Chrysler Stratus Convertible. Manual — part 67

T/C REGULATOR VALVE

The torque converter regulator valve slightly regu-

lates the flow of fluid to the torque converter.

LOW/REVERSE SWITCH VALVE

The low/reverse clutch is applied from different

sources, depending on whether low (1st) gear or
reverse is selected. The low/reverse switch valve
alternates positions depending on from which direc-
tion fluid pressure is applied. By design, when the
valve is shifted by fluid pressure from one channel,
the opposing channel is blocked. The switch valve
alienates the possibility of a sticking ball check, thus
providing consistent application of the low/reverse
clutch under all operating conditions.

VENT RESERVOIR CHECK VALVE

The vent reservoir check valve is designed for

quick venting during garage shifts to prevent the
overdrive and reverse clutches from dragging. Inad-
vertent motion of the reverse/overdrive (push/pull)
piston can be caused by the unbalanced centrifugal
forces in the reverse and overdrive chambers. By
linking the overdrive and reverse vents to the vent
reservoir at the manual valve, an equal residual
pressure will be maintained, thus balancing the cen-
trifugal forces in the reverse and the overdrive cham-
bers.

ACCUMULATORS

DESCRIPTION

The 41te underdrive, overdrive, low/reverse, and

2/4 clutch hydraulic circuits each contain an accumu-
lator. An accumulator typically consists of a piston,
seals, return spring(s), and a cover or plug. The over-
drive

and

underdrive

accumulators

are

located

within the transaxle case, and are retained by the
valve body (Fig. 6).

The low reverse accumulator (Fig. 7) is also located

within the transaxle case, but the assembly is
retained by a cover and a snap-ring.

The 2/4 accumulator is located in the valve body. It

is retained by a cover and retaining screws (Fig. 8).

OPERATION

The function of an accumulator is to cushion the

application of a frictional clutch element. When pres-
surized fluid is applied to a clutch circuit, the appli-
cation force is dampened by fluid collecting in the
respective accumulator chamber against the piston
and spring(s). The intended result is a smooth, firm
clutch application.

INPUT CLUTCHES

DESCRIPTION

Three hydraulically applied input clutches are used

to drive planetary components. The underdrive, over-
drive, and reverse clutches are considered input
clutches and are contained within the input clutch
assembly (Fig. 9). The input clutch assembly also
contains:

• Input shaft

• Input hub

• Clutch retainer

• Underdrive piston

Fig. 6 Underdrive and Overdrive Accumulators

1 – RETURN SPRING
2 – UNDERDRIVE CLUTCH ACCUMULATOR
3 – SEAL RING (2)
4 – OVERDRIVE CLUTCH ACCUMULATOR

Fig. 7 Low/Reverse Accumulator Assembly

1 – ACCUMULATOR PISTON
2 – SEAL RINGS
3 – RETURN SPRINGS
4 – (NOTE NOTCH)

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DESCRIPTION AND OPERATION (Continued)

• Overdrive/reverse piston

• Overdrive hub

• Underdrive hub

OPERATION

The three input clutches are responsible for driving

different components of the planetary geartrain.

NOTE: Refer to the “Elements In Use” chart in
Diagnosis and Testing for a collective view of which
clutch elements are applied at each position of the
selector lever.

UNDERDRIVE CLUTCH

The underdrive clutch is hydraulically applied in

first, second, and third (direct) gears by pressurized
fluid against the underdrive piston. When the under-
drive clutch is applied, the underdrive hub drives the
rear sun gear.

OVERDRIVE CLUTCH

The overdrive clutch is hydraulically applied in

third (direct) and overdrive gears by pressurized fluid
against the overdrive/reverse piston. When the over-
drive clutch is applied, the overdrive hub drives the
front planet carrier.

REVERSE CLUTCH

The reverse clutch is hydraulically applied in

reverse gear only by pressurized fluid against the
overdrive/reverse piston. When the reverse clutch is
applied, the front sun gear assembly is driven.

HOLDING CLUTCHES

DESCRIPTION

Two hydraulically applied multi-disc clutches are

used to hold planetary geartrain components station-
ary while the input clutches drive others. The 2/4
and Low/Reverse clutches are considered holding
clutches and are contained at the rear of the tran-
saxle case. (Fig. 10).

OPERATION

NOTE: Refer to the “Elements In Use” chart in
Diagnosis and Testing for a collective view of which
clutch elements are applied at each position of the
selector lever.

2/4 CLUTCH

The 2/4 clutch is hydraulically applied in second

and fourth gears by pressurized fluid against the 2/4
clutch piston. When the 2/4 clutch is applied, the
front sun gear assembly is held or grounded to the
transaxle case.

Fig. 8 2/4 Accumulator Assembly

1 – VALVE BODY
2 – RETAINER PLATE
3 – DETENT SPRING
4 – SPRINGS
5 – SEALS
6 – PISTON

Fig. 9 Input Clutch Assembly

1 – INPUT SHAFT
2 – UNDERDRIVE CLUTCH
3 – OVERDRIVE CLUTCH
4 – REVERSE CLUTCH
5 – OVERDRIVE SHAFT
6 – UNDERDRIVE SHAFT

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DESCRIPTION AND OPERATION (Continued)

LOW/REVERSE CLUTCH

The Low/Reverse clutch is hydraulically applied in

park, reverse, neutral, and first gears by pressurized
fluid against the Low/Reverse clutch piston. When
the Low/Reverse clutch is applied, the front planet
carrier/rear annulus assembly is held or grounded to
the transaxle case.

PLANETARY GEARTRAIN

DESCRIPTION

The planetary geartrain is located between the

input clutch assembly and the rear of the transaxle
case. The planetary geartrain consists of two sun
gears, two planetary carriers, two annulus (ring)
gears, and one output shaft (Fig. 11).

OPERATION

The planetary geartrain utilizes two planetary gear

sets that connect the transmission input shaft to the
output shaft. Input and holding clutches drive or lock
different planetary members to change output ratio
or direction.

DIFFERENTIAL

DESCRIPTION

The 41TE differential is a conventional open

design. It consists of a ring gear and a differential
case. The differential case consists of pinion and side
gears, and a pinion shaft. The differential case is
supported in the transaxle by tapered roller bearings
(Fig. 12).

OPERATION

The differential assembly is driven by the transfer

shaft by way of the differential ring gear. The ring
gear drives the differential case, and the case drives
the driveshafts through the differential gears. The
differential pinion and side gears are supported in
the case by thrust washers and a pinion shaft. Dif-
ferential pinion and side gears make it possible for
front tires to rotate at different speeds while corner-
ing.

TRANSMISSION CONTROL MODULE

DESCRIPTION

The Transmission Control Module (TCM) is located

in the engine compartment on the left (driver’s) side
next to the Power Distribution Center (PDC) (Fig.
13).

Fig. 10 2/4 and Low/Reverse Clutches

1 – FRONT PLANET CARRIER/REAR ANNULUS
2 – 2/4 CLUTCH
3 – L/R CLUTCH
4 – REAR PLANET CARRIER/FRONT ANNULUS
5 – REAR SUN GEAR
6 – FRONT SUN GEAR ASSEMBLY

Fig. 11 Planetary Geartrain

1 – FRONT SUN GEAR ASSEMBLY
2 – #6 THRUST BEARING
3 – #7 THRUST BEARING
4 – REAR CARRIER FRONT ANNULUS ASSEMBLY
5 – REAR SUN GEAR
6 – FRONT CARRIER REAR ANNULUS ASSEMBLY
7 – FRONT SUN GEAR

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DESCRIPTION AND OPERATION (Continued)

OPERATION

The TCM is the controlling unit for all electronic

operations of the transaxle. The TCM receives infor-
mation regarding vehicle operation from both direct
and indirect inputs, and selects the operational mode

of the transaxle. Direct inputs are hardwired to, and
used specifically by the TCM. Indirect inputs origi-
nate from other components/modules, and are shared
with the TCM via the communication bus.

Some examples of direct inputs to the TCM are:
• Battery (B+) voltage

• Ignition “ON” voltage

• Transmission Control Relay (Switched B+)

• Throttle Position Sensor

• Crankshaft Position Sensor (CKP)

• Transmission Range Sensor (TRS)

• Pressure Switches (L/R, 2/4, OD)

• Transmission Temperature Sensor (Integral to

TRS)

• Input Shaft Speed Sensor

• Output Shaft Speed Sensor

• TRS Hall Effect Switch (Autostick)
Some examples of indirect inputs to the TCM

are:

• Engine/Body Identification

• Manifold Pressure

• Target Idle

• Torque Reduction Confirmation

• Speed Control ON/OFF Switch

• Engine Coolant Temperature

• Ambient/Battery Temperature

• Brake Switch Status

• DRB Communication
Based on the information received from these var-

ious inputs, the TCM determines the appropriate
shift schedule and shift points, depending on the
present operating conditions and driver demand.
This is possible through the control of various direct
and indirect outputs.

Some examples of TCM direct outputs are:
• Transmission Control Relay

• Solenoids (LR/CC, 2/4, OD and UD)

• Vehicle Speed (to PCM)

• Torque Reduction Request (to PCM)
Some examples of TCM indirect outputs are:
• Transmission Temperature (to PCM)

• PRNDL Position (to BCM)

• Autostick Display (to BCM)
In addition to monitoring inputs and controlling

outputs, the TCM has other important responsibili-
ties and functions:

• Storing and maintaining Clutch Volume Indices

(CVI)

• Storing and selecting appropriate Shift Sched-

ules

• System self-diagnostics

• Diagnostic capabilities (with DRB scan tool)

NOTE: If the TCM has been replaced, the “Quick
Learn Procedure” must be performed. Refer to
“Quick Learn Procedure” in Service Procedures of
this group.

Fig. 12 Differential Assembly

1 – DIFFERENTIAL CASE
2 – RING GEAR
3 – TRANSFER SHAFT
4 – PINION GEAR
5 – PINION SHAFT
6 – SIDE GEAR

Fig. 13 Transmission Control Module Location

(Typical)

1 – POWER DISTRIBUTION CENTER (PDC)
2 – POWERTRAIN CONTROL MODULE (PCM)
3 – TRANSMISSION CONTROL MODULE (TCM)

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DESCRIPTION AND OPERATION (Continued)