

Nut (L) against Swivel.

9. Install Rod (R) with retainer on Lever (P).

10.
With Jam Nuts (E) and (G) and Swivel (F) loose on

Rod (R), insert and attach Swivel with retainer to
Lever (C).

11.
Maintaining Lever (C) against Locating Gauge (B) and

while holding Swivel (F), run Jam Nut (G) against

Swivel until Nut contacts Swivel. Then tighten Jam

Nut (E) against Swivel.

12.
Remove Locating Gauge and check shifts to insure

proper operation. Readjust clevis and swivels if

necessary.

NOTE:
Control rods may be attached to trans-

mission shift lever lower holes, to reduce shift

lever travel, for a "faster shift" adjustment op-

tion.
Increased shifting effort is required when

control rods are installed in this "short throw"

position.

CORVETTE AND CAMARO SHIFT LINKAGE

ADJUSTMENT (Fig. 2M)

1.
Set Transmission Shift Levers in neutral position.

2.
Move Shift Lever (A) to neutral position and insert

Locating Gauge (C) into control Lever Bracket As-

sembly (B).

3.
Install Reverse Rod (J) with Retainer on Lever (O).

4.
With two Jam Nuts and Swivel loose on Rod (J) insert

and attach Swivel with Retainer to Lever (D).

CHEVROLET CHASSIS SERVICE MANUAL

CLUTCH
AND
TRANSMISSIONS
7-20

COMPONENT PARTS REPLACEMENT

3.

4.

5.

6.
TRANSMISSION REPLACEMENT
(EXC.
CORVETTE)

Removal From Vehicle

1.
Remove shift lever trim plate and dust boot.

Remove shift lever assembly.

Raise vehicle
to
desired working height.

Disconnect
the
speedometer cable from speedometer

driven gear fitting.
.
~
. •

Remove propeller shaft, then support engine
at the

oil
pan
rail with
a
jack
or
other suitable support

capable
of
supporting
the
engine when transmission

is removed.

Disconnect shift lever bracket assembly from exten-

sion
and
remove
all 3
transmission shifter levers

from shifter shafts, (leave linkage connected
to

levers)
and
remove bracket assembly levers
and

linkage.

Remove extension mount7 to-crossmember attaching

bolts.

Loosen transmission crossmember
and
move rear-

ward
or
remove.

Remove
the
transmission-to-clutch housing retaining

bolts
and
install two guide pins, J-1126,
in
top holes.

Slide
the
transmission straight back until
the
input

shaft
is
free
of
splines
in the
clutch disc.

Slide
the
transmission rearward
to
allow sufficient

clearance
of
input shaft
and
clutch housing. Then tilt

input shaft
end of
transmission downward and with-
8.

9.

10.

11.
draw transmission from vehicle.

installation
to
Vehicle

1.
Raise transmission
and
rotate
as
necessary-to start

input shaft into clutch disc
and
slide transmission

forward until
it
bottoms against clutch housing.
Re-

move guide pins.

2.
Install
the
transmission-to-clutch housing retaining

bolts.
Torque
all
four retaining bolts
to 50 ft. lbs.

3.
Raise engine
and
position extension mount
to
cross-

member,
and
loosely install
the
retaining bolts.

Tighten crossmember
to
frame retaining bolts.

4.
Remove temporary support from engine, and torque

the extension mount retaining bolts.

5. Install propeller shaft.

6. Install control lever bracket assembly
to
transmis-

sion extension
and
connect shifter levers
to
shifter

shafts.

7. Fill transmission
to
level
of
filler plug hole with

correct lubricant specified
in
Section
0.

8. Lower vehicle and install shift lever assembly, check

shift pattern and adjust linkage
as
required.

9. Install trim plate and dust boot.

CORVETTE TRANSMISSION REPLACEMENT

Refer
to
similar procedure under 3-Speed Corvette

Transmission.

FOUR-SPEED (SAGINAW) TRANSMISSION

INDEX

Page

General Description
7-20

Maintenance
and
Adjustments
. . 7-21

Shift Linkage Adjustment.
. 7-21

Speedometer Driven Gear
and

Oil Seal ................
(See
Muncie 4-Speed)

Side Cover
7-22
Page

Removal
. . , 7-22

Disassembly
. . 7-22

Assembly
. . . 7-22

Installation
. 7-22

Extension
Oil
Seal
(See
Muncie 4-Speed)

Transmission Replacement (See Muncie 4-Speed)

GENERAL DESCRIPTION

The Saginaw four speed fully synchronized
(all
forward

gears) transmission incorporates helical drive gears

throughout.

The main drive gear
is
supported
by a
ball bearing
at

the front
end of the
transmission case and
is
piloted
at its

front
end in an oil
impregnated bushing mounted
in the

engine crankshaft.
The
front
end of the
mainshaft
is

piloted
in a row of
roller bearings
set
into
the
hollow
end

of
the
main drive gear
and the
rear end
is
carried
by a

ball bearing mounted
in the
front
of the
extension housing.

The countergear
is
carried
on a
single
row of
rollers

at both ends while thrust
is
taken on thrust washers
lo-

cated between
the
ends
of the
gear and
the
thrust bosses

in
the
case. Ah anti-rattle plate assembly
at the
front
of

the countergear provides
a
constant spring tension
be-

tween
the
counter
and
clutch gears
to
reduce torsional

vibrations.
The
sliding reverse idler gear
is
carried
on

a bushing finish bored
in
place.
It
rotates
on a
short

idler shaft retained by
a
woodruff
key.

The synchronizer assemblies consist
of a
clutch
hub,

clutch sleeve,
two
clutch
key
springs and three energizer

clutch keys
and are
retained
as an
assembly on
the
main

shaft
by a
snap ring.
A great deal
of
similarity
and
interchangeability
now

exists between
the new 3 and
4-speed Saginaw trans-

missions.

However,
the
synchronizer assembly
at the
front
of the

mainshaft
is
used
for the
third and fourth rather than
the

second
and
third shift.
The
synchronizer assembly
at

the rear
of the
mainshaft
is
used
for the
first and second

rather than
the
first
and
reverse shift. Gear teeth
cut

in
the
first and second synchronizer sleeve (reverse gear)

distinguish
it
from
the
third
and
fourth synchronizer

sleeve.

Starting from
the
front, gears
on the
mainshaft
are

third, second
and
first rather than second, first and
re-

verse.
A
fourth blocker ring
is
used between
the 1-2

synchronizer assembly
and
first gear
on the
four-speed

transmissions.

The cover
on the new
four-speed transmission
is lo-*

cated
on the
left-hand side
of the
case.
It is
similar
to

the three-speed cover with
the
addition
of a
reverse

shifter shaft assembly, detent ball
and
detent spring.

Disassembly
and
assembly procedures
are
covered
in

this section.

CHEVROLET CHASSIS SERVICE MANUAL

CLUTCH AND TRANSMISSIONS 7-21

MAINTENANCE AND ADJUSTMENTS

SHIFT LINKAGE ADJUSTMENT

(CHEVROLET & CHEVELLE)

1.
Set Lever (L) (M) and (P) in neutral detent position.

2.
Move Lever Stud (A) to neutral detent position and

insert Locating Gauge (B) into Control Lever Bracket

Assembly.

3.
Install Reverse Rod (H) with retainer on Lever (T).

4.
Maintaining Lever (T) against Locating Gauge, Adjust

Clevis (R) at Lever (P) until Clevis Pin freely passes

through holes in Clevis (R) and Lever (P).

5.
Install Clevis Pin, Washer and Cotter Pin; tighten

Nut (S) against Clevis (R).

6. Install Rod (K) with retainer on Lever (C).

7.
Maintaining Lever (C) against Locating Gauge, adjust

Clevis (N) at Lever (M) until Clevis Pin freely

passes through holes in Clevis (N) and Lever (M).

8. Install Clevis Pin, Washer and Cotter Pin; tighten

Nut (O) against Clevis (N).

9. Install Rod (J) with retainer on Lever (L).

10.
With two Jam Nuts (G), (E) and Swivel (F) loose on

Rod (J) insert and attach Swivel (F) with retainer to

Lever (D).

11.
Maintaining Lever (D) against Locating Gauge (B)

while holding Swivel (F) run Jam Nut (G) against

Swivel (F) then tighten other Jam Nut (E) against

swivel.

12.
Remove Locating Gauge and check shifts to insure

proper operation, readjust if necessary.

SHIFT LINKAGE ADJUSTMENT (CHEVY II)

1.
Set Levers (H) (R) and (T) in neutral detent position.
2.
Move Lower Control Lever (A) to neutral detent po-

sition and insert Locating Gauge (B) into Control

Lever Bracket Assembly.

3.
Install Reverse Control Rod (G) with retainer on

Lever (X).

4.
Maintaining Lever (X) in neutral position with Locat-

ing Gauge (B), Adjust Clevis (V) at lever (T) until

Clevis Pin freely passes through hole in Clevis (V)

and Lever (T).

5.
Install Clevis Pin, Washer and Cotter Pin. Tighten

Jam Nut (W) to specified torque against Clevis.

6. Install Control Rod (F) with retainer on Lever (C).

7.
Maintaining Lever (C) in neutral position with Locat-

ing Gauge (B), Jam Nuts (M and S) and Swivel (N)

loose on Rod (F), attach to Lever (R) with retainer.

8. While holding Swivel (N) run Jam Nut (M) against

Swivel (N) and tighten Jam Nut (S) against Swivel (N).

9. Install Rod (E) with retainer on Lever (D).

10.
Maintaining Lever (D) in neutral position with Locat-

ing Gauge (B) and Jam Nut (J and L) and Swivel (K)

loose on Rod (E) attach to Lever (H) with retainer.

11.
While holding Swivel (K) run Jam Nut (J) against

Swivel (K) and tighten Jam Nut (L) against Swivel (K).

12.
Remove Locating Gauge (B) and shift to insure proper

operation. Readjust clevis and swivels if necessary.

SHIFT LINKAGE ADJUSTMENT

(CAMARO AND CORVETTE)

1.
Set Transmission Shift Levers in neutral position.

2.
Move Lever Arm (A) and Lever (C) (D) and (E) to

neutral position and insert Locating Gauge (B) into

Control Lever Bracket Assembly.

N

f E

Fig.
IX - Shift. Linkage (Chevrolet & Chevelle)

CHEVROLET CHASSIS SERVICE MANUAL

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

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

CLUTCH AND TRANSMISSIONS 7-37

LI.
- LI Range can be selected at any vehicle speed,

and the transmission will shift to second gear

and remain in second until vehicle speed is re-

duced to approximately 40 MPH, .depending on

axle ratio. LI Range position prevents the trans-

mission from shifting out of first gear.
It is very important that any communication concerning

the Turbo Hydra-Matic always contain the transmission

serial number and that all transmission parts returned

to Chevrolet Motor Division always be tagged with the

transmission serial number.

MAINTENANCE AND ADJUSTMENTS

TRANSMISSION FLUID

Transmission fluid level should be checked with trans-

mission warm and selector lever in "P" Park position,

every time engine oil level is checked or as specified in

Section 0 when engine oil is changed.

CAUTION: Since the Turbo Hydra-Matic trans-

mission is very sensitive to oil level, special

precautions should be taken when checking the

oil level, to insure against an overfifE

Transmission fluid should be changed as specified in

Section 0.

FLUID LEVEL INDICATOR

The fluid level indicator is located in the filler pipe at

the right rear corner of the engine. To bring the fluid

level from the add mark to the full mark add 1 pint.

Fluid level should be to the full mark with transmission

at normal operating temperature. With cold fluid the

level should be at the add mark or slightly below.

SHIFT CONTROL LINKAGE ADJUSTMENT

Adjust linkage as shown below and in Figure 2.

1.
The shift tube and lever assembly must be free in the

mast jacket See Section 9 for alignment of steering

column assembly if necessary.

2.
To check for proper shift linkage adjustment, lift the

transmission selector lever towards the steering

wheel. Allow the selector lever to be positioned in

drive (D) by the transmission detent.

NOTE: Do not use the indicator pointer as a

reference to position the selector lever. When

performing linkage adjustment, pointer is ad-

justed last.

3.
Release the selector lever. The lever should be in-

hibited from engaging low range unless the lever is

lifted.

4.
Lift the selector lever towards the steering wheel,

and allow the lever to be positioned in neutral (N) by

the transmission detent.

5.
Release the selector lever. The lever should now be

inhibited from engaging reverse range unless the

lever is lifted.

6. A properly adjusted linkage will prevent the selector

lever from moving beyond both the neutral detent,

and the drive detent unless the lever is lifted to pass

over the mechanical stop in the steering column.

See schematic diagram.

7.
In the event that an adjustment is required, place the

selector lever in drive (D) position as determined by

the transmission detent. See Steps 2 and 3.

8. Loosen the adjustment swivel at the cross-shaft, and
rotate the transmission lever so that it contacts the

drive stop in the steering column.

9. Tighten the swivel and recheck the adjustment. See

Steps 2 and 6. -

l(h Readjust indicator needle if necessary to agree with

the transmission detent" positions. See Section 9.

11.
Readjust neutral safety switch if necessary to pro-

vide the correct relationship to the transmission de-

tent positions. See Section 12.

12.
When properly adjusted the following conditions must

be met by manual operation of the steering column

shift lever:

a. From reverse to drive position travel, the trans-

mission detent feel must be noted and related to

indicated position on dial.

b.
When in drive and reverse positions, pull lever

rearward (towards steering wheel) and then re-

lease. It must drop back into position with no

restrictions.

NEUTRAL SAFETY SWITCH ADJUSTMENT

The neutral safety switch must be adjusted so that the

car will start in the park or neutral position, but will not

start in the other positions. For replacement refer to

Section 12 of this Manual.

DRAINING AND REFILLING TRANSMISSION

Drain oil immediately after operation before it has had

an opportunity to cool.

To drain oil proceed as follows:

1.
Remove bottom pan attaching screws, pan, and gas-

ket.

2.
Remove oil strainer. Remove "O" ring seal from

pick-up pipe and discard.

3.
Discard strainer if dirty.

4.
Install new "O" ring seal on pick-up pipe and install

strainer and pipe assembly.

5.
Thoroughly clean bottom pan.

6.. Affix new gasket to bottom pan with petroleum jelly.

7.
Install bottom pan with attaching screws and torque

to specifications;

8. If only the pan has been removed, pour approximately

7-1/2 pints of fluid into the transmission. If the

valve body has also been removed use 9-1/2 pints.

After a complete overhaul approximately 19 pints

are required. Be sure container, spout, or funnel is

clean.

9. Start engine and let idle (carburetor off fast idle

step).
Place selector lever in P position and apply

hand brake.

10.
With transmission warm (approximately 150°F), add

fluid to bring level to full mark on indicator.

CAUTION: Do not overfill. Foaming will re-

sult.

CHEVROLET CHASSIS SERVICE MANUAL