2002 CHRYSLER CARAVAN shaft

(5) Reinstall gears to pump body and measure
outer gear-to-pocket clearance with a feeler gauge
(Fig. 184).Outer gear-to-pocket clearance should
be within 0.045-0.141 mm (0.0018-0.0056 in.).
(6) Measure both inner and outer gear side clear-
ance with PlastigageŸ. If PlastigageŸ is not avail-
able, measure across the pump body with a straight
edge and feeler gauge.
(a) Position an appropriate piece of PlastigageŸ
across both gears.
(b) Align the plastigage to a flat area on the
reaction shaft housing.
(c) Install the reaction shaft support to the
pump housing and torque to 28 N´m (250 in. lbs.).
(d) Separate the reaction shaft housing from the
pump housing and measure the PlastigageŸ fol-
lowing the instructions supplied with it.Inner
and outer gear side clearance should be
within 0.020-0.046 mm (0.0008-0.0018 in.).
ASSEMBLY
(1) Install inner and outer gears to pump body
(Fig. 183). Lubricate gears with MopartATF+4
(Automatic Transmission Fluid-Type 9602).
(2) Install reaction shaft support to pump body
and align holes.
(3) Install and torque reaction shaft support-to-
pump body bolts to 28 N´m (250 in. lbs.).
PARK/NEUTRAL POSITION
SWITCH
DIAGNOSIS AND TESTING - PARK/NEUTRAL
POSITION SWITCH
The park/neutral starting switch is the center ter-
minal of the 3 terminal switch. It provides ground for
the starter solenoid circuit through the selector lever
in only Park (P) and Neutral (N) positions.
(1) To test switch, remove wiring connector from
switch and test for continuity between center pin of
switch and transaxle case. Continuity should exist
only when transaxle is in Park or Neutral.
(2) Check gearshift cable adjustment before replac-
ing a switch which tests bad.
REMOVAL
(1) Unscrew switch from transaxle case allowing
fluid to drain into a container. Move selector lever to
Park, then to Neutral position, and inspect to see the
switch operating lever fingers are centered in switch
opening.
INSTALLATION
(1) Screw the switch with a new seal into trans-
axle case and tighten to 33 N´m (24 ft. lbs.). Retest
switch with the test lamp.
(2) Add fluid to transaxle to bring up to proper
level.
(3) The back-up lamp switch circuit is through the
two outside terminals of the 3 terminal switch.
(4) To test switch, remove wiring connector from
switch and test for continuity between the two out-
side pins.
(5) Continuity should exist only with transaxle in
Reverse position.
(6) No continuity should exist from either pin to
the case.Fig. 184 Measuring Pump Outer Gear-to-Pocket
Clearance
1 - FEELER GAUGE
2 - OUTER GEAR
RS31TH AUTOMATIC TRANSAXLE21 - 107
OIL PUMP (Continued)
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(4) Install a NEW front planetary gear snap ring
and #4 thrust washer (Fig. 193).
SEAL - OIL PUMP
REMOVAL
The pump oil seal can be replaced without remov-
ing the pump and reaction shaft support assembly
from the transaxle case.
(1) Screw seal remover Tool C-3981-B into seal
(Fig. 194), then tighten screw portion of tool to with-
draw the seal.
INSTALLATION
The pump oil seal can be replaced without remov-
ing the pump and reaction shaft support assembly
from the transaxle case.
(1) To install a new seal, place seal in opening of
the pump housing (lip side facing inward). Using Tool
C-4193 and Handle Tool C-4171, drive new seal into
housing until tool bottoms (Fig. 195).
Fig. 193 Front Planetary Gear Snap Ring and No. 4
Thrust Washer
1 - SNAP RING
2 - #4 THRUST WASHER
3 - SNAP RING
4 - FRONT PLANETARY GEAR ASSEMBLY
Fig. 194 Remove Pump Oil Seal
1 - PUMP OIL SEAL
2 - OIL SEAL REMOVER TOOL C-3981-B
3 - OIL PUMP
Fig. 195 Install Pump Oil
1 - OIL PUMP
2 - OIL SEAL INSTALLER TOOL C-4193
3 - SPECIAL TOOL HANDLE C-4171
21 - 110 31TH AUTOMATIC TRANSAXLERS
PLANETARY GEARTRAIN (Continued)
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ADJUSTMENTS
THROTTLE VALVE LINKAGE ADJUSTMENT
The throttle valve linkage adjustment is very
important to proper transaxle operation. This adjust-
ment positions a valve which controls shift speed,
shift quality, and part throttle downshift sensitivity.
If the setting is too short, early shifts and slippage
between shifts may occur. If the setting is too long,
shifts may be delayed and part throttle downshifts
may be very sensitive.
LINKAGE ADJUSTMENT PROCEDURE
(1) Perform transaxle throttle valve linkage
adjustment while engine is at normal operating tem-
perature.
(2) Using small screwdriver, disengage adjustment
lock at transaxle.
(3) Rotate lever at transaxle all the way to the left
side of vehicle against stop.
(4) Slide cable adjuster until cable core end
touches clip at throttle valve lever.
(5) Press adjuster lock (Fig. 228) to retain setting.
TORQUE CONVERTER
DESCRIPTION
The torque converter (Fig. 229) is a hydraulic
device that couples the engine crankshaft to the
transmission. The torque converter consists of an
outer shell with an internal turbine, a stator, an
overrunning clutch, an impeller and an electronically
applied converter clutch. The converter clutch pro-
vides reduced engine speed and greater fuel economy
when engaged. Clutch engagement also provides
reduced transmission fluid temperatures. The con-
verter clutch engages in third gear. The torque con-
verter hub drives the transmission oil (fluid) pump.
The torque converter is a sealed, welded unit that
is not repairable and is serviced as an assembly.
CAUTION: The torque converter must be replaced if
a transmission failure resulted in large amounts of
metal or fiber contamination in the fluid. If the fluid
is contaminated, flush the fluid cooler and lines.
Fig. 228 Throttle Valve Cable Adjustment Lock
1 - ADJUSTER LOCK
Fig. 229 Torque Converter Assembly
1 - TURBINE
2 - IMPELLER
3 - HUB
4-STATOR
5 - CONVERTER CLUTCH DISC
6 - DRIVE PLATE
21 - 122 31TH AUTOMATIC TRANSAXLERS
THROTTLE VALVE CABLE (Continued)
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TURBINE
The turbine (Fig. 231) is the output, or driven,
member of the converter. The turbine is mounted
within the housing opposite the impeller, but is not
attached to the housing. The input shaft is inserted
through the center of the impeller and splined into
the turbine. The design of the turbine is similar to
the impeller, except the blades of the turbine are
curved in the opposite direction.
Fig. 231 Turbine
1 - TURBINE VANE
2 - ENGINE ROTATION
3 - INPUT SHAFT
4 - PORTION OF TORQUE CONVERTER COVER5 - ENGINE ROTATION
6 - OIL FLOW WITHIN TURBINE SECTION
21 - 124 31TH AUTOMATIC TRANSAXLERS
TORQUE CONVERTER (Continued)
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STATOR
The stator assembly (Fig. 232) is mounted on a sta-
tionary shaft which is an integral part of the oil
pump. The stator is located between the impeller and
turbine within the torque converter case (Fig. 233).
The stator contains an over-running clutch, which
allows the stator to rotate only in a clockwise direc-
tion. When the stator is locked against the over-run-
ning clutch, the torque multiplication feature of the
torque converter is operational.
TORQUE CONVERTER CLUTCH (TCC)
The TCC (Fig. 234) was installed to improve the
efficiency of the torque converter that is lost to the
slippage of the fluid coupling. Although the fluid cou-
pling provides smooth, shock±free power transfer, it
is natural for all fluid couplings to slip. If the impel-
ler and turbine were mechanically locked together, a
zero slippage condition could be obtained. A hydraulic
piston was added to the turbine, and a friction mate-
rial was added to the inside of the front cover to pro-
vide this mechanical lock-up.
Fig. 232 Stator Components
1 - CAM (OUTER RACE)
2 - ROLLER
3 - SPRING
4 - INNER RACE
Fig. 233 Stator Location
1-STATOR
2 - IMPELLER
3 - FLUID FLOW
4 - TURBINE
Fig. 234 Torque Converter Clutch (TCC)
1 - IMPELLER FRONT COVER
2 - THRUST WASHER ASSEMBLY
3 - IMPELLER
4-STATOR
5 - TURBINE
6 - PISTON
7 - FRICTION DISC
RS31TH AUTOMATIC TRANSAXLE21 - 125
TORQUE CONVERTER (Continued)
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OPERATION
The converter impeller (Fig. 235) (driving member),
which is integral to the converter housing and bolted
to the engine drive plate, rotates at engine speed.
The converter turbine (driven member), which reacts
from fluid pressure generated by the impeller, rotates
and turns the transmission input shaft.
TURBINE
As the fluid that was put into motion by the impel-
ler blades strikes the blades of the turbine, some of
the energy and rotational force is transferred into the
turbine and the input shaft. This causes both of them
(turbine and input shaft) to rotate in a clockwise
direction following the impeller. As the fluid is leav-
ing the trailing edges of the turbine's blades it con-
tinues in a ªhinderingº direction back toward the
impeller. If the fluid is not redirected before it strikes
the impeller, it will strike the impeller in such a
direction that it would tend to slow it down.
Fig. 235 Torque Converter Fluid Operation
1 - APPLY PRESSURE 3 - RELEASE PRESSURE
2 - THE PISTON MOVES SLIGHTLY FORWARD 4 - THE PISTON MOVES SLIGHTLY REARWARD
21 - 126 31TH AUTOMATIC TRANSAXLERS
TORQUE CONVERTER (Continued)
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STATOR
Torque multiplication is achieved by locking the
stator's over-running clutch to its shaft (Fig. 236).
Under stall conditions (the turbine is stationary), the
oil leaving the turbine blades strikes the face of the
stator blades and tries to rotate them in a counter-
clockwise direction. When this happens the over±run-
ning clutch of the stator locks and holds the stator
from rotating. With the stator locked, the oil strikes
the stator blades and is redirected into a ªhelpingº
direction before it enters the impeller. This circula-
tion of oil from impeller to turbine, turbine to stator,
and stator to impeller, can produce a maximum
torque multiplication of about 2.4:1. As the turbine
begins to match the speed of the impeller, the fluid
that was hitting the stator in such as way as to
cause it to lock±up is no longer doing so. In this con-
dition of operation, the stator begins to free wheel
and the converter acts as a fluid coupling.
TORQUE CONVERTER CLUTCH (TCC)
In a standard torque converter, the impeller and
turbine are rotating at about the same speed and the
stator is freewheeling, providing no torque multipli-
cation. By applying the turbine's piston to the front
cover's friction material, a total converter engage-
ment can be obtained. The result of this engagement
is a direct 1:1 mechanical link between the engine
and the transmission.
The engagement and disengagement of the TCC
are automatic and controlled by the Powertrain Con-
trol Module (PCM). The engagement cannot be acti-
vated in the lower gears because it eliminates the
torque multiplication effect of the torque converternecessary for acceleration. Inputs that determine
clutch engagement are: coolant temperature, vehicle
speed and throttle position. The torque converter
clutch is engaged by the clutch solenoid on the valve
body. The clutch will engage at approximately 56
km/h (35 mph) with light throttle, after the shift to
third gear.
REMOVAL
(1) Remove transmission and torque converter
from vehicle. (Refer to 21 - TRANSMISSION/TRANS-
AXLE/AUTOMATIC - 31TH - REMOVAL)
(2) Place a suitable drain pan under the converter
housing end of the transmission.
CAUTION: Verify that transmission is secure on the
lifting device or work surface, the center of gravity
of the transmission will shift when the torque con-
verter is removed creating an unstable condition.
The torque converter is a heavy unit. Use caution
when separating the torque converter from the
transmission.
(3) Pull the torque converter forward until the cen-
ter hub clears the oil pump seal.
(4) Separate the torque converter from the trans-
mission.
INSTALLATION
Check converter hub and drive notches for sharp
edges, burrs, scratches, or nicks. Polish the hub and
notches with 320/400 grit paper or crocus cloth if nec-
essary. The hub must be smooth to avoid damaging
the pump seal at installation.
(1) Lubricate converter hub and oil pump seal lip
with transmission fluid.
(2) Place torque converter in position on transmis-
sion.
CAUTION: Do not damage oil pump seal or bushing
while inserting torque converter into the front of the
transmission.
(3) Align torque converter to oil pump seal open-
ing.
(4) Insert torque converter hub into oil pump.
(5) While pushing torque converter inward, rotate
converter until converter is fully seated in the oil
pump gears.
(6) Check converter seating with a scale and
straightedge (Fig. 237). Surface of converter lugs
should be 1/2 in. to rear of straightedge when con-
verter is fully seated.
(7) If necessary, temporarily secure converter with
C-clamp attached to the converter housing.
Fig. 236 Stator Operation
1 - DIRECTION STATOR WILL FREE WHEEL DUE TO OIL
PUSHING ON BACKSIDE OF VANES
2 - FRONT OF ENGINE
3 - INCREASED ANGLE AS OIL STRIKES VANES
4 - DIRECTION STATOR IS LOCKED UP DUE TO OIL PUSHING
AGAINST STATOR VANES
RS31TH AUTOMATIC TRANSAXLE21 - 127
TORQUE CONVERTER (Continued)
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(8) Install the transmission in the vehicle. (Refer
to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC
- 31TH - INSTALLATION)
(9) Fill the transmission with the recommended
fluid.
TRANSFER SYSTEM - OUTPUT
SHAFT/GEAR/BEARING
REMOVAL
NOTE: Transfer Gear should be removed for repair
of output shaft, to obtain an accurate output shaft
turning torque measurement upon reassembly.
(Refer to 21 - TRANSMISSION/TRANSAXLE/AUTO-
MATIC - 31TH/TRANSFER SYSTEM - REMOVAL)
NOTE: Transaxle geartrain must be removed to gain
access to and service output shaft. (Refer to 21 -
TRANSMISSION/TRANSAXLE/AUTOMATIC - 31TH -
DISASSEMBLY)
(1) Using a suitable punch, bend retaining strap
tabs flat to facilitate bolt removal (Fig. 238).
(2) Remove retaining strap and stirrup-to-gear
bolts (Fig. 239).
Fig. 237 Checking Torque Converter Seating
1 - SCALE
2 - STRAIGHTEDGE
Fig. 238 Bend Strap Tabs Flat
1 - RETAINING TABS
2 - STRAP
Fig. 239 Remove Strap Bolts
1 - RETAINING BOLTS
2 - STIRRUP
3 - STRAP
21 - 128 31TH AUTOMATIC TRANSAXLERS
TORQUE CONVERTER (Continued)
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