clutch CHEVROLET DYNASTY 1993 Manual PDF

The PCM regulates ignition timing, air-fuel ratio,
emission control devices, cooling fan, charging sys-
tem, idle speed and speed control. Various sensors
provide the inputs necessary for the PCM to correctly
operate these systems. In addition to the sensors,
various switches also provide inputs to the PCM. All inputs to the PCM are converted into signals.
The PCM can adapt its programming to meet chang-
ing operating conditions. Fuel is injected into the intake port above the in-
take valve in precise metered amounts through elec-
trically operated injectors. The PCM fires the
injectors in a specific sequence. The PCM maintains
an air fuel ratio of 14.7 parts air to 1 part fuel by
constantly adjusting injector pulse width. Injector
pulse width is the length of time the injector is ener-
gized. The PCM adjusts injector pulse width by opening
and closing the ground path to the injector. Engine
RPM (speed) and manifold absolute pressure (air
density) are the primary inputs that determine injec-
tor pulse width.
SYSTEM DIAGNOSIS
The PCM tests many of its own input and output
circuits. If a fault is found in a major system, the in-
formation is stored in memory. Technicians can dis-
play fault information through the malfunction
indicator lamp (instrument panel Check Engine
lamp) or by connecting the DRBII scan tool. For di-
agnostic trouble code information, refer to the 3.3L/
3.8L Multi-Point Fuel InjectionÐOn-Board
Diagnostics section of this group.
CCD BUS
Various modules exchange information through a
communications port called the CCD Bus. The pow-
ertrain control module (PCM) transmits engine RPM
and vehicle load information on the CCD Bus.
POWERTRAIN CONTROL MODULE
The powertrain control module (PCM) is a digital
computer containing a microprocessor (Fig. 2). The
PCM receives input signals from various switches
and sensors that are referred to as PCM Inputs.
Based on these inputs, the PCM adjusts various en-
gine and vehicle operations through devices that are
referred to as PCM Outputs. PCM Inputs:
² Air Conditioning Controls
² Battery Voltage
² Brake Switch
² Camshaft Position Sensor
² Crankshaft Position Sensor
² Engine Coolant Temperature Sensor
² Manifold Absolute Pressure (MAP) Sensor
² Oxygen Sensor
² SCI Receive ²
Speed Control System Controls
² Throttle Position Sensor
² Transaxle Park/Neutral Switch (automatic tran-
saxle)
² Vehicle Speed Sensor
PCM Outputs:
² Air Conditioning Clutch Relay
² Generator Field
² Idle Air Control Motor
² Auto Shutdown (ASD) and Fuel Pump Relays
² Canister Purge Solenoid
² Malfunction Indicator Lamp (Check Engine Lamp)
² Data Link Connector
² Electronic EGR Transducer
² Fuel Injectors
² Ignition Coil
² Radiator Fan Relay
² Speed Control Solenoids
² Tachometer Output
Based on inputs it receives, the PCM adjusts the
EGR system, fuel injector pulse width, idle speed, ig-
nition spark advance, ignition coil dwell and canister
purge operation. The PCM regulates the cooling fan,
air conditioning and speed control systems. The PCM
changes generator charge rate by adjusting the gen-
erator field. The PCM adjusts injector pulse width (air-fuel ra-
tio) based on the following inputs.
² battery voltage
² engine coolant temperature
² exhaust gas oxygen content (oxygen sensor)
² engine speed (crankshaft position sensor)
² manifold absolute pressure
² throttle position
The PCM adjusts ignition timing based on the fol-
lowing inputs.
² engine coolant temperature
² engine speed (crankshaft position sensor)
² manifold absolute pressure
² throttle position
Fig. 2 PCM
14 - 146 FUEL SYSTEMS Ä

² transaxle gear selection (park/neutral switch)
The PCM also adjusts engine idle speed through
the idle air control motor based on the following in-
puts.
² brake switch
² engine coolant temperature
² engine speed (crankshaft position sensor)
² throttle position
² transaxle gear selection (park/neutral switch)
² vehicle speed
The auto shutdown (ASD) and fuel pump relays are
mounted externally, but turned on and off by the
PCM through the same circuit. The camshaft position sensor and crankshaft posi-
tion sensor signals are sent to the PCM. If the PCM
does not receive both signals within approximately
one second of engine cranking, it deactivates the
ASD and fuel pump relays. When these relays are
deactivated, power is shut off to the fuel injector, ig-
nition coil, oxygen sensor heating element and fuel
pump. The PCM contains a voltage converter that
changes battery voltage to a regulated 8.0 volts. The
8.0 volts power the camshaft position sensor, crank-
shaft position sensor and vehicle speed sensor. The
PCM also provides a 5.0 volts supply for the coolant
temperature sensor, manifold absolute pressure sen-
sor and throttle position sensor.
AIR CONDITIONING SWITCH SENSEÐPCM INPUT
When the air conditioning or defrost switch is put
in the ON position and the low pressure, high pres-
sure and ambient temperature switches are closed,
the PCM receives an input for air conditioning. After
receiving this input, the PCM activates the A/C com-
pressor clutch by grounding the A/C clutch relay.
BATTERY VOLTAGEÐPCM INPUT
The PCM monitors the battery voltage input to de-
termine fuel injector pulse width and generator field
control. If battery voltage is low the PCM will in-
crease injector pulse width.
BRAKE SWITCHÐPCM INPUT
When the brake switch is activated, the PCM re-
ceives an input indicating that the brakes are being
applied. the brake signal cancels speed control and
unlocks the torque convertor. The brake switch is
mounted on the brake pedal support bracket.
CAMSHAFT POSITION SENSORÐPCM INPUT
The camshaft position sensor provides cylinder
identification to the powertrain control module
(PCM) (Fig. 3). The sensor generates pulses as
groups of notches on the camshaft sprocket pass un-
derneath it (Fig. 4). The PCM keeps track of crank-
shaft rotation and identifies each cylinder by the pulses generated by the notches on the camshaft
sprocket. Four crankshaft pulses follow each group of
camshaft pulses.
When the PCM receives two camshaft pulses fol-
lowed by the long flat spot on the camshaft sprocket,
it knows that the crankshaft timing marks for cylin-
der one are next (on driveplate). When the PCM re-
ceives one camshaft pulse after the long flat spot on
the sprocket, cylinder number two crankshaft timing
marks are next. After 3 camshaft pulses, the PCM
knows cylinder four crankshaft timing marks follow.
One camshaft pulse after the three pulses indicates
cylinder five. The two camshaft pulses after cylinder
5 signals cylinder six (Fig. 4). The PCM can synchro-
nize on cylinders 1 or 4.
When metal aligns with the sensor, voltage goes
low (less than 0.5 volts). When a notch aligns with
the sensor, voltage spikes high (5.0 volts). As a group
of notches pass under the sensor, the voltage
switches from low (metal) to high (notch) then back
Fig. 3 Camshaft Position Sensor
Fig. 4 Camshaft Sprocket
Ä FUEL SYSTEMS 14 - 147

SPEED CONTROLÐPCM INPUT
The speed control system provides four separate
voltages (inputs) to the PCM. The voltages corre-
spond to the On/Off, Set, and Resume. The speed control ON voltage informs the PCM
that the speed control system has been activated.
The speed control SET voltage informs the PCM that
a fixed vehicle speed has been selected. The speed
control RESUME voltage indicates the previous fixed
speed is requested. The speed control OFF voltage
tells the PCM that the speed control system has been
deactivated. Refer to Group 8H for further speed con-
trol information.
TRANSAXLE PARK/NEUTRAL SWITCHÐPCM
INPUT
The park/neutral switch is located on the transaxle
housing (Fig. 12). It provides an input to the PCM
indicating whether the automatic transaxle is in
Park or Neutral. This input is used to determine idle
speed (varying with gear selection) and ignition tim-
ing advance. The park neutral switch is sometimes
referred to as the neutral safety switch.
THROTTLE POSITION SENSOR (TPS)ÐPCM INPUT
The Throttle Position Sensor (TPS) is mounted on
the throttle body and connected to the throttle blade
shaft (Fig. 13). The TPS is a variable resistor that
provides the PCM with an input signal (voltage). The
signal represents throttle blade position. As the posi-
tion of the throttle blade changes, the resistance of
the TPS changes. The PCM supplies approximately 5 volts to the
TPS. The TPS output voltage (input signal to the
PCM) represents the throttle blade position. The TPS
output voltage to the PCM varies from approxi-
mately 0.5 volt at minimum throttle opening (idle) to
3.5 volts at wide open throttle. Along with inputs
from other sensors, the PCM uses the TPS input to
determine current engine operating conditions. The PCM also adjust fuel injector pulse width and igni-
tion timing based on these inputs.
VEHICLE SPEED AND DISTANCE INPUTÐPCM
INPUT
The transaxle output speed sensor supplies the ve-
hicle speed and distance inputs to the PCM. The out-
put speed sensor is located on the side of the
transaxle (Fig. 12). The speed and distance signals, along with a closed
throttle signal from the TPS, determine if a closed
throttle deceleration or normal idle condition (vehicle
stopped) exists. Under deceleration conditions, the
PCM adjusts the idle air control motor to maintain a
desired MAP value. Under idle conditions, the PCM
adjusts the idle air control motor to maintain a de-
sired engine speed.
AIR CONDITIONING (A/C) CLUTCH RELAYÐPCM
OUTPUT
The PCM operates the air conditioning clutch relay
ground circuit (Fig. 14). The ignition switch supplies
battery voltage to the solenoid side of the relay.
When the A/C clutch relay energizes, battery voltage
powers the A/C compressor clutch. With the engine operating and the blower motor
switch in the On position, the PCM cycles the air
conditioning clutch on and off when the A/C switch
closes. When the PCM senses low idle speeds or wide
open throttle through the throttle position sensor, it
de-energizes the A/C clutch relay. The relay contacts
open, preventing air conditioning clutch engagement.
GENERATOR FIELDÐPCM OUTPUT
The PCM regulates the charging system voltage
Fig. 13 Throttle Position Sensor
Fig. 12 Park Neutral SwitchÐ4-Speed Electronic Automatic Transaxle
14 - 150 FUEL SYSTEMS Ä

S/C Vacuum Solenoid
A/C Clutch Relay
EGR Solenoid
Auto Shutdown Relay
Radiator Fan Relay
Purge Solenoid
Malfunction Indicator Lamp (Check Engine Lamp)
STATE DISPLAY SENSORS
Connect the DRBII scan tool to the vehicle and ac-
cess the State Display screen. Then access Sensor
Display. The following is a list of the engine control
system functions accessible through the Sensor Dis-
play screen. Oxygen Sensor Signal
Engine Coolant Temperature
Engine Coolant Temp Sensor
Throttle Position
Minimum Throttle
Battery Voltage
MAP Sensor Reading
Idle Air Control Motor Position
Adaptive Fuel Factor
Barometric Pressure
Min Airflow Idle Spd (speed)
Engine Speed
DIS Sensor Status
Fault #1 Key-On Info
Module Spark Advance
Speed Control Target
Fault #2 Key-on Info
Fault #3 Key-on Info
Speed Control Status
Speed Control Switch Voltage
Charging System Goal
Theft Alarm Status
Map Sensor Voltage
Vehicle Speed
Oxygen Sensor State
MAP Gauge Reading
Throttle Opening (percentage)
Total Spark Advance
CIRCUIT ACTUATION TEST MODE
The circuit actuation test mode checks for proper
operation of output circuits or devices which the pow-
ertrain control module (PCM) cannot internally rec-
ognize. The PCM can attempt to activate these
outputs and allow an observer to verify proper oper-
ation. Most of the tests provide an audible or visual
indication of device operation (click of relay contacts,
spray fuel, etc.). Except for intermittent conditions, if
a device functions properly during testing, assume
the device, its associated wiring, and driver circuit
working correctly.
OBTAINING CIRCUIT ACTUATION TEST
Connect the DRBII scan tool to the vehicle and ac-
cess the Actuators screen. The following is a list of
the engine control system functions accessible
through Actuators screens. Stop All Tests
Ignition Coil #1
Ignition Coil #2
Ignition Coil #3
Fuel Injector #1
Fuel Injector #2
Fuel Injector #3
Fuel Injector #4
Fuel Injector #5
Fuel Injector #6
Idle Air Control Motor Open/Close
Radiator Fan Relay
A/C Clutch Relay
Auto Shutdown Relay
EVAP Purge Solenoid
S/C Servo Solenoids
Generator Field
EGR Solenoid
All Solenoids/Relays
ASD Fuel System Test
Speed Control Vacuum Solenoid
Speed Control Vent Solenoid
THROTTLE BODY MINIMUM AIR FLOW CHECK
PROCEDURE
(1) Warm engine in Park or Neutral until the cool-
ing fan has cycled on and off at least once. (2) Ensure that all accessories are off.
(3) Shut off engine.
(4) Disconnect the PCV valve hose from the intake
manifold nipple. (5) Attach Air Metering Fitting #6457 (0.125 in.
orifice) to the intake manifold PCV nipple (Fig. 2).
(6) Disconnect the 3/16 inch idle purge line from
the throttle body nipple. Cap the 3/16 inch nipple. (7) Connect DRBII scan tool to vehicle.
(8) Restart the engine. Allow engine to idle for at
least one minute. (9) Using the DRBII scan tool, access Min. Airflow
Idle Spd.
Fig. 2 Air Metering Fitting #6457
14 - 166 FUEL SYSTEMS Ä

A-568 HEAVYÐDUTY MANUAL TRANSAXLE
The greater torque of the high output turbo engines
require a stronger transmission. It includes a die-cast
aluminum case and a stronger, coarse-pitch gear set. It
has five forward speed ratios and reverse. Gear ratios
are as follows: 1stÐ3.31, 2ndÐ1.89, 3rdÐ1.28,
4thÐ0.94, 5thÐ0.71, ReverseÐ3.14. Final drive ratio
of 3.85 was selected for maximum performance. All
forward gears are synchronized. To reduce wear, this transaxle, in common with other
manual transaxles, uses SAE 5W-30 engine oil as the
lubricant.
IDENTIFICATION
A-523, A-543, and A-568: the transaxle model, assem-
bly number, build date, and final-drive ratio are
stamped on a tag that is attached to the top of the
transaxle (Fig. 2). Certain transaxle assemblies utilize high-
strength Steel in various gears to provide adequate
life in heavy-duty applications. Therefore, it is im-
perative that the correct transaxle assembly
number is utilized when ordering service parts.
Also, be sure to reinstall this tag whenever it is
removed, so the information is available for future
service. The last eight digits of the Vehicle Identification
Number (V.I.N.) are stamped on a raised boss on top
of the clutch housing area.
GEARSHIFT LINKAGE ADJUSTMENT (CABLE
OPERATED)
Before replacing the gearshift selector cable or
crossover cable for a hard-shiftingcomplaint, dis-
connect both cables at the transaxle (Fig. 3). Then,
from the driver's seat, manually operate the gear-
Fig. 2 A-523, A-543, and A-568 Transaxle Identification
Fig. 3 Gearshift Mechanism
21 - 2 TRANSAXLE Ä

CLUTCH RELEASE BEARING INPUT SHAFT OIL SEAL
Fig. 34 Remove or Install Gear Set
Fig. 35 Gear Set
Fig. 1 Remove Retaining E-Clip
Fig. 2 Remove or Install Clutch Release Shaft
Fig. 3 Clutch Release Shaft Components
Fig. 4 Remove or Install Input Shaft Seal Retainer
21 - 14 TRANSAXLE
Ä

THREE SPEED TORQUEFLITE AUTOMATIC TRANSAXLE INDEX
page page
Accumulator-Recondition ................... 67
Aluminum Thread Repair ................... 48
Assembly Subassembly Installation ........... 57
Band Adjustment ......................... 47
Bearing Adjustment Procedures .............. 81
Clutch and Servo Air Pressure Tests .......... 43
Differential Repair ........................ 76
Disassembly Subassembly Removal .......... 50
Fluid and Filter Change .................... 40
Fluid Drain and Refill ..................... 40
Fluid Leakage-Transaxle Torque Converter Housing Area .......................... 44
Fluid Level and Condition .................. 40
Front Clutch-Recondition ................... 62
Front Planetary & Annulus Gear-Recondition .... 65
Gearshift Linkage Adjustment ............... 46
General Information ....................... 35
Governor ............................... 48
Hydraulic Control Pressure Adjustments ....... 47
Hydraulic Pressure Tests ................... 42
Kickdown Servo (Controlled Load)-Recondition . . 67 Low/Reverse Servo-Recondition
.............. 66
Oil Cooler Flow Check .................... 48
Oil Coolers and Tubes Reverse Flushing ...... 48
Oil Pump-Recondition ..................... 62
Output Shaft Repair ...................... 71
Park/Neutral Position and Back-Up Lamp Switch . 47
Parking Pawl ............................ 71
Pump Oil Seal-Replacement ................ 61
Rear Clutch-Recondition ................... 64
Road Test .............................. 40
Selection of Lubricant ..................... 40
Special Additives ......................... 40
Three Speed Torqueflite General Diagnosis ..... 36
Throttle Pressure Linkage Adjustment ......... 46
Torque Converter Clutch Solenoid Wiring Connector ............................ 40
Transaxle and Torque Converter Removal ...... 48
Transfer Shaft Repair ..................... 68
Valve Body-Recondition .................... 57
Vehicle Speed Sensor Pinion Gear ........... 47
GENERAL INFORMATION
Safety goggles should be worn at all times
when working on these transaxles. This transaxle combines a fully automatic 3 speed
transmission, final drive gearing, and differential into
a front wheel drive system. The unit is a Metric
design. The identification markings and usage of the
transaxle are charted in Diagnosis and Tests. Transaxle operation requirements are differ-
ent for each vehicle and engine combination and
some internal parts will be different to provide
for this. Therefore, when replacing parts, refer to
the seven digit part number stamped on rear of
the transaxle oil pan flange. Within this transaxle, there are 3 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 be-
tween the main rotating parts in these 3 areas are held
precise. This maintains a low noise level through
smooth accurate mesh of the gears. The torque converter, transaxle area, and differential
are housed in an integral aluminum die casting. The
differential oil sump is common with thetransaxle
sump. Separate filling of the differential is NOT nec-
essary. 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 an oil-to-water type cooler located in the
radiator side tank and/or an oil-to air heat ex- changer. 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 assem-
bly. Engine torque is transmitted to the torque con-
verter 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 sec-
tion. The transaxle consists of two multiple-disc
clutches, an overrunning clutch, two servos, a hy-
draulic accumulator, two bands, and two planetary
gear sets. They provide three forward ratios and a re-
verse ratio. The common sun gear of the planetary
gear sets is connected to the front clutch by a driving
shell. The drive shell is splined to the sun gear and
to the front clutch retainer. The hydraulic system
consists of an oil pump, and a single valve body
which contains 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 heli-
cal gears to the transfer shaft.This gear set is a
factor of the final drive (axle) ratio. The shaft also
carries the governor and parking sprag. An integral
helical gear on the transfer shaft drives the differen-
tial ring gear. The final drive gearing is completed
with one of three gear sets producing overall top gear
ratios of 2.78, 3.02, or 3.22 depending on model and
application.
Ä TRANSAXLE 21 - 35

TORQUE CONVERTER CLUTCH
The torque converter clutch is standard on all ve-
hicles. It is activated only in direct drive and is con-
trolled by the engine electronics. A solenoid on the
valve body, is powered by the powertrain control mod-
ule to activate torque converter clutch.
HYDRAULIC CONTROL SYSTEM
The hydraulic control circuits show the position of
the various valves. They indicate those under hydrau-
lic pressure for all operations of the transaxle. The hydraulic control system makes the transaxle
fully automatic, and has four important functions to
perform. In a general way, the components of any
automatic control system may be grouped into the
following basic groups: The pressure supply system, the pressure regulating
valves, the flow control valves, the clutches, and band
servos. Taking each of these basic groups or systems in turn,
the control system may be described as follows:
PRESSURE SUPPLY SYSTEM
The pressure supply system consists of an oil pump
driven by the engine through the torque converter. The
single pump furnishes pressure for all the hydraulic
and lubrication requirements. Oil pump housing
assemblies are available with preselected pump
gears.
PRESSURE REGULATING VALVES
The pressure regulating valve controls line pressure
dependent on throttle opening. The governor valve
transmits regulated pressure to the valve body (in
conjunction with vehicle speed) to control upshift and
downshift. The throttle valve transmits regulated pressure to
the transaxle (dependent on throttle position) to con-
trol upshift and downshift.
FLOW CONTROL VALVES
The manual valve provides the different transaxle
drive ranges as selected by the vehicle operator. The 1-2 shift valve automatically shifts the transaxle
from first to second or from second to first, depending
on the vehicle operation. The 2-3 shift valve automatically shifts the transaxle
from second to third or from third to second depending
on the vehicle operation. The kickdown valve makes possible a forced down-
shift from third to second, second to first, or third to
first (depending on vehicle speed). This can be done by
depressing the accelerator pedal past the detent ``feel''
near wide open throttle. The shuttle valve has two separate functions and
performs each independently of the other. The first
provides fast release of the kickdown band, and
smooth front clutch engagement, when the driver makes a
lift-footupshift from second to third. The
second function of the shuttle valve is to regulate the
application of the kickdown servo and band when
making third to second kickdown. The by-pass valve provides for smooth application of
the kickdown band on 1-2 upshifts. The torque converter clutch solenoid allows for the
electronic control of the clutch inside the torque con-
verter. It also disengages the torque converter at closed
throttle, during engine warm-up, and during part-
throttle acceleration. The switch valve directs oil to apply the torque
converter clutch in one position and releases the torque
converter clutch in the other position.
CLUTCH, BAND SERVO, AND ACCUMULATOR
The front and rear clutch pistons, and both servo
pistons are moved hydraulically to engage the clutches
and apply the bands. The pistons are released by
spring tension when hydraulic pressure is released. On
the 2-3 upshift, the kickdown servo piston is released
by spring tension and hydraulic pressure. The accumulator controls the hydraulic pressure on
the apply side of the kickdown servo during the 1-2
upshift; thereby, cushioning the kickdown band appli-
cation at any throttle position.
GEARSHIFT AND PARKING LOCK CONTROLS
The transaxle is controlled by a lever typegearshift
incorporated within the console or the steering column.
The control has six selector lever positions: P (park), R
(reverse), N (neutral), and D (drive), 2 (second), and 1
(first). The parking lock is applied by moving the
selector lever past a gate to the Pposition. Do not
apply the parking lock until the vehicle has
stopped; otherwise, a severe banging noise will
occur.
THREE SPEED TORQUEFLITE GENERAL DIAGNO-
SIS
Automatic transaxle malfunctions may be caused by
four general conditions:
² Poor engine performance
² Improper adjustments
² Hydraulic malfunctions
² Mechanical malfunctions.
Diagnosis of these problems should always begin by
checking the easily accessible variables: fluid level and
condition, gearshift cable adjustment, and throttle
pressure cable adjustment. Then perform a road test to
determine if the problem has been corrected or that
more diagnosis is necessary. If the problem exists after
the preliminary tests and corrections are completed,
hydraulic pressure tests should be performed.
21 - 36 TRANSAXLE Ä

FLUID LEVEL AND CONDITION
The transmission and differential sump have a
common oil sump with a communicating opening
between the two. Before removing the dipstick, wipe all dirt off of the
protective disc and the dipstick handle. The torque converter will fill in both the PPark or N
Neutral positions. Place the selector lever in PPark to
check fluid level. Inspect fluid level on dipstick every six months.
Allow the engine to idle for at least one minute
with vehicle on level ground. This will assure
complete oil level stabilization between differen-
tial and transmission. A properly filled transaxle
will read near the addmark when fluid temperature is
21 degrees Celsius (70 degrees Fahrenheit). When the
transaxle reaches operating temperature the fluid
should be in the HOTregion.
Low fluid level can cause a variety of conditions
because it allows the pump to take in air along with the
fluid. As in any hydraulic system, air bubbles make the
fluid spongy, therefore, pressures will be low and build
up slowly. Improper filling can also raise the fluid level too
high. When the transaxle has too much fluid, the gears
churn up foam and cause the same conditions which
occur with a low fluid level. In either case, the air bubbles can cause overheating,
fluid oxidation, and varnishing, which can interfere
with normal valve, clutch, and servo operation. Foam-
ing can also result in fluid escaping from the transaxle
vent (dipstick handle) where it may be mistaken for a
leak. Along with fluid level, it is important to check the
condition of the fluid. When the fluid smells burned,
and is contaminated with metal or friction material
particles, a complete transaxle overhaul is needed. Be
sure to examine the fluid on the dipstick closely. If
there is any doubt about its condition, drain out a
sample for a double check. After the fluid has been checked, seat the dipstick
fully to seal out water and dirt.
SELECTION OF LUBRICANT
It is important that the proper lubricant be used in
these transmissions. MOPAR tATF PLUS (Automatic
Transmission Fluid-Type 7176) should be used to aid in
assuring optimum transmission performance. Fluids of
the type labeled DEXRON II Automatic Transmission
Fluid should be used only if the recommended fluid is
not available. It is important that the transmission
fluid be maintained at the prescribed level using the
recommended fluids.
SPECIAL ADDITIVES
Chrysler Corporation does not recommend the addi-
tion of any fluids to the transmission, other than the
automatic transmission fluid listed above. An ex- ception to this policy is the use of special dyes to aid in
detecting fluid leaks. The use of transmission sealers
should be avoided, since they may adversely affect
seals.
FLUID AND FILTER CHANGE
When the factory fill fluid is changed, only
fluids of the type labeled MOPAR tATF PLUS
(Automatic Transmission fluid) Type 7176 should
be used. A band adjustment and filter change
should be made at the time of the oil change. The
magnet (on the inside of the oil pan) should also
be cleaned with a clean, dry cloth. If the transaxle is disassembled for any reason,
the fluid and filter should be changed, and the
band(s) adjusted.
FLUID DRAIN AND REFILL
(1) Raise vehicle on a hoist (See Lubrication, Group
0). Place a drain container with a large opening, under
transaxle oil pan. (2) Loosen pan bolts and tap the pan at one corner to
break it loose allowing fluid to drain, then remove the
oil pan. (3) Install a new filter and gasket on bottom of the
valve body and tighten retaining screws to 5 N Im (40
in. lbs.). (4) Clean the oil pan and magnet. Reinstall pan
using new MOPAR tAdhesive sealant. Tighten oil pan
bolts to 19 N Im (165 in. lbs.).
(5) Pour four quarts of MOPAR tATF PLUS (Auto-
matic Transmission Fluid) Type 7176 through the
dipstick opening. (6) Start engine and allow to idle for at least one
minute. Then, with parking and service brakes ap-
plied, move selector lever momentarily to each posi-
tion, ending in the park or neutral position. (7) Add sufficient fluid to bring level to 1/8 inch
below the ADD mark. Recheck fluid level after transaxle is at normal
operating temperature. The level should be in the HOT
region (Fig. 1). To prevent dirt from entering transaxle, make cer-
tain that dipstick is full seated into the dipstick open-
ing.
TORQUE CONVERTER CLUTCH SOLENOID WIRING
CONNECTOR
If wiring connector is unplugged, the torque con-
verter clutch will not operate (Fig. 2).
ROAD TEST
Prior to performing a road test, be certain that the
fluid level and condition, and control cable adjustments
have been checked and approved. During the road test, the transaxle should be oper-
ated in each position to check for slipping and any
variation in shifting.
21 - 40 TRANSAXLE Ä

If vehicle operates properly at highway speeds, but
has poor acceleration, the torque converter stator
overrunning clutch may be slipping. If through-gear
acceleration is normal, but high throttle opening is
required to maintain highway speeds, the torque con-
verter stator clutch may have seized. Both of these
stator defects require replacement of the torque con-
verter. 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. The clutch or band that is slipping can be deter-
mined by noting the transaxle operation in all selec-
tor positions. Then comparing which internal units
are applied in those positions. The Elements in Use
Chart provides a basis for road test analysis.
The rear clutch is applied in both the Dfirst gear
and 1first gear positions. Also the overrunning
clutch is applied in Dfirst gear and the low/reverse
band is applied in 1first gear position. If the tran-
saxle slips in Drange first gear, but does not slip in
1 first gear, the overrunning clutch is slipping. Sim-
ilarly, if the transaxle slips in any two forward
gears, the rear clutch is slipping. Using the same procedure, the rear clutch and
front clutch are applied in Dthird gear. If the tran-
saxle slips in third gear, either the front clutch or
the rear clutch is slipping. By selecting another gear
which does not use one of those units, the unit which
is slipping can be determined. If the transaxle also
slips in reverse, the front clutch is slipping. If the
transaxle does not slip in reverse, the rear clutch is
slipping. The process of elimination can be used to detect
any unit which slips and to confirm proper operation
of good units. Road test analysis can usually diag-
nose slipping units, but the actual cause of the mal-
function usually cannot be decided. Practically any
condition can be caused by leaking hydraulic circuits
or sticking valves.
ELEMENTS IN USE AT EACH POSITION OF THE SELECTOR LEVER
Fig. 1 Dipstick and Transaxle Vent
Fig. 2 Torque Converter Clutch Solenoid Wiring Connector
Ä TRANSAXLE 21 - 41