1990 MITSUBISHI ECLIPSE Service Manual

-.AUTOMATIC TRANSAXLE
- Transaxle Mechanism21-25
-FRONT CLUTCH
Clutch plate,
Check valve
Piston -Front clutch retainer
-
D-nng
XHydraulicpressure
-Snap ring
.
‘Snap ring(Selection)1750213Front
ClUtCh IS ot tne multtple alsc n/pe, ana IScomposed of a front clutch retainer, discs, plates,
and a piston. The front clutch is actuated when the‘3 is in forward third or back gear. It conveys
&..rving force of the input shaft to the reverse sun
gear.1 I.D.mm (in.)I66 (2.60)I
POWER FLOW
Rear clutch retainerFront clutch,
\
Klckdown drumReverse sun gear/
IInput shaftRear clutch retainerReverse sun gear

21-26AUTOMATIC TRANSAXLE - Transaxle Mechanism
REAR CLUTCH
Wave sprmgRear clutch retainer
Clutch reaction piateClutch pressure plate
I1rao2l5Rear clutch is of the multiple disc type, and is
composed of a rear clutch retainer, disc, plates, and
a piston. When the piston is actuated by the oil
pressure, the multiple disc clutch is connected,
conveying driving force from the input shaft to the
forward sun gear in the planetary gear set. The rear
clutch is always actuated when the shift is in first,
second and third gears.
INumber of clutch discsI.3I
1 Number of clutch piates1 2 I-
I Number of reaction plates
I
1 1
I Number of pressure plates’I 1 I
PistonO.D.mm (in.)121 (4.761
I.D.mm (in.)36 (1.42)
POWER FLOW
Rear clutch
Rear clutch hubRear clutch retainer
Forward sun gear,
IInput shaftRear clutch retainerRear clutchRear clutch hubForward sun gear

AUTOMATIC TRANSAXLE - Transaxle Mechanism21-27
/clutch plate-Piston
End clutchretainer
(“7Hydraulic
pressure
POWER FLOWEND CLUTCH
End clutch is of the multiple disc type and is installed at the rear
end of the input shaft. The clutch is actuated in the fourth gear
(overdrive) to transmit the power from the input shaft to the
planetary gear carrier.
Actually. the end clutch also operates during third gear, and thisis to maintain smooth up-shifting to fourth gear.
Number of clutch discs3Number of clutch plates
3Number of reaction plates
1
PistonO.D.mm (in.)124 (4.88)I
I.D.mm (in.)29 (1.14)J
End clutchEnd clutch
IInput shaftEnd clutch retainerEnd clutch shaft
Carrier
a

.-
I
21-28AUTOMATIC TRANSAXLE - Transaxle Mechanism
KICKDOWN BRAKE
/Kickdown band
r\\ IKickdown sleeve
- Kickdown servo
switch
;‘- Locknut
Apply pressure
(2nd pressure)
1 Release pre&re (3rd pressure)I,
/ --Anchor
1750219The kickdown brake is a band type brake; it is
piston and rod moves toward the left, tightening the
composed of a kickdown band, drum, kickdownbrake band to hold the kickdown drum. As a result,
servo, switch and anchor.the reverse sun gear (interlocked with the kickdown
When the
2nd pressure is admitted to the apply sidedrum) is held. This brake functions during 2nd gear
chamber of,kickdown servo cylinder, the kickdownand during overdrive.

ToThe kickdown servo switch detects the position of thekickdown piston just before the brake is applied, and sends the
signal to the transaxle control unit. Using this signal, the
transaxle control unit controls the 2nd pressure both before,
and
during application of the brake. In the initial control stage or
until just before the kickdown brake
is applied, a higher 2ndpressure is supplied to the kickdown servo SO that thekickdown piston can move quickly for
faSter response to thekickdown condition that has been initiated. In the second
control
stage or while the brake is being applied, the 2nd
1750394pressure
is regulated at an optimum level SO that the band is
tightened on the drum the proper amount
for good kickdown
“feeling.”AUTOMATIC TRANSAXLE
- Transaxle MechanismY$21-29
,
ilOLDING DRUM WITH KICKDOWN BRAKE

21-30AUTOMATIC TRANSAXLE - Transaxle Mechanism
LOW-REVERSE. BRAKECentersupport
Hydraulic pressure.
Piston1750221
Low-Reverse brake is of the multiple disc type and
is composed of a center support, disc, plates, and a
piston. The brake operates when the shift is in
1stgear in the “L” range or back gear. It fastens the
carrier in the planetary gear set. That is, the shafts ofthe long and short pinions are fastened.
HOLDING CARRIER WITH LOW-REVERSE BRAKE
rLow-Reverse brake
Low-Reverse brake

iAUTOMATIC TRANSAXLE
- Transaxle Mechanism
ONE-WAY CLUTCH
I
’
21-31
Long pinion(Planetary gear carrier)
CarrierInput
output
Held
stationary
sun gear
170207170320One-way clutch is of the sprag type and is
incorpo-rated between the pinion carrier and the center
support.
In
1st gear (D or 2 range), the long pinion rotates
clockwise as viewed in’the direction of arrow P. This
produces a force which has the tendency to cause
the carrier to rotate counterclockwise, but the
carrier is blocked from rotating in that direction by
the one-way clutch. As a result. the long pinion
transmits its force to the
annulus gear.
The carrier, which is coupled with the one-wayclutch outer race, is free to turn in clockwise
direction. In an engine braking condition under
which the
annulus gear is turned first. the carrier
turns clockwise freely and, therefore, the engine
braking effect is not obtained.
INumber of sprags26
Width of clutchmm (in.)18.3 (720)HOLDING CARRIER WITH ONE-WAY CLUTCH
P 0
On-y clutchI
\Carrierl7so223

21-32AUTOMATIC TRANSAXLE - Transaxle Mechanism
PLANETARY GEAR
-.., ‘~ ~,.~.“.,
Reverse sun gear\ParkIng sprag
Carrier\
I\
i
\
Outer race.-End clutch shaftLow/reverse brake’s hub
Short pmlon17502L
The planetary gear set incorporated in
thus transaxle
is of the Ravigne’aux-type, and consists of a forward
sun gear, a reverse sun gear, a short prnion. a long
pinion, a carrier to support both pinions, and an
annulus gear.
The reverse sun gear is connected to the front
clutch retainer via the
kickdown drum, while the
forward sun gear is connected to the rear
clutchhub.
The carrier is built in one unit with the low reverse
brake’s hub and the outer race of the one-way
clutch. The carrier is connected to the end clutch via
the end clutch shaft.
The
annulus gear, to which the output flange isconnected, conveys driving force to the transfer
drive gear installed on the output flange. And the
parking sprag is provided on the outer circumfer-
ence of the
annulus gear.
Number of forward sun gear teeth
Number of reverse sun gear teeth
2634
INumber of short pinron teethI22 1Number of long pinion -teeth
Number of
annulus gear teeth74 1c-’