Page 937 of 1771

Description
(cont'd)
Gear Selectio n
The shif t leve r ha s seve n positions : PARK , REVERSE, NEUTRAL , 1st throug h 4t h gea r ranges , 1s t throug h
3rd gea r ranges , 2n d gea r an d 1s t gear .
Positio nDescriptio n
PARK
REVERS E
NEUTRAL
] DRIV E
(1st throug h 4th )
DRIV E
(1st throug h 3rd )
SECON D
FIRST
Front wheel s locked ; parkin g paw l engage d wit h parkin g gea r o n countershaft . Al l clutche s released .
Reverse ; revers e selecto r engage d wit h countershaf t revers e gea r an d 4t h clutc h locked .
Al l clutche s released .
Genera l driving ; start s of f i n 1st , shift s automaticall y t o 2nd , 3rd , the n 4th , dependin g o n vehicl e
spee d an d throttl e position . Downshif t throug h 3rd , 2n d an d 1s t o n deceleratio n t o stop . Th e lock-u p
mechanis m come s int o operatio n i n positio n i n 2nd , 3r d an d 4t h gear .
Fo r rapi d acceleratio n a t highwa y speed s an d genera l driving ; up-hil l an d down-hil l driving ; start s of f
i n 1st , shift s automaticall y t o 2nd , the n 3rd , dependin g o n vehicl e spee d an d throttl e position .
Downshift s throug h 2n d t o 1s t o n deceleratio n t o stop . Th e lock-u p mechanis m come s int o operatio n
i n 3r d speed .
Fo r engin e brakin g o r bette r tractio n startin g of f o n loos e o r slipper y surfaces ; stay s i n 2n d gear ,
doe s no t shif t u p o r down .
Fo r engin e braking ; stay s i n 1s t gear , doe s no t shif t up .
Startin g i s possibl e onl y i n an d position s throug h th e us e o f a slide-type , neutral-safet y switch .
Automati c Transaxl e (A/T ) Gea r Positio n Indicato r
Th e A/ T gea r positio n indicato r i n th e instrumen t pane l show s whic h gea r ha s bee n selecte d withou t havin g t o loo k dow n
a t th e console .
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Page 938 of 1771
RING GEAR
EXTENSION
SHAFT
TORQUE
CONVERTER
2ND CLUTCH
4TH CLUTCH
1ST CLUTCH
SECONDARY
DRIVEN GEAR
A/T GEAR
POSITION SWITCH
1ST-HOLD
CLUTCH
COUNTERSHAFT
SPEED SENSOR
3RD
CLUTCHProCarManuals.com
Page 939 of 1771

Description
Clutches
The four-spee d automati c transmissio n use s hydraulically-actuate d clutche s t o engag e o r disengag e th e transmissio n gears .
Whe n hydrauli c pressur e i s introduce d int o th e clutc h drum , th e clutc h pisto n moves . Thi s presse s th e frictio n disc s an d
stee l plate s together , lockin g the m s o the y don' t slip . Powe r i s the n transmitte d throug h th e engage d clutc h pac k t o it s
hub-mounte d gear .
Likewise , whe n th e hydrauli c pressur e is ble d fro m th e clutc h pack , th e pisto n release s th e frictio n disc s an d th e stee l plates ,
an d the y ar e fre e t o slid e pas t each . Thi s allow s th e gea r t o spi n independentl y o n it s shaft , transmittin g n o power .
1s t Clutc h
Th e 1s t clutc h engages/disengage s 1s t gear , an d is locate d a t th e en d o f th e mainshaft , jus t behin d th e rea r cover .
Th e 1s t clutc h i s supplie d hydrauli c pressur e b y it s AT F fee d pip e withi n th e mainshaft .
1st-hol d Clutc h
The 1st-hol d clutc h engages/disengages 1st-hold o r position , an d i s locate d a t th e en d o f th e countershaft , jus t behin d
th e rea r cover . Th e 1st-hol d clutc h is supplie d hydrauli c pressur e b y it s AT F fee d pip e withi n th e countershaft .
2n d Clutc h
Th e 2n d clutc h engages/disengage s 2n d gear , an d i s locate d a t th e cente r o f th e mainshaft . Th e 2n d clutc h i s joine d back -
to-bac k t o th e 4t h clutch . Th e 2n d clutc h i s supplie d hydrauli c pressur e throug h th e mainshaf t b y a circui t connecte d t o th e
interna l hydrauli c circuit .
3r d Clutc h
Th e 3r d clutc h engages/disengage s 3r d gear , an d i s locate d a t th e en d o f th e countershaft .
Th e 3r d clutc h i s supplie d hydrauli c pressur e b y it s AT F fee d pip e withi n th e countershaft .
4t h Clutc h
Th e 4t h clutc h engages/disengage s 4t h gear , a s wel l a s revers e gear , an d i s locate d a t th e cente r o f th e mainshaft . Th e 4t h
clutc h i s joine d back-to-bac k t o th e 2n d clutch . Th e 4t h clutc h i s supplie d hydrauli c pressur e b y it s AT F fee d pip e withi n th e
mainshaft .
One-wa y Clutc h
Th e one-wa y clutc h i s positione d betwee n th e countershaf t 1s t gea r an d th e parkin g gear , wit h th e parkin g gea r spline d t o th e
countershaft . Th e 1s t gea r provide s th e oute r rac e surface , an d th e parkin g gea r provide s th e inne r rac e surface . Th e one -
wa y clutc h lock s u p whe n powe r i s transmitte d fro m th e mainshaf t 1s t gea r t o th e countershaf t 1s t gear .
The 1s t clutc h an d gear s remai n engage d in th e 1st , 2nd , 3rd , an d 4t h gea r range s i n th e o r position .
However, th e one-wa y clutc h disengage s whe n th e 2nd , 3rd , o r 4t h clutches/gear s ar e applie d in th e o r position .
Thi s i s becaus e th e increase d rotational speed o f th e gear s o n th e countershaf t override s th e lockin g "spee d range " o f th e
one-wa y clutch . Thereafter , th e one-wa y clutc h free-wheel s wit h th e 1s t clutc h stil l engaged .
COUNTERSHAF T 1S T GEA R
LOCK S
SPRA G
LOCKSFREE
PARKIN G GEA RNOTE : Vie w fro m rea r cove r side .
ProCarManuals.com
Page 940 of 1771
FRONT
EXTENSION
SHAFT
SECONDARY
DRIVE GEAR
SECONDARY
DRIVEN GEAR
3RD CLUTCH
COUNTERSHAFT
3RD GEAR
DRIVE PLATE/RING GEAR
TORQUE CONVERTER
COUNTERSHAFT
SPEED SENSOR
COUNTERSHAFT 2ND GEAR
COUNTERSHAFT 4TH GEAR
REVERSE SELECTOR
COUNTERSHAFT
REVERSE GEAR
PARKING GEAR
COUNTERSHAFT 1ST GEAR
ONE-WAY CLUTCH
1ST-HOLD CLUTCH
MAINSHAFT SPEED SENSOR
MAINSHAFT 3RD GEAR
MAINSHAFT 2ND GEAR
2ND CLUTCH
4TH CLUTCH
MAINSHAFT 4TH GEAR
MAINSHAFT REVERSE GEAR
MAINSHAFT 1ST GEAR
1ST CLUTCH
MAINSHAFT
COUNTERSHAFT
ATF PUMP GEARSProCarManuals.com
Page 941 of 1771
Description
Power FlowProCarManuals.com
Page 942 of 1771
Position
Hydraulic pressure is not applied to the clutches. Power is not transmitted to the countershaft.
Position
Hydraulic pressure is not applied to the clutches. Power is not transmitted to the countershaft. The countershaft is locked
by the parking brake pawl interlocking the parking gear.
TORQUE
CONVERTER
SECONDARY
DRIVE
GEAR
2ND CLUTCH
4TH CLUTCH
1ST CLUTCH
MAINSHAFT
COUNTERSHAFT
1ST-HOLD
CLUTCH
ONE-WAY CLUTCH
SERVO VALVE
(SHIFT FORK SHAFT)
3RD CLUTCH
SECONDARY DRIVEN
GEARProCarManuals.com
Page 943 of 1771
Description
Power Flow (cont'd)
Position
In position, hydraulic pressure is applied to the 1st clutch and the 1st-hold clutch.
The power flow when accelerating is as follows:
1. The hydraulic pressure is applied to the 1st clutch on the mainshaft, and power is transmitted via the 1st clutch to the
mainshaft 1st gear.
2. Hydraulic pressure is also applied to the 1st-hold clutch on the countershaft. Power transmitted to the mainshaft 1st
gear is conveyed via the countershaft 1st gear to the one-way clutch and the 1st-hold clutch. The one-way clutch is
used to drive the countershaft, and the 1st-hold clutch drives the countershaft.
3. Power is transmitted to the secondary drive gear, which drives the secondary driven gear.
TORQUE CONVERTER
MAINSHAFT
1ST GEAR
SECONDARY
DRIVE GEAR
1ST CLUTCH
MAINSHAFT
COUNTERSHAFT
1ST-HOLD
CLUTCH
COUNTERSHAFT
1ST GEAR
ONE-WAY CLUTCH
SECONDARY DRIVEN GEAR
PARKING GEARProCarManuals.com
Page 944 of 1771
Position
The power flow when decelerating is as follows:
1. Rolling resistance from the road surface goes through the front wheels to the secondary drive gear, then to the coun-
tershaft 1st gear via the 1st-hold clutch which is applied during deceleration.
2. The one-way clutch disengages at this time because the application of torque is reversed.
3. The counterforce conveyed to the countershaft 1st gear turns the mainshaft 1st gear. At this time, since hydraulic
pressure is also applied to the 1st clutch, counterforce is also transmitted to the mainshaft. As a result, engine braking
can be obtained with 1st gear.
TORQUE CONVERTER
MAINSHAFT 1ST GEAR
1ST CLUTCH
MAINSHAFT
SECONDARY
DRIVE GEAR
COUNTERSHAFT
1ST-HOLD
CLUTCH
COUNTERSHAFT
1ST GEAR
SECONDARY DRIVEN GEARProCarManuals.com