transmission CHEVROLET DYNASTY 1993 Service Manual
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Page 1964 of 2438
CAUTION: Be sure crossover bellcrank does NOT
move when tightening adjusting screw (Fig. 10).
CAUTION: Proper torque to the crossover cable ad-
justing screw is very important (Fig. 10).
(6) Remove lock pin from gearshift housing and re-
install lock pin (so long end is up) in gear shift hous-
ing. Tighten lock pin to 8 N Im (70 in. lbs.).
(7) Check for shift into first and reverse.
(8) Gearshift mechanism and cables are now func-
tioning properly.
IN-CAR TRANSAXLE DISASSEMBLE/ASSEMBLE
The following items can be serviced without remov-
ing the transaxle from the vehicle:
² Gear shift housing
² Synchronizers
² Intermediate shaft speed gears
² Input shaft
² Reverse idler gear and shaft
² Shift forks and pads
² Shift rails ²
Roller detents
² Speedometer pinion
² All external covers
Observe following procedure:
(1) Disconnect negative cable from battery.
(2) Remove both shift cables from shift cover levers.
(3) Remove left front wheel and tire assembly and
left splash shield. (4) Place drain pan under transaxle and remove
transaxle rear end cover. (5) Push out the fifth fork roll pin and slide the fifth
fork and synchronizer sleeve off the rail/hub. (6) Remove the fifth hub snap ring, hub assembly
and speed gear. (7) Remove fifth gear nut and fifth input gear.
(8) Remove the bearing retainer plate, interlock
plate and shuttles.
CAUTION: Before removing the gearshift housing
assembly, reverse the lock pin (so the long end is
down) and insert lock pin into the same threaded
hole. This procedure will save time when the gear
shift housing assembly is reinstalled. (9) Remove selector shaft housing bolts (note the two
pilot bolts) and remove housing. (10) Remove roller detents and springs, noting that
the rollers align with the shift rails. (11) Push out the 1-2 and 3-4 lug roll pins, remove
the reverse pivot lever and fifth rail C-Clip. If a roll
pin or C-Clip falls, be sure to remove it from the
bottom of the case. (12) Pull out the fifth shift rail and remove the fifth
shift lug and interlock pin. If the pin falls, be sure to
remove it from the bottom of the case. (13) Remove the intermediate shaft ball bearing
snap ring and the bearing support plate. (14) Remove reverse shift rail and lug assembly.
(15) Remove the reverse idler shaft and gear assem-
bly. (16) Rotate the 1-2 shift lug and rail, and 3-4 shift
lug towards the front of the vehicle. (17) Firmly grasp both the input and intermediate
shaft assemblies and pull them out of the transmission
with the 1-2 and 3-4 shift rails, lugs and forks. The differential assembly can only be serviced
by removing the complete transaxle from the
vehicle because bearing preload must be reset. The components listed in the first paragraph can now
be serviced. Refer to the appropriate subassembly
recondition section.
To reassemble the transaxle in the vehicle, reverse
the above procedure using the proper sealants. Fill the
transaxle with SAE 5W-30 engine oil to the bottom of
the fill hole in the end cover.
Fig. 9 Install Cables
Fig. 10 Adjusting Crossover Cable
21 - 4 TRANSAXLE Ä
Page 1965 of 2438
TRANSAXLE REMOVAL AND INSTALLATION
Transaxle removal does not require engine re-
moval. After installing transaxle, fill transaxle to bottom of
fill plug hole with SAE 5W-30 engine oil before lower-
ing vehicle to floor. (1) Disconnect or connect negativebattery cable.
(2) Install a lifting eyeon battery ground strap bolt
on left side of engine. Then install the engine support
fixture as shown in Figure 1.
(3) Disconnect or connect gearshift cables at tran-
saxle. Disconnect speedometer. Disconnect or connect
gearshift cables bracket at transaxle. (4) Remove or install both front wheel and tire
assemblies. (5) Remove or install left front splash shield.
(6) Remove or install engine left mount from tran-
saxle.
CAUTION:Left engine mounting bolts used in posi-
tion number 1 and number 3 are the same length. The
bolt in the number 2 position is longer. If bolt number
2 is used in position number 3 it can damage the
selector shaft housing when the bolt is seated (Fig.
2).
(7) Remove or install anti-rotational link (or anti-
hop damper) from crossmember bracket. Do not re-
move bracket from transaxle .
(8) Refer to Group 2 Suspension, to remove or
install both drive shafts. When removing or installing the transaxle, it
may be helpful to use locating pins in place of the
top transaxle to engine bolts (Fig. 3).
Make the locating pins from two stock (transaxle
case to engine block) bolts as follows: Using a hacksaw,
remove bolt heads, cut slot in end of bolts for a screw
driver, and remove burrs with a grinding wheel. Install the locating pins into the engine block and
proceed with transaxle installation. After transaxle is
in place, install bolts and remove locating pins before
removing transmission jack.
Fig. 1 Engine Support Fixture
Fig. 2 Left Engine Mount Bolt Location
Fig. 3 Remove or Install Bolts
Ä TRANSAXLE 21 - 5
Page 1995 of 2438
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
Page 2000 of 2438
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
Page 2008 of 2438
GOVERNOR
To service the governor assembly in the vehicle, it
is not necessary to remove the transfer gear cover,
transfer gear, and governor support. The governor
may be serviced by removing the transaxle oil pan
and valve body assembly. With the oil pan and valve
body removed, the governor may be unbolted from
the governor support and removed. When cleaning or assembling the governor, make
sure the governor valves move freely in the bores of
the governor body.
ALUMINUM THREAD REPAIR
Damaged or worn threads in the aluminum tran-
saxle case and valve body can be repaired by the use
of Heli-Coils, or equivalent. This repair consists of
drilling out the worn-out damaged threads. Then tap-
ping the hole with a Heli-Coil tap, or equivalent, and
installing a Heli-Coil insert, or equivalent, into the
hole. This brings the hole back to its original thread
size. Heli-Coil, or equivalent, tools and inserts are
readily available from most automotive parts suppli-
ers.
OIL COOLERS AND TUBES REVERSE FLUSHING
When a transaxle failure has contaminated the
fluid, the oil cooler(s) must be flushed. The torque
converter must be replaced with an exchange unit.
This will insure that metal particles or sludged oil
are not transferred back into the reconditioned (or
replaced) transaxle.
CAUTION: If vehicle is equipped with two oil cool-
ers (one in the radiator tank, one in front of the ra-
diator) they must be flushed separately. Do not
attempt to flush both coolers at one time.
(1) Disconnect the cooler lines at the transmission.
(2) Using a hand suction gun filled with mineral
spirits, reverse flush the cooler. Force mineral spirits
into the From Cooler line of the cooler (Fig. 9) and
catch the exiting spirits from the To Coolerline.
Observe for the presence of debris in the exiting
fluid. Continue until fluid exiting is clear and free
from debris. (3) Using compressed air in intermittent spurts,
blow any remaining mineral spirits from the cooler,
again in the reverse direction. (4) To remove any remaining mineral spirits from
the cooler, one (1) quart of automatic transmission
fluid should be pumped through the cooler before re-
connecting. (5) If at any stage of the cleaning process, the
cooler does not freely pass fluid, the cooler must be
replaced.
OIL COOLER FLOW CHECK
After the new or repaired transmission has been
installed and filled to the proper level with auto-
matic transmission fluid. The flow should be checked
using the following procedure: (1) Disconnect the From coolerline at the trans-
mission and place a collecting container under the
disconnected line. (2) Run the engine at curb idle speed , with the
shift selector in neutral. (3) If the fluid flow is intermittent or it takes more
than 20 seconds to collect one quart of automatic
transmission fluid, the cooler should be replaced.
CAUTION: With the fluid set at the proper level,
fluid collection should not exceed (1) quart or inter-
nal damage to the transmission may occur.
(4) If flow is found to be within acceptable limits,
reconnect the cooler line. Then fill transmission to
the proper level, using the approved type of auto-
matic transmission fluid.
TRANSAXLE AND TORQUE CONVERTER REMOVAL
Transaxle removal does NOT require engine
removal. (1) The transaxle and torque converter must be re-
moved as an assembly; otherwise, the torque con-
verter drive plate, pump bushing, or oil seal may be
damaged. The drive plate will not support a load;
therefore, none of the weight of the transaxle should
be allowed to rest on the plate during removal. (2) Disconnect battery negative cable .
(3) Disconnect throttle linkage and shift linkage
from transaxle.
Fig. 9 Cooler Line Identification
21 - 48 TRANSAXLE Ä
Page 2010 of 2438
Remove or install starter. Remove or install lower
bell housing bolts. Carefully work transaxle and torque converter as-
sembly rearward off engine block dowels and disen- gage converter hub from end of crankshaft.
Attach a
small ``C'' clamp to edge of bell housing. This will
hold torque converter in place during transaxle
removal. Lower transaxle and remove assembly from
under the vehicle. When installing transaxle, reverse the above proce-
dure. If torque converter was removed from transaxle be
sure to align pump inner gear pilot flats with torque
converter impeller hub flats. Adjust gearshift and throttle cables.
Refill transaxle with MOPAR tATF PLUS (Auto-
matic Transmission Fluid) Type 7176.
DISASSEMBLY SUBASSEMBLY REMOVAL
Prior to removing any transaxle subassemblies,
plug all openings and thoroughly clean exterior of
the unit, preferably by steam. Cleanliness through
entire disassembly and assembly cannot be overem-
phasized. When disassembling, each part should be
Fig. 7 Remove or Install Engine Mount Bracket from Front Crossmember
Fig. 8 Remove or Install Front Mount InsulatorThrough-Bolt and Bell Housing Bolts
Fig. 9 Positioning Transmission Jack
Fig. 10 Remove or Install Left Engine Mount
Fig. 11 Remove or Install Left Engine Mount from Engine
21 - 50 TRANSAXLE Ä
Page 2045 of 2438
41TE FOUR SPEED AUTOMATIC TRANSAXLE INDEX
page page
41TE Transaxle General Diagnosis ........... 88
Aluminum Thread Repair ................... 98
Bearing Adjustment Procedure .............. 141
Clutch Air Pressure Tests .................. 95
Coolers and Tubes Reverse Flushing ......... 98
Diagnosis Chart ``B'' ....................... 90
Diagnosis Trouble Code Chart ``A'' ............ 89
Differential Repair ....................... 136
Fluid and Filter Changes ................... 93
Fluid Drain and Refill ..................... 93
Fluid Leakage-Torque Converter Housing Area . . 97
Fluid Level and Condition .................. 93
Gearshift Linkage Adjustment ............... 98
General Information ....................... 85
Hydraulic Pressure Tests ................... 94
Input Clutches-Recondition ................ 121
Oil Cooler Flow Check .................... 99 Oil Pump Seal Replace
................... 136
Park/Neutral Position Switch ............... 102
Pinion Factor Procedure .................. 104
Road Test .............................. 93
Selection of Lubricant ..................... 93
Solenoid Assembly-Replace ................ 101
Special Additives ......................... 93
Speed Sensor-Input ...................... 102
Speed Sensor-Output .................... 103
Torque Converter Clutch Break-In Procedure . . . 104
Transaxle Quick Learn Procedure ........... 103
Transaxle Recondition .................... 105
Transaxle Removal and Installation ........... 99
Transmission Control Module ............... 103
Transmission Range Switch ................ 102
Valve Body-Recondition ................... 132
GENERAL INFORMATION
The 41TE four-speed FWD transaxle uses fully-
adaptive controls. Adaptive controls are those which
perform their functions based on real-time feedback
sensor information. The transaxle uses hydraulically
applied clutches to shift a planetary gear train.
TRANSAXLE IDENTIFICATION
The 41TE transaxle identification code is printed
on a label. The label is located on the transaxle case
next to the solenoid assembly (Fig. 1). Refer to Figure 2 for an internal view of the tran-
saxle assembly.
Fig. 1 Identification Tag Location
Ä TRANSAXLE 21 - 85
Page 2047 of 2438
OPERATION
The 41TE transaxle provides forward ratios of 2.84,
1.57, 1.00, and 0.69 with torque converter clutch
available in 2nd, direct, or overdrive gear; the Re-
verse ratio is 2.21. The shift lever is conventional
with six positions: P, R, N, OD, 3, and L. When OD
is selected the transaxle shifts normally through all
four speeds with torque converter clutch available in
overdrive; this position is recommended for most
driving. The 3 position is tailored for use in hilly or
mountainous driving. When 3 is selected, the trans-
mission uses only 1st, 2nd, and direct gears with
2nd-direct shift delayed to 40 mph or greater. When
operating in 3 or L positions torque converter clutch
application occurs in direct gear for improved trans-
mission cooling under heavy loads. If high engine
coolant temperature occurs, the torque converter
clutch will also engage in 2nd gear. The L position
provides maximum engine braking for descending
steep grades. Unlike most current transaxles, up-
shifts are provided to 2nd or direct gear at peak en-
gine speeds if the accelerator is depressed. This
provides engine over-speed protection and maximum
performance.
CLUTCH AND GEAR
The transaxle consists of:
² Three multiple disc input clutches
² Two multiple disc grounded clutches
² Four hydraulic accumulators
² Two planetary gear sets
This provides four forward ratios and a reverse ra-
tio. The clutch-apply pistons were designed with cen-
trifugally balanced oil cavities so that quick response
and good control can be achieved at any speed. A
push/pull piston is incorporated for two of the three
input clutches.
CAUTION: Some clutch packs appear similar, but
they are not the same. Do not interchange clutch
components as they might fail.
HYDRAULICS
The hydraulics of the transaxle provide the manual
shift lever select function, main line pressure regula-
tion, and torque converter and cooler flow control.
Oil flow to the friction elements is controlled directly
by four solenoid valves. The hydraulics also include a
unique logic-controlled ``solenoid torque converter
clutch control valve''. This valve locks out the 1st
gear reaction element with the application of 2nd, di-
rect, or overdrive gear elements. It also redirects the
1st gear solenoid output so that it can control torque
converter clutch operation. To regain access to 1st
gear, a special sequence of solenoid commands must
be used to unlock and move the solenoid torque con-
verter clutch control valve. This precludes any appli- cation of the 1st gear reaction element with other
elements applied. It also allows one solenoid to con-
trol two friction elements.
Small, high-rate accumulators are provided in each
controlled friction element circuit. These serve to ab-
sorb the pressure responses, and allow the controls to
read and respond to changes that are occurring.
SOLENOIDS
Since the solenoid valves perform virtually all con-
trol functions, these valves must be extremely dura-
ble and tolerant of normal dirt particles. For that
reason hardened-steel poppet and ball valves are
used. These are free from any close operating clear-
ances, and the solenoids operate the valves directly
without any intermediate element. Direct operation
means that these units must have very high output
so that they can close against the sizeable flow areas
and high line pressures. Fast response is also re-
quired to meet the control requirements. Two of the solenoids are normally-venting and two
are normally-applying; this was done to provide a de-
fault mode of operation. With no electrical power, the
transmission provides 2nd gear in OD, 3,orLshift
lever positions. All other transmission lever positions
will operate normally. The choice of 2nd gear was
made to provide adequate breakaway performance
while still accommodating highway speeds.
SENSORS
There are three pressure switches to identify sole-
noid application and two speed sensors to read input
(torque converter turbine) and output (parking sprag)
speeds. There is also a position switch to indicate the
manual shift lever position. The pressure switches
are incorporated in an assembly with the solenoids.
Engine speed, throttle position, temperature, etc., are
also observed. Some of these signals are read directly
from the engine control sensors; others are read from
a multiplex circuit with the powertrain control mod-
ule.
ELECTRONICS
The 41TE transmission control module is located
underhood in a potted, die-cast aluminum housing
with a sealed, 60-way connector.
ELECTRONIC MODULATED CONVERTER CLUTCH (EMCC)
The EMCC enables the torque converter clutch to
partially engage between 23 to 47 MPH before full
engagement at about 50 MPH and beyond. This fea-
ture is on all vehicles equipped with the 41TE tran-
saxle.
ADAPTIVE CONTROLS
These controls function by reading the input and
output speeds over 140 times a second and respond-
Ä TRANSAXLE 21 - 87
Page 2048 of 2438
ing to each new reading. This provides the precise
and sophisticated friction element control needed to
make smooth clutch-to-clutch shifts for all gear
changes. The use of overrunning clutches or other
shift quality aids are not required. As with most au-
tomatic transaxles, all shifts involve releasing one el-
ement and applying a different element. In simplified
terms, the upshift logic allows the releasing element
to slip back wards slightly to ensure that it does not
have excess capacity; the apply element is filled until
it begins to make the speed change to the higher
gear; its apply pressure is then controlled to main-
tain the desired rate of speed change until the shift
is complete. The key to providing excellent shift
quality is precision; for example, as mentioned, the
release element for upshifts is allowed to slip back-
wards slightly; the amount of that slip is typically
less than a total of 20 degrees. To achieve that pre-
cision, the transmission control module learns the
characteristics of the particular transaxle that it is
controlling. It learns the release rate of the releasing
element and the apply time of the applying element.
It also learns the rate at which the apply element
builds pressure sufficient to begin making the speed
change. This method achieves more precision than
would be possible with exacting tolerances. It can
also adapt to any changes that occur with age or en-
vironment, for example, altitude, temperature, en-
gine output, etc. For kickdown shifts, the control logic allows the re-
leasing element to slip and then controls the rate at
which the input (and engine) accelerate; when the
lower gear speed is achieved, the releasing element
reapplies to maintain that speed until the apply ele-
ment is filled. This provides quick response since the
engine begins to accelerate immediately and a
smooth torque exchange since the release element
can control the rate of torque increase. This control
can make any powertrain feel more responsive with-
out in creasing harshness. Adaptive controls respond to input speed changes. They compensate for changes in engine or friction el-
ement torque and provide good, consistent shift qual-
ity for the life of the transaxle.
ON-BOARD DIAGNOSTICS
These controls provide comprehensive, on-board
transaxle diagnostics. The information available can
aid in transaxle diagnosis. For example, apply ele-
ment buildup rate indicates solenoid performance.
Also included are self diagnostic functions. Self diag-
nostics allow the technician to test the condition of
the electronic controls. The transmission control
module continuously monitors its critical functions.
It also records any malfunctions, and the number of
engine starts since the last malfunction. This allows
the technician to use the information in the event of
a customer complaint.
41TE TRANSAXLE GENERAL DIAGNOSIS
CAUTION: Before attempting any repair on a 41TE
four speed automatic transaxle, check for diagnos-
tic trouble codes with the DRB II scan tool. Always
use the Powertrain Diagnostic Test Procedure Man-
ual.
Transaxle malfunctions may be caused by these
general conditions:
² Poor engine performance
² Improper adjustments
² Hydraulic malfunctions
² Mechanical malfunctions
² Electronic malfunctions
Diagnosis of these problems should always begin
by checking the easily accessible variables: fluid
level and condition, gearshift 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 checks
should be performed.
21 - 88 TRANSAXLE Ä
Page 2053 of 2438
FLUID LEVEL AND CONDITION
The transmission and differential sump have a
common oil sump with a communicating opening
between the two. The torque converter fills in both the PPark and N
Neutral positions. Place the selector lever in PPark to
check the fluid level. The engine should be running
at idle speed for at least one minute, with the
vehicle on level ground. This will assure com-
plete oil level stabilization between differential
and transmission. The fluid should be at normal
operating temperature (approximately 82 C. or 180 F.).
The fluid level is correct if it is in the HOTregion
(cross-hatched area) on the oil level indicator. 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 over heat-
ing, fluid oxidation, and varnishing, which can inter-
fere with normal valve, clutch, and accumulator opera-
tion. Foaming can also result in fluid escaping from the
transaxle vent 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
the 41TE transaxle. MOPAR tATF PLUS (Automatic
Transmission FluidÐtype 7176) should be used to aid
in assuring optimum transmission performance. Flu-
ids of the type labeled DEXRON II Automatic Trans-
mission Fluid are not recommended . DEXRON II
can be used only if the recommended fluid is not
available. If more than a small amount of DEXRON II
is used shudder or shift quality problems may result. 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 transaxle, other than the
automatic transmission fluid listed above. An excep- tion 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 CHANGES
When the factory fill fluid is changed, only fluids
labeled MOPAR tATF PLUS (Automatic Transmis-
sion fluid) Type 7176 should be used. A filter change
should be made at the time of the oil change. Also
the magnet (on the inside of the oil pan) should be
cleaned with a clean, dry cloth. If the transaxle is disassembled for any reason, the
fluid and filter should be changed.
FLUID DRAIN AND REFILL
(1) Raise vehicle on a hoist (See Lubrication,
Group 0). Place a drain container with a large open-
ing, 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 O-ring on bottom of the
valve body. (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 (Au-
tomatic Transmission Fluid) Type 7176 through the
fill tube. (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 op-
erating temperature. The level should be in the HOT
region (Fig. 3).
To prevent dirt from entering transaxle, make cer-
tain that dipstick is seated into the dipstick fill tube
(Fig. 4).
ROAD TEST
Prior to performing a road test, be certain that the
fluid level and condition, and control cable adjust-
ment have been checked and approved.
Fig. 3 Oil Level Indicator
Ä TRANSAXLE 21 - 93