transfer shaft CHRYSLER CARAVAN 2002 Owner's Guide

(2) Gently tap on end cover ears to separate cover
from case (Fig. 31).
(3) Use special tool No. 6514 and remove the dif-
ferential bearing race located in the end cover (Fig.
32). The race must be removed to gain access to the
seal.(4) Use special tool No. 7794-A to remove seal (Fig.
33).
INSTALLATION
The power transfer unit input shaft cover seal is
the larger of the two seals located on the inside of
the end cover. The differential bearing cup must be
removed to service this seal.
(1) Clean and inspect seal area.
(2) Use special tool No. MD998803 and install seal
(Fig. 34). When installing seal the spring side of the
seal must face toward the special tool.
Fig. 31 End Cover Removal
1 - END COVER EARS
2 - HAMMER
3 - POWER TRANSFER UNIT
Fig. 32 Bearing Race Removal
1 - END COVER
2 - SPECIAL TOOL
No. 6514
Fig. 33 Seal Removal
1 - END COVER
2 - SPECIAL TOOL 7794±A
3 - SLIDE HAMMER
4 - SOFT JAW VICE
Fig. 34 Seal Installation
1 - SPECIAL TOOL No. MD998803
2 - HAMMER
3 - END COVER
21 - 14 POWER TRANSFER UNITRS
INPUT SHAFT COVER SEAL (Continued)
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(3) Reinstall the original bearing race and shim
using special tool No. 6522 (Fig. 35) and (Fig. 36).CAUTION: The original shim must be installed
behind the bearing cup to maintain proper bearing
preload.
(4) Apply MopartGasket Maker, Loctite Gasket
Eliminator No. 518 or equivalent to sealing surfaces
of end cover.
(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. 37). 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 into vehicle.
(7) Check and fill fluids as required.
Fig. 35 Bearing Shim and Race
1 - SHIM
2 - BEARING RACE
3 - END COVER
Fig. 36 Installing Bearing Race
1 - HAMMER
2 - END COVER
3 - SPECIAL TOOL No. 6522
4 - HANDLE 4171
Fig. 37 Bolt Tightening Sequence
RSPOWER TRANSFER UNIT21-15
INPUT SHAFT COVER SEAL (Continued)
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INPUT SHAFT END SEAL
REMOVAL
The input shaft end seal is located on the end of
the input shaft.
(1) Remove power transfer unit from the vehicle.
(2) Remove end cover bolts (Fig. 38).
(3) Tap on end cover ears to separate end cover
from case (Fig. 39).
(4) Pry out seal with a pry bar (Fig. 40).
INSTALLATION
The input shaft end seal is located on the end of
the input shaft.
(1) Clean and inspect seal area.
(2) Remove input shaft from housing and stand on
soft block of wood. Install input shaft end seal with
seal installer 5065 and handle C-4171.
(3) Lubricate seal lip after installing seal into
input shaft.
(4) Clean sealing surfaces of the end cover and
P.T.U. case. Apply a bead of MopartGasket Maker,
Loctite Gasket Eliminator No. 518 or equivalent.
Fig. 38 End Cover Bolts
1 - POWER TRANSFER UNIT
2 - FILL PLUG
3 - END COVER
4 - OUTPUT SHAFT
Fig. 39 Side Cover Removal
1 - END COVER EARS
2 - HAMMER
3 - POWER TRANSFER UNIT
Fig. 40 Seal Removal
1 - POWER TRANSFER UNIT
2 - PRYBAR
3 - SEAL
21 - 16 POWER TRANSFER UNITRS
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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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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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(5) Apply MopartGasket Maker or equivalent to
sealing surfaces of end cover and reinstall. Tighten
bolts to 28 N´m (250 in. lbs.)
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 into vehicle.
(7) Check and fill fluids as required.
OUTER HALF SHAFT SEAL
REMOVAL
The outer half shaft seal is located on the outside
of the end cover. The P.T.U. does not have to be
removed to replace this seal.
(1) Lift vehicle on hoist.
(2) Remove right front half shaft from vehicle.
(3) Remove seal with a chisel and hammer (Fig.
48).
INSTALLATION
The outer half shaft seal is located on the outside
of the end cover. The P.T.U. does not have to be
removed to replace this seal.
(1) Clean and inspect seal area.
(2) Install new seal with seal installer MD998334
(Fig. 49).(3) Reinstall right front half shaft.
(4) Check and fill fluids as required.
REAR COVER O-RING
REMOVAL
(1) Raise vehicle on hoist.
(2) Remove rear cover retaining bolts (Fig. 50).
Fig. 48 Seal Removal
1 - HAMMER
2 - CHISEL
3 - SEAL
4 - POWER TRANSFER UNIT
Fig. 49 Seal Installation
1 - BEARING
2 - SNAP RING PLIERS
3 - BEARING SNAP RING
Fig. 50 Rear Cover Bolts
1 - OUTPUT FLANGE SEAL
2 - REAR COVER
3 - OUTPUT SHAFT
RSPOWER TRANSFER UNIT21-19
INPUT SHAFT SEAL (Continued)
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(3) Index rear cover to the case for later reassem-
bly (Fig. 51).
(4) Pull rear cover out of the P.T.U. case (Fig. 52).(5) Remove rear cover O-Ring (Fig. 53).
INSTALLATION
(1) To install, reverse removal procedure.
Fig. 52 Rear Cover Removal
1 - POWER TRANSFER UNIT ASSEMBLY
2 - REAR COVER
3 - O-RING
Fig. 51 Mark Rear Cover
1 - REAR COVER
2 - OUTPUT SHAFT
3 - PAINT MARK
Fig. 53 O-Ring Removal
1 - REAR COVER
2 - PINION GEAR
3 - O-RING
21 - 20 POWER TRANSFER UNITRS
REAR COVER O-RING (Continued)
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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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ries the governor and parking sprag. An integral heli-
cal gear on the transfer shaft drives the differential
ring gear.
OPERATION
Transmission output is directed to an integral dif-
ferential by a transfer gear system in the following
input-to-output ratios:
FIRST 2.69:1
SECOND 1.55:1
THIRD 1.00:1
REVERSE 2.10:1
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - PRELIMINARY
DIAGNOSIS
Automatic transaxle malfunctions are usually
caused by the following general conditions:
²Improper fluid level/condition²Poor engine performance
²Improper engine or transaxle adjustments
²Transaxle hydraulic malfunctions
²Transaxle mechanical malfunctions
Diagnosis of transaxle problems should always
begin with checking the easily accessible variables:
²Fluid level and condition
²Gearshift cable adjustment
²Throttle valve cable adjustment
After verifying or adjusting these variables, road
test the vehicle to determine if the problem has been
corrected or that further diagnosis is necessary. If the
problem still exists, refer to the following diagnosis
charts to aid in determining the source or cause of
failure.
Hydraulic pressure tests should be performed
when a transaxle internal failure is suspected. The
hydraulic flow charts, in the Schematics and Dia-
grams section of this group, outline fluid flow and
hydraulic circuitry. Circuit operation is provided for
all gear ranges. Normal working pressures are also
supplied for each of the gear ranges.
21 - 24 31TH AUTOMATIC TRANSAXLERS
31TH AUTOMATIC TRANSAXLE (Continued)
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