check engine FORD MUSTANG 1969 Volume One Chassis

05-03-06
Clutch

05-03-06

8. Remove the starter cable then

remove the starter motor from the fly-

wheel housing.

9. Remove the bolts that secure the

engine rear plate to the front lower

part of the flywheel housing.

10.
Remove the flywheel housing

lower cover (390 CID housing only).

11.
Remove the bolts that attach

the housing to the cylinder block.

12.
Move the housing back just far

enough to clear the pressure plate,

then move it to the right to free the

pivot from the clutch equalizer bar. Be

careful not to disturb the linkage and

assist spring.

13.
Loosen the six pressure plate

cover attaching bolts evenly to release

the spring tension. If the same pres-

sure plate and cover is to be installed

after the clutch is overhauled, mark

the cover and flywheel so that the

pressure plate can be installed in the

same position.

14.
Remove the pressure plate and

the clutch disc from the flywheel.

CLUTCH INSTALLATION

1.
Install the clutch release lever if

it was removed.

2.
Place the clutch disc, and pres-

sure plate assembly in position on the

flywheel. Start the cover attaching

bolts to hold the pieces in place, but

do not tighten them. Avoid touching

the clutch disc facing, dropping the

parts or contaminating them with oil

or grease as clutch chatter may result.

3.
Align the clutch disc with the

tool shown in Fig. 7, and alternately

tighten the bolts a few turns at a time

until they are all tight. Then torque

the six pressure plate cover attaching

bolts to specification before removing

the tool.
4.
Apply a light film of grease

(C3VY-19586-A) to the outside diam-

eter of the transmission front bearing

retainer. Apply a light film of grease

(C3VY-19586-A) to both sides of the

release lever fork where it contacts the

release bearing bore spring clips.

Apply a light film of grease to the re-

lease bearing surface that contacts the

pressure plate release fingers. Fill the

grease groove of the release bearing

hub with lithium base grease (C3VY-

19586-A). Clean all excess grease

from inside the bore of bearing hub.

Excess grease will be forced onto the

spline by the transmission input shaft

bearing retainer and will contaminate

the clutch disc. Also, place the release

bearing and hub on the release lever.

5.
Make certain that the flywheel

housing and the cylinder block mount-

ing surfaces are clean. Position the

felt washer on the pivot in the fly-

wheel housing. Slip the pivot into the

clutch equalizer shaft being careful

not to disturb the linkage and at the

same time position the housing on the

dowels in the cylinder block. Install

and torque the attaching bolts to spec-

ification.

6. Install the starting motor and

connect the cable.

7.
The mounting surfaces of the

transmission and the flywheel housing

must be free of dirt, paint, and burrs.

Install two guide pins in the flywheel

housing lower mounting bolt holes.

Move the transmission forward on the

guide pins until it is tightly positioned

against the flywheel housing.

8. Install the two upper mounting

bolts.
Then, remove the guide pins

and install the two lower mounting

bolts.
Torque all the bolts to specifica-

tion.

9. Raise the rear of the engine and
install the crossmember. Install and

torque the crossmember attaching

bolts to specifications, then lower the

engine.

10.
Install the extension housing-

to-engine rear support attaching bolts.

Torque the bolts to specification.

11.
Remove the transmission jack

and connect the parking brake cable.

12.
If the vehicle is equipped with a

four-speed transmission, connect the

gear shift linkage control bracket to

the extension housing.

13.
Connect the gear shift rods to

the transmission. Adjust the shift link-

age as required.

14.
Connect the release lever retain-

ing spring. Install the flywheel housing

cover (390 CID housing only).

15.
Remove the tool from the

transmission output shaft and install

the drive shaft.

16.
Check the clutch pedal free

travel.

CLUTCH ARBOR CLUTCH DISC

PRESSURE PLATE

C 1788-A

FIG. 7—Installing Clutch Disc —

Typicalprocarmanuals.com

06-02-02
Ford Design Three Speed Transmission

06-02-02

DESCRIPTION

DESCRIPTION

The RAN and RAT Model three-

speed transmission (Fig. 1) are used

on models having 170, 200, 240, 250,

302,
351 and 390 C.I.D. engines. The

specifications of this section, Part 6-4,

lists the transmission model numbers

and vehicles in which they are used.

A transmission service identification
tag is located on the right side of the

case at the front (Fig. 2). The first

line on the tag will show the transmis-

sion model and service identification

code when required. The second line

will show the transmission serial num-

ber. Additionally, a driveline compo-

nent identification tag is attached to

the upper right side of the transmis-

sion case.
This transmission is of the fully

synchronized type, with all gears ex-

cept the reverse gear and sleeve being

in constant mesh. All forward-speed

changes are accomplished with syn-

chronizer sleeves.

The forward-speed gears are

helical-cut and are in constant mesh.

Gears used in the reverse gear train

are spur-cut and are not synchronized.

C2O87-A

FIG.
1—Three-Speed
Transmission—Typical
TRANS.
MODEL

SERIAL
NO.

C 2089-A

FIG.
2—Transmission
Identification

Tag

IN-VEHICLE ADJUSTMENTS
AND
REPAIRS

GEAR SHIFT LINKAGE

ADJUSTMENT—COLUMN

MOUNTED

1. Place the gear shift lever in the

neutral position.

2.
Loosen the two gear shift rod

adjustment nuts.

3.
Check shift levers on transmis-

sion to be in neutral position.

4.
Insert a 3/16-inch diameter

alignment tool through the first and

reverse gear shift lever, the second and

third gear shift lever and both holes

in the lower casting (Fig. 3). An align-

ment tool can be made from 3/16

inch drill rod bent to an L shape.

The extensions should be 1 inch and 2

inches from the elbow. The short end

of the tool should be inserted into the

alignment holes.

5.
Tighten the two gear shift rod

adjustment nuts.

6. Remove the alignment tool from

the levers.

7.
Start the engine and shift the se-

lector lever to each position to make

sure it operates freely.
FIG.
3—Gearshift
Linkage Adjustment—Typicalprocarmanuals.com

06-03-03
Ford Design Four-Speed Transmission
06-03-03

cable from the equalizer lever and sep-

arate the lever from the crossmember.

5.
Remove the hairpin retainer se-

curing the cable to the transmission

rear support crossmember, and then

pull the cable assembly forward and

out of the crossmember.

6. Remove the retaining clip, flat

washer, and spring washer that se-

cures the shift rods to the shift levers.

7.
Remove the bolts that attach the

shift linkage control bracket to the ex-

tension housing and position the as-

sembly out of the way.

8. Support the engine with a trans-

mission jack and remove the extension

housing-to-engine rear support attach-

ing bolts.

9. Raise the rear of the engine high

enough to remove the weight from the

crossmember. Remove the bolts re-

taining the crossmember to the frame

side supports and remove the

crossmember.

10.
Support the transmission on a

jack and remove the bolts that attach

the transmission to the flywheel hous-

ing.

11.
Move the transmission and jack

rearward until the transmission input

shaft clears the flywheel housing. If

necessary, lower the engine enough to

obtain clearance for transmission re-

moval.

Do not depress the clutch pedal

while the transmission is removed.
INSTALLATION

1.
Make sure that the mounting

surface of the transmission and the

flywheel housing are free of dirt,

paint, and burrs. Install two guide

pins in the flywheel housing lower

mounting bolt holes. Move the trans-

mission forward on the guide pins

until the input shaft splines enter the

clutch hub splines and the case is posi-

tioned against the flywheel housing.

2.
Install the two upper transmis-

sion to flywheel housing, mounting

bolts snug, and then remove the two

guide pins. Install the two lower

mounting bolts. Torque all mounting

bolts to specifications.

3.
Raise the rear of the engine and

install the crossmember. Install and

torque the crossmember attaching

bolts to specifications, then lower the

engine.

4.
With the transmission extension

housing resting on the engine rear

support, install the transmission ex-

tension housing attaching bolts. Tor-

que the bolts to specifications.

5.
Position the shift linkage control

bracket to the extension housing and

install the attaching bolts.

6. Secure each shift rod to its re-

spective lever with the spring washer,

flat washer, and retaining pin.

7.
Guide the parking brake cable

assembly through the hole in the
transmission rear support crossmemb-

er. Secure the cable assembly to the

crossmember with the hair pin retain-

er.

8. Insert the parking brake front

cable in the equalizer and install the

equalizer in the bracket on the

crossmember. Secure the parking

brake rear cable to the equalizer.

9. Connect the speedometer cable

to the extension housing.

10.
Remove the extension housing

installation tool and slide the forward

end of the drive shaft over the trans-

mission output shaft. Connect the

drive shaft to the rear U-joint flange.

11.
Place both forward gear shift

levers and the reverse shift lever in the

neutral position and insert a 1/4 inch

diameter alignment tool in the shift

linkage alignment hole (Fig. 17). It

may be necessary to loosen the adjust-

ment nuts to install the alignment

tool. Adjust the linkage as necessary

and tighten the adjustment nuts to

specifications. Remove the alignment

tool.

12.
Fill the transmission to the

proper level with the specified lubri-

cant.

13.
Lower the car. Check tne shift

and crossover motion for full shift en-

gagement and smooth crossover oper-

ation.

MAJOR REPAIR OPERATIONS

DISASSEMBLY

1.
Mount the transmission in a

holding fixture and drain the lubri-

cant.

2.
Remove the cover attaching

screws from the case. Lift the cover

and gasket from the case.

3.
Remove the long spring that re-

tains the detent plug in the case (Fig.

4).
Remove the detent plug with a

small magnet.

4.
Remove the extension housing

attaching screws and lock washers.

Remove the housing and the gasket.

5.
Remove the input shaft bearing

retainer attaching screws. Slide the re-

tainer off the input shaft.

6. Support the countershaft gear

with a wire hook. Working from the

front of the case, push the counter-

shaft out the rear of the case as shown

in Fig. 3. Lower the countershaft to

the bottom of the case with the wire

hook. Remove the hook.
Tool-T64P-711hA

COUNTERSHAFT

C2073-A

FIG. 3—Removing Countershaft

From Case

7.
Place the first and second-speed

gear shift lever and the reverse shift

lever in the neutral position. Place the

third and fourth-speed gear shift lever

in the third-speed position.

8. Remove the attaching screw

from the third and fourth-speed shift

fork. Tap on the inner end of the shift

rail to unseal the expansion plug from
the front of the case. Then withdraw

the third and fourth-speed shift rail

from the front of the case. Do not

lose the interlock pin from the shift

rail.

9. Remove the set screw from the

first and second-speed shift fork.

Slide the first and second-speed shift

rail out the rear of the case.

10.
Remove the interlock plug and

the detent plug from the top of the

case (Fig. 4) with a magnet.

11.
On some models, remove the

snap ring that secures the speedometer

drive gear to the output shaft. Slide

the gear off the shaft, then remove the

speedometer gear drive ball. On mod-

els equipped with the new design re-

tainers, depress the tang on the speed-

ometer drive gear retaining clip and

slide the speedometer gear off the

shaft. (Fig. 5).

12.
Remove the snap ring that se-

cures the output shaft bearing to the

shaft.procarmanuals.com

07-01-01

07-01-01

*.v:;V*>
-"^g&ly-

'y.y... -4^*:
GROUP

7

PART
7-1
PAGE

General Transmission Service
07-01-01

PART
7-2

C4 Automatic Transmission
07-02-01

PART
7-3

FMX Transmission
07-03-01
PART
7-4

C6 Automatic Transmission
....

PART
7-5

Specifications
PAGE

07-04-01

07-05-01

TRANSMISSION

CODE
TRANSMISSION

TYPE

AUTOMATIC
(C4)

U AUTOMATIC
(C6)

X AUTOMATIC
(FMX)

Z AUTOMATIC
(C6
SPECIAL)

D2040-A

FIG. 1—Typical Warranty Plate—Transmission Identification

PART
7-1
General
Transmission
Service

COMPONENT INDEX

AIR PRESSURE CHECKS

ANTI-STALL DASHPOT CLEARANCE

CHECK

(Engine Compartment)

CASE (Transmission)

Inspection

CONTROL PRESSURE CHECK

CONTROL VALVE BODY

Inspection

CONVERTER

Checking

Cleaning

DRAIN AND REFILL (Transmission)

ENGINE IDLE SPEED CHECK

EXTENSION HOUSING INSPECTION

FLUID AERATION CHECK
MODEL APPLICATION
All
Models

01-06

01-04

01-17

01-05

01-17

01-04

01-11

01-08

01-04

01-15

01-03
Ford
Mercury
Meteor
Cougar
Fairiane
Falcon
Montego
Mustang
Lincoln-
Continental
Thunderbird
Continental-
Mark
III

A page number indicates that the item
is for
the vehicle listed
at
the head
of
the column.

N/A indicates that the item
is not
applicable
to
the vehicle listed.
procarmanuals.com

07-01-03

General Transmission Service

07-01-03

COMPONENT INDEX

FMX Transmission

REAR SUPPORT (FMX)

Inspection

SHIFT POINT CHECKS

STATOR ONE-WAY CLUTCH CHECK

STATOR TO IMPELLOR INTERFERENCE

CHECK

STATOR TO TURBINE INTERFERENCE

CHECK

TRANSMISSION CLEANING

TURBINE AND STATOR END PLAY

CHECK

VACUUM DIAPHRAGM ADJUSTMENT

Altitude Compensating Type

Non-Altitude Compensating Type

VACUUM UNIT CHECK

Altitude Compensating Type

Non-Altitude Compensating Type
MODEL APPLICATION
All
Models

01-06

01-12

01-12

01-12

01-11

01-12
Ford
01-17

01-16

N/A

01-08

N/A

01-05
Mercury
N/A

N/A

N/A

01-08

N/A

01-05
Meteor
01-17

01-16

N/A

01-08

N/A

01-05
Cougar
01-17

01-16

N/A

01-08

N/A

01-05
Fairlane
01-17

01-16

N/A

01-08

N/A

01-05
Falcon
N/A

N/A

N/A

01-08

N/A

01-05
Montego
01-17

01-16

N/A

01-08

N/A

01-05
Mustang
01-17

01-16

N/A

01-08

N/A

01-05
Lincoln-
Continental
N/A

N/A

01-09

N/A

01-06

N/A
Thunderbird
N/A

N/A

01-09

N/A

01-06

N/A
Continental-
Mark
III
N/A

N/A

01-09

N/A

01-06

N/A

A page number indicates that the item is for the vehicle listed at the head of the column.

N/A indicates that the item is not applicable to the vehicle listed.

Three different three-speed trans-

missions are used. The C4 Automatic,

C6 Automatic and the FMX Auto-

matic. Part 7-1 covers testing, com-
mon adjustments and repairs, and

cleaning and inspection for the three

types of transmissions. Where there
are differences in procedures or speci-

fications, the type of transmission af-

fected will be designated.

l
AUTOMATIC TRANSMISSION TESTS

When diagnosing transmission

problems, refer to the Ford Car and

Truck Diagnosis Manual for the de-

tailed information on the items that

could be causing the problem.

The following preliminary checks

should be made before proceeding

with other diagnosis checks.

TRANSMISSION FLUID LEVEL

CHECK

1.
Make sure that the vehicle is

standing level. Then firmly apply the

parking brake.

2.
Run the engine at normal idle

speed. If the transmission fluid is cold

run the engine at fast idle speed

(about 1200 rpm) until the fluid reach-

es its normal operating temperature.

When the fluid is warm, slow the en-

gine down to normal idle speed.

3.
On a vehicle equipped with a

vacuum brake release, disconnect the

release line and plug the end of the
line;
otherwise the parking brake will

not hold the transmission in any drive

position.

4.
Shift the selector lever through

all positions, and place the lever at P.

Do not turn off the engine during the

fluid level checks.

5.
Clean all dirt from the transmis-

sion fluid dipstick cap before remov-

ing the dipstick from the filler tube.

6. Pull the dipstick out of the tube,

wipe it clean, and push it all the way

back into the tube. Be sure it is prop-

erly seated.

7.
Pull the dipstick out of the tube

again, and check the fluid level. The

fluid level should be above the ADD

mark. If necessary, add enough fluid

to the transmission through the filler

tube to bring the level between the

ADD and FULL marks on the dip-

stick. Do not overfill the transmission.

Install the dipstick, making sure it is

fully seated in the tube.
8. Connect the vacuum brake re-

lease line if so equipped, and test it

for proper operation.

FLUID AERATION CHECK

A fluid level that is too high will

cause the fluid to become aerated:

Aerated fluid will cause low control

pressure, and the aerated fluid may be

forced out the vent.

Check the transmission fluid level.

Low fluid level can affect the opera-

tion of the transmission, and may in-

dicate fluid leaks that could cause

transmission damage.

TRANSMISSION FLUID

LEAKAGE CHECKS

Check the speedometer cable con-

nection at the transmission. Replace

the rubber seal if necessary.

Leakage at the oil pan gasket often

can be stopped by tightening the at-
procarmanuals.com

07-01-04
General Transmission Service

07-01-04

taching bolts to the proper torque. If

necessary, replace the gasket.

Check the fluid filler tube connec-

tion at the transmission case or pan.

If leakage is found here, install a new

O-ring or tighten the fitting to the

specified torque.

Check the fluid lines and fittings

between the transmission and the

cooler in the radiator tank for loose-

ness,
wear, or damage. If leakage can-

not be stopped by tightening a fitting,

replace the damaged parts.

Check the engine coolant in the ra-

diator. If transmission fluid is present

in the coolant, the cooler in the radia-

tor is probably leaking.

The cooler can be further checked

for leaks by disconnecting the lines

from the cooler fittings and applying

50-75 psi air pressure to the fittings.

Remove the radiator cap to relieve the

pressure build at the exterior of the oil

cooler tank. If the cooler is leaking

and will not hold this pressure the

cooler must be replaced. Cooler re-

placement is described in the Cooling

System Section of Group 11.

If leakage is found at either the

downshift control lever shaft or the

manual lever shaft, replace either or

both seals.

Inspect the pipe plug on the left

side of the transmission case at the

front. If the plug shows leakage, tor-

que the plug to specifications. If tight-

ening does not stop the leaks, replace

the plug. On a C6 transmission, a TV

pressure plug is also provided on the

right rear side of the case.

When converter drain plugs leak,

remove drain plugs with a six-point

wrench. Coat the threads with FoMo-

Co Perfect Seal Sealing Compound or

its equivalent, and install the plugs.

Torque the drain plugs to specifica-

tion. Fluid leakage from the converter

housing may be caused by engine oil

leaking past the rear main bearing or

from oil gallery plugs, or power steer-

ing oil leakage from steering system.

Be sure to determine the exact cause

of the leak before repair procedures

are started.

Oil-soluble aniline or fluorescent dyes

premixed at the rate of 1/2 teaspoon

of dye powder to 1/2 pint of transmis-

sion fluid have proved helpful in locat-

ing the source of the fluid leakage.

Such dyes may be used to determine

whether an engine oil or transmission

fluid leak is present or if the fluid in

the oil cooler leaks into the engine

coolant system. A black light, how-

ever, must be used with the fluorescent

dye solution.
DISHED OR

FLAT WASHER

" O.D.,
a" STEEL PLATE

5/8"X \W,

DRILL TO SUIT
HEX. HEAD SCREW

3/8"-24 X Vl

HEX. NUT W—
24

WELD

TOGETHER

WING
NUT

>/2"_13
THREAD

CHAIN,
10"
LONG
RUBBER PLUG

1
Vi" DIA. X 2"

LONG Vl"

HOLE THRU

APPROXIMATELY

40 DUROMETER
FLAT WASHER

Vs" O.D.

PLUG

VALVE
STANDARD BOLT

W-13
X 4Vl"

LONG SQUARE

THREAD
END

REMOVE HEAD

AND WELD
TO

WASHER

STANDARD 1/8" FITTING-87971-S FOR

RETAPPED DRAIN PLUG THREADS-USE

1/4" OVERSIZE FITTING-87973-S

D 1067-B
WELD TOGETHER

SECURELY—MUST

NOT LEAK

FIG. 2—Converter Leak Checking Tool

CONVERTER LEAKAGE

CHECK

If there are indications that the

welds on the torque converter are

leaking, the converter will have to be

removed and the following check

made before the unit is replaced.

A leak checking tool (Fig. 2) can be

made from standard parts. The tool

can be used to check all converters.

1.
Install the plug in the converter

(Fig. 3) and expand it by tightening

the wing nut. Attach the safety chains.

2.
Install the air valve in one of the

drain plug holes.

3.
Introduce air pressure into the

converter. Check the pressure with a

tire gauge and adjust it to 20 psi.

4.
Place the converter in a tank of

water. Observe the weld areas for

bubbles. If no bubbles are observed, it

may be assumed that the welds are

not leaking.

ENGINE IDLE SPEED CHECK

Check and, if necessary, adjust the

engine idle speed, using the procedure

given in Group 10.

If the idle speed is too low, the en-

gine will run roughly. An idle speed

that is too high will cause the vehicle

to creep, have harsh engagements and

harsh closed-throttle downshifts.
ANTI-STALL DASHPOT

CLEARANCE CHECK

After the engine idle speed has been

properly adjusted, check the anti-stall

dashpot clearance. Follow the proce-

dure given in Group 10 for checking

and adjusting this clearance.

MANUAL LINKAGE CHECKS

Correct manual linkage adjustment

is necessary to position the manual

valve for proper fluid pressure direc-

tion to the different transmission com-

ponents. Improperly adjusted manual

Tire Pressure Gauge

D1921-A

FIG. 3—Converter Leak Checking

Tool Installationprocarmanuals.com

07-01-05
General Transmission Service

07-01-05

linkage may cause crossleakage and

subsequent transmission failure. Refer

to Linkage Adjustments in Part 7-2,

7-3 or 7-4 for detailed manual linkage

adjustment procedures.

CONTROL PRESSURE

CHECK

When the vacuum diaphragm unit is

operating properly and the downshift

linkage is adjusted properly, all the

transmission shifts (automatic and

kickdown) should occur within the

road speed limits specified in Part 7-5.

If the shifts do not occur within

limits or the transmission slips during

shift point, the following procedure is

suggested to determine engine, trans-

mission, linkage, vacuum diaphragm

unit or valve body problems.

1.
Using the automatic transmis-

sion tester (Fig. 4), attach the tachom-

eter to the engine and the vacuum

gauge to the transmission vacuum line

at the vacuum unit (Fig. 5).

D 1823-A

. 4—Rotunda ARE-2905

Automatic Transmission Tester

T - FITTING
2.
Attach the pressure gauge to the

control pressure outlet at the trans-

mission (Figs. '., and 7).

3.
Firmly apply the parking brake

and start the engine.

On a vehicle equipped with a vacu-

um brake release, apply the service

brakes. The parking brake can not be

used because the brake automatically

VACUUM DIAPHRAGM UNIT

CLIP

I

| CONTROL PRESSURE TAKE-OFF HOLE

D2041-A

FIG. 6—Typical Vacuum

Diaphragm and Control Pressure

Connecting Point
releases when the transmission selec-

tor lever is moved to a drive position.

4.
Adjust the engine idle speed lo

the specified rpm. If the engine idle

speed cannot be brought within limits

by adjustment at the carburetor idle

adjustment screw, check the throttle

and downshift linkage for a binding

condition. If the linkage is satisfacto-

ry, check for vacuum leaks in the

transmission diaphragm unit (Fig. 8

or 9) and its connecting tubes and

hoses.
Check all other vacuum oper-

ated units (such as the power brake)

for vacuum leaks.

VACUUM UNIT CHECK

NON-ALTITIDE

COMPENSATING TYPE

To check the vacuum unit for dia-

phragm leakage, remove the unit from

the transmission. Use a distributor

D1840-A

FIG. 8—Testing Transmission

Vacuum Unit for Leakage

VACUUM DIAPHRAGM

D 1643 -C

FIG. 5—Typical Vacuum Test

Line Connections
FIG.
7—Vacuum
Diaphragm and Control and TV Pressure Connecting

Points—C6 Transmissionprocarmanuals.com

07-01-08
General Transmission Service

07-01-08

3.
Install the bench testing tool on

the transmission.

4.
Remove the
1/8-inch
pipe plug

at the transmission case. Turn the

front pump in a clockwise direction at

75-100 rpm until a regular flow of

transmission fluid leaves the hole in

the transmission case. This operation
bleeds the air from the pump.

5.
Install the pressure gauge (77820

or T57L-77820-A) as shown in Fig.

13.

PRESSURE TESTS

Turn the front pump at 75-100 rpm
and note the gauge readings. The

pressure readings on the bench test

must be within the limits as outlined

in Figure 13, for the engine idle check.

If pressure gauge readings are with-

in limits in all selector lever positions,

install the vacuum diaphragm control

rod unit.

COMMON ADJUSTMENTS AND REPAIRS

TRANSMISSION FLUID DRAIN

AND REFILL

Normal maintenance and lubrica-

tion requirements do not necessitate

periodic automatic transmission fluid

changes.

If a major repair, such as a clutch

band, bearing, etc., is required in the

transmission, it will have to be re-

moved for service. At this time the

converter, transmission cooler and

cooler lines must be thoroughly

flushed to remove any dirt.

When filling a dry transmission and

converter, install five quarts of fluid.

Start the engine, shift the selector

lever as outlined below, and check and

add fluid as necessary.

Following are the procedures for

partial drain and refill due to in-

vehicle repair operation.

C4 TRANSMISSION

1.
On PEA models, disconnect the

fluid filler tube from the transmission

oil pan to drain the fluid.

On PEB and PEE models, loosen

the pan attaching bolts to drain the

fluid from the transmission.

2.
When the fluid has stopped

draining from the transmission, re-

move and thoroughly clean the pan

and the screen. Discard the pan gas-

ket.

3.
Place a new gasket on the pan,

and install the pan on the transmis-

sion.

4.
On PEA models, connect the

filler tube to the pan and tighten the

fitting securely.

5.
Add three quarts of fluid to the

transmission through the filler tube.

6. Run the engine at idle speed for

about two minutes, and then run it at

fast idle speed (about 1200 rpm) until

it reaches it's normal operating temp-

erature. Do not race the engine.

7.
Shift the selector lever through

all the positions, place it at P, and

check the fluid level. The fluid level

should be above the ADD mark. If
necessary, add enough fluid io the

transmission to bring the level be-

tween the ADD and FULL marks on

che dipstick. Do not overfill the trans-

mission.

FMX OK C6

TRANSMISSION

1.
Raise the vehicle on a hoist or

jack stands.

2.
Place a drain pan under the

transmission.

3.
Loosen the pan attaching bolts

to drain the fluid from the transmis-

sion.

4.
After the fluid has drained to the

level of the pan flange, remove the

rest of the pan bolts working from the

rear and both sides of the pan to

allow it to drop and drain slowly.

5.
When the fluid has stopped

draining from the transmission, re-

move and thoroughly clean the pan

and the screen. Discard the pan gas-

ket.

6. Place a new gasket on the pan,

and install the pan on the transmis-

sion.

7.
Add three quarts of fluid to the

transmission through the filler tube.

8. Run the engine at idle speed for

about two minutes, and then run it at

fast idle speed (about 1200 rpm) until

it reaches normal operating tempera-

ture.
Do not race the engine.

9. Shift the selector lever through

all the positions, place it at P, and

check the fluid level. The fluid level

should be above the ADD mark. If

necessary, add enough fluid to the

transmission to bring the level be-

tween the ADD and FULL marks on

the dipstick. Do not overfill the trans-

mission.

OIL COOLER TUBE

REMOVAL AND INSTALLATION

When fluid leakage is found at the

oil cooler, the cooler must be re-

placed. Cooler replacement is de-

scribed in the Cooling System Section

of Group 11.
When one or more of the fluid

cooler steel tubes must be replaced,

each replacement tube must be fabri-

cated from the same size steel tubing

as the original line.

Using the old tube as a guide, bend

the new tube as required. Add the

necessary fittings, and install the tube.

After the fittings have been tight-

ened, add fluid as needed, and check

for fluid leaks.

VACUUM DIAPHRAGM

ADJUSTMENT NON-ALTITUDE

COMPENSATING TYPE

The C4 and C6 transmissions are

equipped with an adjustable vacuum

diaphragm assembly. A similar ad-

justable diaphragm has been released

for service with the FMX transmis-

sion. However, the FMX service dia-

phragm is not interchangeable with

that used on C4 and C6 models.

The vacuum diaphragm assembly

has an adjusting screw in the vacuum

hose connecting tube (Fig. 14).

SPRING

SEAT

THIS CLEARANCE CHANGED

BY ADJUSTING SCREW

D1830-A

FIG. 14—Adjustable Vacuum Unit

The inner end of the screw bears

against a plate which in turn bears

against the vacuum diaphragm spring.

All readings slightly high or all

readings slightly low may indicate the

vacuum unit needs adjustment to cor-

rect a particular shift condition.procarmanuals.com

07-01-09

General Transmission Service

07-01-09

For example, on a C4 transmission,

if the pressure at 10 inches of vacuum

was 120 psi and the pressure at 1.0

inch of vacuum was 170 psi, and up-

shifts and downshifts were harsh, a di-

aphragm adjustment to reduce the di-

aphragm assembly spring force would

be required.

If the pressure readings are low, an

adjustment to increase diaphragm

spring force is required.

To increase control pressure, turn

the adjusting screw in clockwise to re-

duce control pressure, back the adjust-

ing screw out by turning it counte-

rclockwise. One complete turn of the

adjusting screw (360 degrees) will

change idle line control pressure ap-

proximately 2-3 psi. After the adjust-

ment is made, install the vacuum line

and make all the pressure checks as

outlined in the Specification Section.

The diaphragm should not be ad-

justed to provide pressure below the

ranges shown in the Specification Sec-

tion in order to change shift feel. To

do so could result in soft or slipping

shift points and damage to the trans-

mission.

ALTITUDE

COMPENSATING TYPE

The altitude—compensating di-

aphragm is provided with an adjust-

ment screw located in the vacuum

connecting tube (Fig. 15). The adjus-

table feature allows control and TV

pressures to be adjusted (within limits)

to correct soft or harsh shift feel.

Control and TV pressures are in-

creased or decreased by turning the

adjusting screw.

Before replacing or adjusting the di-

aphragm, it must first be determined

that the pressure or vacuum is actual-

ly out of specification and that the

cause of the problem is not due to

other items within the transmission or

vacuum connecting lines.

If the tests outlined in the Specifi-
cation Section have been performed

and pressures are within specification

but shift feel is unsatisfactory, or if

the pressure is too high or too low at

10 inches of vacuum, the vacuum di-

aphragm may be adjusted to improve

the shift feel.

If shifts are excessively harsh, the

diaphragm should be adjusted to re-

duce control pressure by backing off

the adjusting screw (counterclock-

wise).
If shift quality is extremely soft,

control pressure should be increased

by turning the adjusting screw inward

(clockwise).

To adjust the vacuum diaphragm to

compensate for harsh shift quality,

first check control pressure in D, 2

and 1 at 10 inches manifold vacuum

and note the pressure reading ob-

tained. Remove the T-fitting from the

vacuum hose and back off the adjust-

ing screw (counterclockwise) by one

full turn. Each full turn will reduce

control pressure by approximately 2

1/2 psi at 10 inches of vacuum. Test

the vehicle for shift feel. If shift quali-

ty is still harsh, a further adjustment

should be made to reduce control

pressure. However, control pressure

should not be reduced below the speci-

fication shown for 10 inches of vacu-

um. If control pressure has been re-

duced to the low limit and shift feel is

still excessively harsh, the clutches and

band should be checked for correct

operation.

To adjust the vacuum diaphragm to

compensate for extremely soft shifts,

record the control pressure reading at

10 inches of vacuum in D, 2 and 1,

then make an initial adjustment of

one full turn inward (clockwise). Test

the vehicle for shift feel and again ad-

just the diaphragm, if necessary. Con-

trol pressure at 10 inches of vacuum

must not exceed the high limit shown

in the Specification Section.

When the necessary adjustments

have been completed and shift feel is

satisfactory, repeat all the tests out-

ADJUSTING

SCREW

PRIMARY

THROTTLE VALVE
DIAPHRAGM

SPRING

D 1639-A

FIG. 15—Altitude Compensating Type Vacuum Diaphragm
lined in the Specification Section. All

tests must be within specifications.

The adjustable vacuum unit must not

be used to allow for adjusting control

or TV pressures that are out of speci-

fications. If these pressures are found

to be out of specifications the cause

must be determined and corrected bef-

ore making any adjustment.

NEUTRAL START SWITCH

ADJUSTMENT AND

REPLACEMENT—COLUMN SHIFT

There are two types of column-

mounted neutral start switches: A and

B.
Type A switch has a parking brake

brake-release vacuum valve. Type B

switches do not have a vacuum valve.

The switches differ in appearance but

not in operation. Both switches are

actuated by a removable steel lever,

which is installed in the shifter tube

within the steering column assembly.

The following procedures outline the

steps necessary to correctly adjust and

replace the neutral start switch.

SWITCH ADJUSTMENT

Neutral Position

1.
With the selector lever held light-

ly against the neutral stop, attempt to

start the engine. If the engine starts

while holding the lever but does not

start when the lever is released, the

shift linkage should be adjusted. If the

engine does not start in either condi-

tion, adjust the switch.

2.
To adjust the switch in neutral,

place the transmission selector lever

against the stop of the neutral detent

position.

3.
Loosen the two retaining screws

that locate the switch on the steering

column (Fig. 16).

4.
With the selector lever against

the neutral stop, rotate the switch

until a start in the neutral position is

obtained. Then, tighten the switch at-

taching screws to 20 in-lbs torque.

5.
With the switch properly adjust-

ed in neutral, place the selector lever

in the 1 position and push the park

reset button (Fig. 16) to the left

(counterclockwise) until it stops. The

park reset must be performed when-

ever the switch has been adjusted.

Park Position

1.
Place the selector lever in the

park position, release the lever and at-

tempt to start. If the engine does not

start, reset the park adjustment.procarmanuals.com

07-02-03

C4 Automatic Transmission

07-02-03

CONVERTER

FORWARD CLUTCH
PRIMARY GOVERNOR

CONVERTER

CHECK VALVE
ONE-WAY

CLUTCH

DRAIN-BACK

VALVE

FRONT LUBE

CONVERTER

PRESSURE

RELIEF VALVE
LOW AND

REVERSE

SERVO
AND DIRECT

CLUTCH

L

SECONDARY

GOVERNOR
INTERMEDIATE

BAND

ACCUMULATOR

VALVE
CUT-BACK
VALVE

2-3
BACK-OUT

VALVE

MAIN

REGU-

LATOR

VALVE
MANUAL
LOW

VALVE

1-2 SHIFT

VALVE

D2
VALVE
THROTTLE

MODULATOR

VALVE

THROTTLE

BOOST VALVE

PRESSURE

BOOSTER

VALVE

DOWNSHIFT VALVE

LINE

COASTING

BOOST

VALVE
ENGINE
MANIFOLD
VACUUM

LESS THAN
20
INCHES

PRIMARY

THROTTLE

VALVE

(CASE)
VACUUM

DIAPHRAGM

OIL
SCREEN

I) 1724-E

FIG. 3—Hydraulic Control Systemprocarmanuals.com