Mitsubishi Galant. Manual — part 384

GENERAL DESCRIPTION

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AUTOMATIC TRANSAXLE

23A-3

.

G EN ER A L DESC RIPTIO N

M1231000100065

The A/T come in two models, namely, F4A42 and
F4A51.

TRANSAXLE

The transaxle is configured of the torque converter and gear train. A 3-element, 1-step, 2-phase torque
converter with built-in torque converter clutch is incorporated. The gear train is configured of three sets of
multi-plate clutches, two sets of multi-plate brakes, one set of one-way clutches and two sets of planetary
gears configured of the sun gears, carriers, pinion gears and annulus gears.

ITEMS

SPECIFICATIONS

Transaxle model

F4A42

F4A51

Engine model

4G64 (2.4L Engine)

6G72 (3.0L Engine)

Torque converter

Type

3-element, 1-stage, 2-phase

Torque converter clutch

Provided (3rd to 4th)

Stall torque ratio

1.9

2.0

Transaxle type

4-speed forward, 1-speed reverse fully automatic

Gear ratio

1st

2.842

2.842

2nd

1.529

1.495

3rd

1.000

1.000

4th

0.712

0.731

Reverse

2.480

2.720

Final gear ratio (Differential gear ratio)

4.042

3.735

Number of underdrive clutch discs

4

Number of overdrive clutch discs

4

Number of reverse clutch discs

2

Number of low-reverse brake discs

6

Number of second brake discs

3

4

Manual control type

P-R-N-D-3-2-L (7 positions)

Shift pattern control

Electronic control (INVECS-II)

Oil pressure control during shifting

Electronic control
(each oil pressure independently controlled)

Torque converter clutch control

Electronic control

Speedometer gear ratio

29/36

GENERAL DESCRIPTION

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AUTOMATIC TRANSAXLE

23A-4

TRANSAXLE CONFIGURATION DRAWING

COMPONENTS AND FUNCTIONS

FUNCTION ELEMENT TABLE

AC001813

OD

REV

2ND LR

OWC

UD

AB

COMPONENT

FUNCTION

Underdrive clutch

UD

connects the input shaft to the underdrive sun gear.

Reverse clutch

REVconnects the input shaft to the reverse sun gear.

Overdrive clutch

OD

connects the input shaft to the overdrive planetary carrier.

Low-reverse brake

LR

holds the low-reverse annulus gear and the overdrive planetary
carrier.

Second brake

2ND

holds the reverse sun gear.

One-way clutch

OWC

restricts the rotation direction of the low-reverse annulus gear.

OPERATING
ELEMENT

ENGINE
START

PARKING
MECHANI
SM

UNDERD
RIVE
CLUTCH
(UD)

REVERSE
CLUTCH
(REV)

OVER-
DRIVE
CLUTCH
(OD)

LOW-
REVERSE
BRAKE
(LR)

SECOND
BRAKE
(2ND)

SELECTOR LEVER
POSITION

P

Parking

OK

×

−

−

−

×

−

R

Reverse

−

−

−

×

−

×

−

N

Neutral

OK

−

−

−

−

×

−

D

1st

−

−

×

−

−

×

*

−

2nd

−

−

×

−

−

−

×

3rd

−

−

×

−

×

−

−

4th

−

−

−

−

×

−

×

3

1st

−

−

×

−

−

×

*

−

2nd

−

−

×

−

−

−

×

3rd

−

−

×

−

×

−

−

GENERAL DESCRIPTION

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AUTOMATIC TRANSAXLE

23A-5

×

: Function element

NOTE: * operates only when the vehicle is stationary [at approximately 10 km/h (6.2 mph) or less].

2

1st

−

−

×

−

−

×

*

−

2nd

−

−

×

−

−

−

×

L

1st

−

−

×

−

−

×

−

OPERATING
ELEMENT

ENGINE
START

PARKING
MECHANI
SM

UNDERD
RIVE
CLUTCH
(UD)

REVERSE
CLUTCH
(REV)

OVER-
DRIVE
CLUTCH
(OD)

LOW-
REVERSE
BRAKE
(LR)

SECOND
BRAKE
(2ND)

SELECTOR LEVER
POSITION

GENERAL DESCRIPTION

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AUTOMATIC TRANSAXLE

23A-6

SECTIONAL VIEW <F4A42>

AC001814

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

AB

1. REVERSE CLUTCH

2. OVERDRIVE PLANETARY CARRIER

3. SECOND BRAKE

4. LOW-REVERSE BRAKE

5. OUTPUT PLANETARY CARRIER

6. ONE-WAY CLUTCH

7. TRANSFER DRIVE GEAR

8. TRANSAXLE CASE

9. UNDERDRIVE CLUTCH

10. TORQUE CONVERTER

11. TORQUE CONVERTER CLUTCH

12. INPUT SHAFT

13. OIL PUMP

14. TORQUE CONVERTER HOUSING

15. DIFFERENTIAL

16. TRANSFER DRIVEN GEAR
17. OUTPUT SHAFT
18. REAR COVER
19. OVERDRIVE CLUTCH