2002 CHRYSLER CARAVAN check oil

(4) Remove bearing retaining snap ring (Fig. 18).
(5) Use bearing puller MD998346 to remove bear-
ing (Fig. 19).
INSTALLATION
The end cover ball bearing can be removed and
installed without removing the Power Transfer Unit
from the vehicle. When replacing the bearing the output
seal must be removed to gain access to the bearing.
CAUTION: When installing bearing, position the
bearing in place by hand square to the bore. Other-
wise, bearing and/or housing damage may occur
upon installation.(1) Use installer MD998200 and driver handle
C-4171 to install bearing (Fig. 20) into the housing.
(2) Install bearing retaining snap ring.
CAUTION: When installing bearing retaining snap
ring, be sure to index the snap ring so that the
snap ring does not cover bearing oil passage.
(3) Install new outer half shaft seal using
MD998334 seal installer (Fig. 21).Do not reuse the
old seal.
(4) Reinstall right front half shaft.
(5) Check and fill fluids as required.
Fig. 18 Bearing Snap Ring
1 - BEARING
2 - SNAP RING PLIERS
3 - BEARING SNAP RING
Fig. 19 Bearing Removal
1 - P.T.U. END COVER
2 - SPECIAL TOOL MD998346
Fig. 20 Bearing Installation
1 - SPECIAL TOOL MD998200
2 - SPECIAL C-4171
Fig. 21 Installing New Seal
1 - P.T.U. END COVER
2 - HAMMER
3 - SPECIAL TOOL MD998334
21 - 10 POWER TRANSFER UNITRS
END COVER BALL BEARING (Continued)
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(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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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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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)
ProCarManuals.com

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)
ProCarManuals.com

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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CONDITION POSSIBLE CAUSES CORRECTION
GROWLING, GRATING OR
SCRAPING NOISES1. Drive Plate Broken. 1. Replace.
2. Torque Converter Bolts Hitting
Dust Shield.2. Dust shield bent. Replace or repair.
3. Planetary Gear Set Broken/
Seized.3. Check for debris in oil pan and repair as
required.
4. Overrunning Clutch Worn/Broken. 4. Inspect and check for debris in oil pan.
Repair as required.
5. Oil Pump Components Scored/
Binding.5. Remove, inspect and repair as required.
6. Output Shaft Bearing or Bushing
Damaged.6. Remove, inspect and repair as required.
7. Clutch Operation Faulty. 7. Perform air pressure check and repair as
required.
8. Front and Rear Bands
Misadjusted.8. Adjust bands.
DRAGS OR LOCKS UP 1. Fluid Level Low. 1. Check and adjust level.
2. Clutch Dragging/Failed 2. Air pressure check clutch operation and
repair as required.
3. Front or Rear Band Misadjusted. 3. Adjust bands.
4. Case Leaks Internally. 4. Check for leakage between passages in
case.
5. Servo Band or Linkage
Malfunction.5. Air pressure check servo operation and
repair as required.
6. Overrunning Clutch Worn. 6. Remove and inspect clutch. Repair as
required.
7. Planetary Gears Broken. 7. Remove, inspect and repair as required
(look for debris in oil pan).
WHINE/NOISE RELATED
TO ENGINE SPEED1. Fluid Level Low. 1. Add fluid and check for leaks.
2. Shift Cable Incorrect Routing. 2. Check shift cable for correct routing.
Should not touch engine or bell housing.
TORQUE CONVERTER
LOCKS UP IN SECOND
AND/OR THIRD GEARLockup Solenoid, Relay or Wiring
Shorted/Open.Test solenoid, relay and wiring for
continuity, shorts or grounds. Replace
solenoid and relay if faulty. Repair wiring
and connectors as necessary.
HARSH 1-2 OR 2-3
SHIFTSLockup Solenoid Malfunction. Remove valve body and replace solenoid
assembly.
NO START IN PARK OR
NEUTRAL1. Gearshift Linkage/Cable
Misadjusted.1. Adjust linkage/cable.
2. Neutral Switch Wire Open/Cut. 2. Check continuity with test lamp. Repair
as required.
3. Neutral Switch Faulty. 3. Refer to service section for test and
replacement procedure.
4. Neutral Switch Connect Faulty. 4. Connectors spread open. Repair.
5. Valve Body Manual Lever
Assembly Bent/Worn/Broken.5. Inspect lever assembly and replace if
damaged.
21 - 30 31TH AUTOMATIC TRANSAXLERS
31TH AUTOMATIC TRANSAXLE (Continued)
ProCarManuals.com

CONDITION POSSIBLE CAUSES CORRECTION
NO REVERSE (OR SLIPS
IN REVERSE)1. Direct Clutch Pack (front clutch)
Worn.1. Disassemble unit and rebuild clutch
pack.
2. Rear Band Misadjusted. 2. Adjust band.
3. Front Clutch Malfunctioned/Burnt. 3. Air pressure test clutch operation.
Remove and rebuild if necessary.
OIL LEAKS (ITEMS
LISTED REPRESENT
POSSIBLE LEAK POINTS
AND SHOULD ALL BE
CHECKED.1. Fluid Lines and Fittings Loose/
Leaks/Damaged.1. Tighten fittings. If leaks persist, replace
fittings and lines if necessary.
2. Filler Tube (where tube enters
case) Leaks/Damaged.2. Replace tube seal. Inspect tube for
cracks in tube.
3. Pressure Port Plug Loose
Loose/Damaged.3. Tighten to correct torque. Replace plug
or reseal if leak persists.
4. Pan Gasket Leaks. 4. Tighten pan screws to 150 inch pounds.
If leaks persist, replace gasket. Do no over
tighten screws.
5. Valve Body Manual Lever Shaft
Seal Leaks/Worn.5. Replace shaft seal.
6. Rear Bearing Access Plate Leaks. 6. Replace gasket. Tighten screws.
7. Gasket Damaged or Bolts are
Loose.7. Replace bolts or gasket or tighten both.
8. Adapter/Extension Gasket
Damaged Leaks/Damaged.8. Replace gasket.
9. Neutral Switch Leaks/Damaged. 9. Replace switch and gasket.
10. Converter Housing Area Leaks. 10. Check for leaks at seal caused by worn
seal or burr on converter hub (cutting seal),
worn bushing, missing oil return, oil in front
pump housing or hole plugged. Check for
leaks past O-ring seal on pump or past
pump-to-case bolts; pump housing porous,
oil coming out vent due to overfill or leak
past front band shaft access plug.
11. Pump Seal Leaks/Worn/
Damaged.11. Replace seal.
12. Torque Converter Weld
Leak/Cracked Hub.12. Replace converter.
13. Case Porosity Leaks. 13. Replace case.
DIAGNOSIS AND TESTING - ROAD TEST
Prior to performing a road test, check the fluid
level and throttle valve cable adjustments.
During the road test, the transaxle should be oper-
ated in each position to check for slipping and any
variation in shifting.
If vehicle operates at high speeds, but has poor
acceleration, the converter's overrunning clutch may
be slipping. If acceleration is normal, but high throt-
tle opening is needed for high speeds, the stator
clutch may have seized.Observe closely for slipping or engine speed flare-
up. Slipping or flare-up in any gear usually indicates
clutch, band, or overrunning clutch problems. If the
condition is far advanced, an overhaul will probably
be necessary to restore normal operation.
In most cases, the clutch or band that is slipping
can be determined by noting the transaxle operation
in all selector positions and then comparing which
internal units are applied in those positions. The Ele-
ments±in±Use Chart provides a basis for road test
analysis.
RS31TH AUTOMATIC TRANSAXLE21-31
31TH AUTOMATIC TRANSAXLE (Continued)
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