2002 CHRYSLER TOWN AND COUNTRY oil

(5) Place end cover onto P.T.U. case and install
bolts. Tighten bolts to 28 N´m (250 in. lbs.) in the
sequence shown in (Fig. 41). Retighten first bolt after
all others are tight.
CAUTION: When end cover is installed be careful
not to damage the P.T.U. Input Shaft Cover Seal.
(6) Reinstall P.T.U. assembly.
(7) Check and fill fluids as required.
INPUT SHAFT SEAL
REMOVAL
The Power Transfer Unit must be removed from
the vehicle to service this seal. Refer to Power Trans-
fer Unit Removal in this section for procedures.
(1) Remove P.T.U. end cover bolts (Fig. 42).
(2) Gently tap on end cover ears to separate cover
from case (Fig. 43).
(3) Remove ring gear oil trough (Fig. 44).
(4) Remove input shaft and ring gear from case
(Fig. 45).
(5) Use Special Tool No. 7794-A (seal puller) to
remove seal (Fig. 46).
Fig. 41 Bolt Tightening Sequence
Fig. 42 P.T.U. End Cover Bolts
1 - POWER TRANSFER UNIT
2 - FILL PLUG
3 - END COVER
4 - OUTPUT SHAFT
Fig. 43 End Cover Removal
1 - END COVER EARS
2 - HAMMER
3 - POWER TRANSFER UNIT
RSPOWER TRANSFER UNIT21-17
INPUT SHAFT END SEAL (Continued)
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INSTALLATION
The Power Transfer Unit must be removed from
the vehicle to service this seal. Refer to Power Trans-
fer Unit Removal in this section for procedures.
(1) Clean and inspect seal area.
(2) Lay housing on bench and install new seal with
seal driver C-4657 and handle C-4171 (Fig. 47). The
seal must be installed with the spring side facing
towards the ring gear. Drive the seal in until it bot-
toms against the case shoulder.
(3) Install input shaft.(4) Install oil trough.
Fig. 44 Oil Trough
1 - OIL TROUGH
2 - POWER TRANSFER UNIT
Fig. 45 Input Shaft and Ring Gear Removal
1 - POWER TRANSFER UNIT
2 - RING GEAR
Fig. 46 Seal Removal
1 - POWER TRANSFER UNIT
2 - SPECIAL TOOL 7794±A
Fig. 47 Seal Installation
1 - HAMMER
2 - SPECIAL TOOL C-4171
3 - SPECIAL TOOL C-4657
4 - POWER TRANSFER UNIT
21 - 18 POWER TRANSFER UNITRS
INPUT SHAFT SEAL (Continued)
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31TH AUTOMATIC TRANSAXLE
TABLE OF CONTENTS
page page
31TH AUTOMATIC TRANSAXLE
DESCRIPTION.........................22
OPERATION...........................24
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - PRELIMINARY
DIAGNOSIS..........................24
DIAGNOSIS AND TESTING - ROAD TEST . . . 31
DIAGNOSIS AND TESTING - HYDRAULIC
PRESSURE TESTS....................32
DIAGNOSIS AND TESTING - TORQUE
CONVERTER HOUSING FLUID LEAKAGE . . . 35
DIAGNOSIS AND TESTING - CLUTCH AND
SERVO AIR PRESSURE TESTS..........35
STANDARD PROCEDURE - ALUMINUM
THREAD REPAIR......................37
REMOVAL.............................37
DISASSEMBLY.........................40
ASSEMBLY............................51
INSTALLATION.........................61
SCHEMATICS AND DIAGRAMS
31TH TRANSAXLE HYDRAULIC
SCHEMATICS........................64
SPECIFICATIONS
31TH AUTOMATIC TRANSAXLE..........72
SPECIAL TOOLS
31TH AUTOMATIC TRANSAXLE..........75
ACCUMULATOR
DESCRIPTION.........................79
OPERATION...........................79
BANDS
DESCRIPTION
KICKDOWN (FRONT) BAND.............80
OPERATION
LOW/REVERSE (REAR) BAND...........80
ADJUSTMENTS
ADJUSTMENT - FRONT BAND...........80
ADJUSTMENTS - REAR BAND...........80
CLUTCH - FRONT
DESCRIPTION.........................82
OPERATION...........................82
DISASSEMBLY.........................82
ASSEMBLY............................84
CLUTCH - REAR
DESCRIPTION.........................86
OPERATION...........................86
DISASSEMBLY.........................87
ASSEMBLY............................89
FINAL DRIVE
DISASSEMBLY.........................91
ASSEMBLY............................94ADJUSTMENTS
ADJUSTMENT - DIFFERENTIAL BEARING . . 97
FLUID
STANDARD PROCEDURE
STANDARD PROCEDURE - FLUID LEVEL
AND CONDITION CHECK...............99
STANDARD PROCEDURE - FLUID AND
FILTER CHANGE......................99
GEAR SHIFT CABLE
REMOVAL............................101
INSTALLATION........................102
ADJUSTMENTS
GEARSHIFT CABLE ADJUSTMENT.......104
GOVERNOR
DESCRIPTION........................104
OPERATION..........................104
CLEANING...........................104
INSPECTION.........................104
OIL PUMP
DESCRIPTION........................105
OPERATION..........................105
STANDARD PROCEDURE - OIL PUMP
VOLUME CHECK.....................105
DISASSEMBLY........................106
CLEANING...........................106
INSPECTION.........................106
ASSEMBLY...........................107
PARK/NEUTRAL POSITION SWITCH
DIAGNOSIS AND TESTING - PARK/NEUTRAL
POSITION SWITCH...................107
REMOVAL............................107
INSTALLATION........................107
PLANETARY GEARTRAIN
DISASSEMBLY........................108
ASSEMBLY...........................109
SEAL - OIL PUMP
REMOVAL............................110
INSTALLATION........................110
SERVO - KICKDOWN
DESCRIPTION........................111
OPERATION..........................111
DISASSEMBLY........................111
CLEANING...........................112
INSPECTION..........................113
ASSEMBLY...........................113
SERVO - LOW/REVERSE
DESCRIPTION........................113
OPERATION..........................113
DISASSEMBLY........................114
CLEANING...........................114
RS31TH AUTOMATIC TRANSAXLE21-21
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ASSEMBLY...........................115
SHIFT INTERLOCK SOLENOID
DESCRIPTION........................115
OPERATION..........................115
DIAGNOSIS AND TESTING - BRAKE/
TRANSMISSION SHIFT INTERLOCK
SOLENOID..........................117
REMOVAL............................117
INSTALLATION........................118
SOLENOID - TCC
DESCRIPTION........................119
OPERATION..........................119
REMOVAL............................119
INSTALLATION........................120
THROTTLE VALVE CABLE
REMOVAL............................120
INSTALLATION........................121
ADJUSTMENTS
THROTTLE VALVE LINKAGE
ADJUSTMENT.......................122
TORQUE CONVERTER
DESCRIPTION........................122
OPERATION..........................126
REMOVAL............................127
INSTALLATION........................127
TRANSFER SYSTEM - OUTPUT SHAFT/GEAR/
BEARING
REMOVAL............................128INSTALLATION........................131
ADJUSTMENTS
ADJUSTMENT - OUTPUT SHAFT BEARING . 135
TRANSFER SYSTEM - TRANSFER SHAFT/
GEAR/BEARING
REMOVAL............................137
INSTALLATION........................141
ADJUSTMENTS
ADJUSTMENT - TRANSFER SHAFT
BEARING...........................145
VALVE BODY
REMOVAL............................146
DISASSEMBLY........................148
CLEANING...........................154
INSPECTION.........................155
ASSEMBLY...........................155
INSTALLATION........................158
ADJUSTMENTS
HYDRAULIC CONTROL PRESSURE
ADJUSTMENTS......................160
VEHICLE SPEED SENSOR/PINION GEAR
REMOVAL............................160
INSTALLATION........................160
31TH AUTOMATIC
TRANSAXLE
DESCRIPTION
This transaxle combines torque converter, three
speed transmission, final drive gearing, and differen-
tial into a front wheel drive system.
Within this transaxle, there are three primary
areas:
(1) Main center line plus valve body.
(2) Transfer shaft center line (includes governor
and parking sprag).
(3) Differential center line.
Center distances between the main rotating parts
in these three areas are held precise to maintain a
low noise level.
The torque converter, transaxle area, and differen-
tial are housed in an integral aluminum die casting.
The differential oil sump is common with the
transaxle sump. Separate filling of the differen-
tial is NOT necessary.
The torque converter is attached to the crankshaft
through a flexible driving plate. Cooling of the con-
verter is accomplished by circulating the transaxle
fluid through a remote cooler. There are two types of
coolers used. An oil-to-water type cooler located in
the radiator side tank and/or an oil-to-air heatexchanger. The torque converter assembly is a sealed
unit that cannot be disassembled.
The transaxle fluid is filtered by an internal filter
attached to the lower side of the valve body assembly.
Engine torque is transmitted to the torque con-
verter and then through the input shaft to multiple-
disc clutches in the transaxle. The power flow
depends on the application of the clutches and bands.
Refer to Elements in Use Chart in Diagnosis and
Tests section.
The transaxle consists of:
²Two multiple-disc clutches
²An overrunning clutch
²Two servos
²A hydraulic accumulator
²Two bands
²Two planetary gear sets
This provides three forward ratios and a reverse
ratio. The common sun gear of the planetary gear
sets is connected to the front clutch by a driving
shell. The driving shell is splined to the sun gear and
front clutch retainer. The hydraulic system consists
of an oil pump and a single valve body which con-
tains all of the valves except the governor valves.
The transaxle sump and differential sump are both
vented through the dipstick. Output torque from the
main center line is delivered through helical gears to
the transfer shaft. This gear set is a factor in the
transaxle final drive (axle) ratio. The shaft also car-
21 - 22 31TH AUTOMATIC TRANSAXLERS
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31TH Automatic Transaxle
1 - TORQUE CONVERTER CLUTCH
2 - TORQUE CONVERTER
3 - OIL PUMP
4 - FRONT CLUTCH
5 - REAR CLUTCH
6 - OVER-RUNNING CLUTCH7 - PLANETARY GEARS
8 - TRANSFER GEARS
9 - SHAFT
10 - GOVERNOR
11 - DIFFERENTIAL
RS31TH AUTOMATIC TRANSAXLE21-23
31TH AUTOMATIC TRANSAXLE (Continued)
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TRANSAXLE DIAGNOSIS CHARTS
CONDITION POSSIBLE CAUSES CORRECTION
HARSH ENGAGEMENT
(FROM NEUTRAL TO
DRIVE OR REVERSE)1. Fluid Level Low 1. Add Fluid
2. Throttle Linkage Misadjusted 2. Adjust linkage - setting may be too long.
3. Excessive Pinion Backlash 3. Check per Service Manual. Correct as
needed.
4. Hydraulic Pressure Incorrect 4. Check pressure. Remove, overhaul or
adjust valve body as needed.
5. Band Misadjusted. 5. Adjust rear band.
6. Valve Body Check Balls Missing. 6. Inspect valve body for proper check ball
installation.
7. Clutch, band or planetary
component Damaged.7. Remove, disassemble and repair
transmission as necessary.
8. Converter Clutch (if equipped)
Faulty.8. Replace converter and flush cooler and
line before installing new converter.
DELAYED ENGAGEMENT
(FROM NEUTRAL TO
DRIVE OR REVERSE)1. Fluid Level Low. 1. Correct level and check for leaks.
2. Filter Clogged. 2. Change filter.
3. Gearshift Linkage Misadjusted. 3. Adjust linkage and repair linkage if worn
or damaged.
4. Rear Band Misadjusted. 4. Adjust band.
5. Valve Body Filter Plugged. 5. Replace fluid and filter. If oil pan and old
fluid were full of clutch disc material and/or
metal particles, overhaul will be necessary.
6. Oil Pump Gears Worn/Damaged. 6. Remove transmission and replace oil
pump.
7. Hydraulic Pressure Incorrect. 7. Perform pressure test, remove
transmission and repair as needed.
8. Reaction Shaft Seal Rings
Worn/Broken.8. Remove transmission, remove oil pump
and replace seal rings.
9. Rear Clutch/Input Shaft, Rear
Clutch Seal Rings Damaged.9. Remove and disassemble transmission
and repair as necessary.
10. Governor Valve Stuck. 10. Remove and inspect governor
components. Replace worn or damaged
parts.
11. Regulator Valve Stuck. 11. Clean.
RS31TH AUTOMATIC TRANSAXLE21-25
31TH AUTOMATIC TRANSAXLE (Continued)
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CONDITION POSSIBLE CAUSES CORRECTION
NO DRIVE RANGE
(REVERSE OK)1. Fluid Level Low. 1. Add fluid and check for leaks if drive is
restored.
2. Gearshift Linkage/Cable
Loose/Misadjusted.2. Repair or replace linkage components.
3. Rear Clutch Burnt. 3. Remove and disassemble transmission
and rear clutch and seals. Repair/replace
worn or damaged parts as needed.
4. Valve Body Malfunction. 4. Remove and disassemble valve body.
Replace assembly if any valves or bores
are damaged.
5. Transmission Overrunning Clutch
Broken.5. Remove and disassemble transmission.
Replace overrunning clutch.
6. Input Shaft Seal Rings Worn/
Damaged.6. Remove and disassemble transmission.
Replace seal rings and any other worn or
damaged parts.
7. Front Planetary Failed Broken. 7. Remove and repair.
NO DRIVE OR REVERSE
(VEHICLE WILL NOT
MOVE)1. Fluid Level Low. 1. Add fluid and check for leaks if drive is
restored.
2. Gearshift Linkage/Cable
Loose/Misadjusted.2. Inspect, adjust and reassemble linkage
as needed. Replace worn/damaged parts.
3. Filter Plugged. 3. Remove and disassemble transmission.
Repair or replace failed components as
needed. Replace filter. If filter and fluid
contained clutch material or metal particles,
an overhaul may be necessary. Perform
lube flow test. Flush oil. Replace cooler as
necessary.
4. Oil Pump Damaged. 4. Perform pressure test to confirm low
pressure. Replace pump body assembly if
necessary.
5. Valve Body Malfunctioned. 5. Check press and inspect valve body.
Replace valve body (as assembly) if any
valve or bore is damaged. Clean and
reassemble correctly if all parts are in good
condition.
6. Transmission Internal Component
Damaged.6. Remove and disassemble transmission.
Repair or replace failed components as
needed. Remove and disassemble
transmission. Repair or replace failed
components as needed.
7. Park Sprag not Releasing - Check
Stall Speed, Worn/Damaged/Stuck.7. Remove, disassemble, repair.
8. Torque Converter Damage. 8. Inspect and replace as required.
21 - 26 31TH AUTOMATIC TRANSAXLERS
31TH AUTOMATIC TRANSAXLE (Continued)
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CONDITION POSSIBLE CAUSES CORRECTION
BUZZING NOISE 1. Fluid Level Low 1. Add fluid and check for leaks.
2. Shift Cable Misassembled. 2. Route cable away from engine and bell
housing.
3. Valve Body Misassembled. 3. Remove, disassemble, inspect valve
body. Reassemble correctly if necessary.
Replace assembly if valves or springs are
damaged. Check for loose bolts or screws.
4. Pump Passages Leaking 4. Check pump for porous casting, scores
on mating surfaces and excess rotor
clearance. Repair as required. Loose pump
bolts.
5. Cooling System Cooler Plugged. 5. Flow check cooler circuit. Repair as
needed.
6.Overrunning Clutch Damaged. 6. Replace clutch.
SLIPS IN REVERSE ONLY 1. Fluid Level Low. 1. Add fluid and check for leaks.
2. Gearshift Linkage Misadjusted. 2. Adjust linkage.
3. Rear Band Misadjusted. 3. Adjust band.
4. Rear Band Worn. 4. Replace as required.
5. Hydraulic Pressure Too Low. 5. Perform hydraulic pressure tests to
determine cause.
6. Rear Servo Leaking. 6. Air pressure check clutch-servo operation
and repair as required.
7. Band Linkage Binding. 7. Inspect and repair as required.
SLIPS IN FORWARD
DRIVE RANGES1. Fluid Level Low. 1. Add fluid and check for leaks.
2. Fluid Foaming. 2. Check for high oil level, bad pump
gasket or seals, dirt between pump halves
and loose pump bolts. Replace pump if
necessary.
3. Throttle Linkage Misadjusted. 3. Adjust linkage.
4. Gearshift Linkage Misadjusted. 4. Adjust linkage.
5. Rear Clutch Worn. 5. Inspect and replace as needed.
6. Low Hydraulic Pressure Due to
Worn Pump, Incorrect Control
Pressure Adjustments, Valve Body
Warpage or Malfunction, Sticking
Governor, Leaking Seal Rings,
Clutch Seals Leaking, Servo Leaks,
Clogged Filter or Cooler Lines6. Perform hydraulic and air pressure tests
to determine cause.
7. Rear Clutch Malfunction, Leaking
Seals or Worn Plates.7. Air pressure check clutch-servo operation
and repair as required.
8. Overrunning Clutch Worn, Not
Holding (Slips in 1 Only).8. Replace Clutch.
SLIPS IN LOW GEAR9D9
ONLY, BUT NOT IN 1
POSITIONOverrunning Clutch Faulty. Replace overrunning clutch.
RS31TH AUTOMATIC TRANSAXLE21-29
31TH AUTOMATIC TRANSAXLE (Continued)
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