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. 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
RSAUTOMATIC - 31TH21 - 123
TORQUE CONVERTER (Continued)
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.
Fig. 235 Torque Converter Fluid Operation
1 - APPLY PRESSURE
2 - THE PISTON MOVES SLIGHTLY FORWARD3 - RELEASE PRESSURE
4 - THE PISTON MOVES SLIGHTLY REARWARD
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
21 - 124 AUTOMATIC - 31THRS
TORQUE CONVERTER (Continued)
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 converter
necessary 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.
(8) Install the transmission in the vehicle. (Refer
to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC
- 31TH - INSTALLATION)
(9) Fill the transmission with the recommended
fluid.
Fig. 237 Checking Torque Converter Seating
1 - SCALE
2 - STRAIGHTEDGE
RSAUTOMATIC - 31TH21 - 125
TORQUE CONVERTER (Continued)
VALVE BODY
DESCRIPTION..........................289
OPERATION............................290
REMOVAL.............................290DISASSEMBLY..........................292
ASSEMBLY............................296
INSTALLATION..........................301
AUTOMATIC - 41TE
TRANSAXLE IDENTIFICATION
DESCRIPTION
The 41TE (Fig. 1) is a four-speed transaxle that is
a conventional hydraulic/mechanical assembly with
an integral differential, and is controlled with adap-
tive electronic controls and monitors. The hydraulic
system of the transaxle consists of the transaxle
fluid, fluid passages, hydraulic valves, and various
line pressure control components. An input clutch
assembly which houses the underdrive, overdrive,
and reverse clutches is used. It also utilizes separate
holding clutches: 2nd/4th gear and Low/Reverse. The
primary mechanical components of the transaxle con-
sist of the following:
²Three multiple disc input clutches
²Two multiple disc holding clutches
²Four hydraulic accumulators
²Two planetary gear sets
²Hydraulic oil pump
²Valve body
²Solenoid/Pressure switch assembly
²Integral differential assembly
Control of the transaxle is accomplished by fully
adaptive electronics. Optimum shift scheduling is
accomplished through continuous real-time sensor
feedback information provided to the Transmission
Control Module (TCM).
The TCM is the heart of the electronic control sys-
tem and relies on information from various direct
and indirect inputs (sensors, switches, etc.) to deter-
mine driver demand and vehicle operating condi-
tions. With this information, the TCM can calculate
and perform timely and quality shifts through vari-
ous output or control devices (solenoid pack, trans-
mission control relay, etc.).
The TCM also performs certain self-diagnostic
functions and provides comprehensive information
(sensor data, DTC's, etc.) which is helpful in proper
diagnosis and repair. This information can be viewed
with the DRB scan tool.
The 41TE transaxle identification code is a series
of digits printed on a bar-code label that is fixed to
the transaxle case as shown in (Fig. 2).For example, the identification code K 821 1125
1316 can be broken down as follows:
²K = Kokomo Transmission Plant
²821 = Last three digits of the transaxle part
number
²1125 = Build date
²1316 = Build sequence number
If the tag is not legible or missing, the ªPKº num-
ber, which is stamped into the transaxle case behind
the transfer gear cover, can be referred to for identi-
fication. This number differs slightly in that it con-
tains the entire transaxle part number, rather than
the last three digits.
OPERATION
Transmission output is directed to an integral dif-
ferential by a transfer gear system in the following
input-to-output ratios:
First...............................2.84 : 1
Second.............................1.57 : 1
Third..............................1.00 : 1
Overdrive...........................0.69 : 1
Reverse............................2.21 : 1
DIAGNOSIS AND TESTING - 41TE TRANSAXLE
GENERAL DIAGNOSIS
NOTE: Before attempting any repair on a 41TE four-
speed automatic transaxle, check for diagnostic
trouble codes (DTC's) using the DRB scan tool.
Refer to the Transmission Diagnostic Procedures
Manual.
Transaxle malfunctions may be caused by these
general conditions:
²Poor engine performance
²Improper adjustments
²Hydraulic malfunctions
²Mechanical malfunctions
²Electronic malfunctions
Diagnosis of these problems should always begin
by checking the easily accessible variables: fluid level
and condition, gearshift cable adjustment. Then per-
form a road test to determine if the problem has been
corrected or that more diagnosis is necessary. If the
problem persists after the preliminary tests and cor-
rections are completed, hydraulic pressure checks
should be performed.
RSAUTOMATIC - 41TE21 - 159
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 diagnose slip-
ping units, but the cause of the malfunction cannot
be determined. Practically any condition can be
caused by leaking hydraulic circuits or sticking
valves.
DIAGNOSIS AND TESTING - HYDRAULIC
PRESSURE TESTS
Pressure testing is a very important step in the
diagnostic procedure. These tests usually reveal the
cause of most hydraulic transaxle problems.
Before performing pressure tests, be certain that
fluid level and condition, and shift cable adjustments
have been checked and approved. Fluid must be at
operating temperature (150 to 200 degrees F.).
Install an engine tachometer, raise vehicle on hoist
which allows front wheels to turn, and position
tachometer so it can be read.
Attach 300 psi gauge (C-3293SP) to port(s)
required for test(s) being conducted. Use adapter set
L-4559 to adapt gauge(s) to transaxle.
Test port locations are shown in (Fig. 3).
TEST ONE-SELECTOR IN LOW (1st GEAR)
(1) Attach pressure gauge to the low/reverse clutch
tap.
(2) Move selector lever to the (L) position.
(3) Allow vehicle wheels to turn and increase
throttle opening to achieve an indicated vehicle speed
to 20 mph.
(4) Low/reverse clutch pressure should read 115 to
145 psi.(5) This test checks pump output, pressure regula-
tion and condition of the low/reverse clutch hydraulic
circuit and shift schedule.
TEST TWO-SELECTOR IN DRIVE (2nd GEAR)
NOTE: This test checks the underdrive clutch
hydraulic circuit as well as the shift schedule.
(1) Attach gauge to the underdrive clutch tap.
(2) Move selector lever to the 3 position.
(3) Allow vehicle wheels to turn and increase
throttle opening to achieve an indicated vehicle speed
of 30 mph.
(4) In second gear the underdrive clutch pressure
should read 110 to 145 psi.
TEST TWO A±SELECTOR IN OD (4th Gear)
NOTE: This test checks the underdrive clutch
hydraulic circuit as well as the shift schedule.
(1) Attach gauge to the underdrive clutch tap.
(2) Move selector lever to the (OD) position.
(3) Allow wheels to rotate freely and increase
throttle opening to achieve an indicated speed of 40
mph.
(4) Underdrive clutch pressure should read below
5 psi. If not, then either the solenoid assembly or
TCM is at fault.
TEST THREE-OVERDRIVE CLUTCH CHECK (3rd and
2nd Gear)
(1) Attach gauge to the overdrive clutch tap.
(2) Move selector lever to the (OD) position.
(3) Allow vehicle wheels to turn and increase
throttle opening to achieve an indicated vehicle speed
of 20 mph. Vehicle should be in 3rd gear.
(4) Overdrive clutch pressure should read 74 to 95
psi.
(5) Move selector lever to the (3) position and
increase indicated vehicle speed to 30 mph.
(6) The vehicle should be in second gear and over-
drive clutch pressure should be less than 5 psi.
(7) This test checks the overdrive clutch hydraulic
circuit as well as the shift schedule.
TEST FOUR-SELECTOR IN OVERDRIVE (4th Gear)
(1) Attach gauge to the 2/4 clutch tap.
(2) Move selector lever to the (OD) position.
(3) Allow vehicle front wheels to turn and increase
throttle opening to achieve an indicated vehicle speed
of 30 mph. Vehicle should be in 4th gear.
(4) The 2/4 clutch pressure should read 75 to 95
psi.
(5) This test checks the 2/4 clutch hydraulic cir-
cuit.
Fig. 3 Pressure Taps
1 - OVERDRIVE CLUTCH
2 - TORQUE CONVERTER OFF
3 - LOW/REVERSE CLUTCH
4 - 2/4 CLUTCH
5 - REVERSE CLUTCH
6 - UNDERDRIVE CLUTCH
21 - 162 AUTOMATIC - 41TERS
AUTOMATIC - 41TE (Continued)
TEST FIVE-SELECTOR IN OVERDRIVE (4th Gear-CC
on)
(1) Attach gauge to the torque converter clutch off
pressure tap.
(2) Move selector lever to the (OD) position.
(3) Allow vehicle wheels to turn and increase
throttle opening to achieve an indicated vehicle speed
of 50 mph. Vehicle should be in 4th gear, CC on.
CAUTION: Both wheels must turn at the same
speed.
(4) Torque converter clutch off pressure should be
less than 5 psi.
(5) This test checks the torque converter clutch
hydraulic circuit.
TEST SIX-SELECTOR IN REVERSE
(1) Attach gauges to the reverse and LR clutch
tap.
(2) Move selector lever to the (R) position.
(3) Read reverse clutch pressure with output sta-
tionary (foot on brake) and throttle opened to achieve
1500 rpm.(4) Reverse and LR clutch pressure should read
165 to 235 psi.
(5) This test checks the reverse clutch hydraulic
circuit.
TEST RESULT INDICATIONS
(1) If proper line pressure is found in any one test,
the pump and pressure regulator are working prop-
erly.
(2) Low pressure in all positions indicates a defec-
tive pump, a clogged filter, or a stuck pressure regu-
lator valve.
(3) Clutch circuit leaks are indicated if pressures
do not fall within the specified pressure range.
(4) If the overdrive clutch pressure is greater than
5 psi in Step 4 of Test Three, a worn reaction shaft
seal ring or a defective solenoid assembly is indi-
cated.
(5) If the underdrive clutch pressure is greater
than 5 psi in Step 4 of Test Two A, a defective sole-
noid assembly or TCM is the cause.
PRESSURE CHECK SPECIFICATIONS
Gear Selector
PositionActual
GearPressure Taps
Underdrive
ClutchOverdrive
ClutchReverse
ClutchTorque
Converter
Clutch Off2/4 ClutchLow/
Reverse
Clutch
Park *
PARK 0-2 0-5 0-2 60-110 0-2 115-145
0 mph
REVERSE *
REVERSE 0-2 0-7 165-235 50-100 0-2 165-235
0 mph
NEUTRAL *
NEUTRAL 0-2 0-5 0-2 60-110 0-2 115-145
0 mph
L#
FIRST 110-145 0-5 0-2 60-110 0-2 115-145
20 mph
3#
SECOND 110-145 0-5 0-2 60-110 115-145 0-2
30 mph
3#
DIRECT 75-95 75-95 0-2 60-90 0-2 0-2
45 mph
OD #
OVER-
DRIVE0-2 75-95 0-2 60-90 75-95 0-2
30 mph
OD #OVER-
DRIVE
WITH
TCC0-2 75-95 0-2 0-5 75-95 0-2
50 mph
* Engine speed at 1500 rpm
# CAUTION: Both front wheels must be turning at the same speed.
RSAUTOMATIC - 41TE21 - 163
AUTOMATIC - 41TE (Continued)
DIAGNOSIS AND TESTING - CLUTCH AIR
PRESSURE TESTS
Inoperative clutches can be located using a series
of tests by substituting air pressure for fluid pressure
(Fig. 4) (Fig. 5). The clutches may be tested by apply-
ing air pressure to their respective passages. The
valve body must be removed and Tool 6056 installed.
To make air pressure tests, proceed as follows:
NOTE: The compressed air supply must be free of
all dirt and moisture. Use a pressure of 30 psi.
Remove oil pan and valve body. See Valve body
removal.
OVERDRIVE CLUTCH
Apply air pressure to the overdrive clutch apply
passage and watch for the push/pull piston to move
forward. The piston should return to its starting
position when the air pressure is removed.
REVERSE CLUTCH
Apply air pressure to the reverse clutch apply pas-
sage and watch for the push/pull piston to move rear-
ward. The piston should return to its starting
position when the air pressure is removed.
2/4 CLUTCH
Apply air pressure to the feed hole located on the
2/4 clutch retainer. Look in the area where the 2/4
piston contacts the first separator plate and watch
carefully for the 2/4 piston to move rearward. The
piston should return to its original position after the
air pressure is removed.
LOW/REVERSE CLUTCH
Apply air pressure to the low/reverse clutch feed
hole (rear of case, between 2 bolt holes). Then, look
in the area where the low/reverse piston contacts the
first separator plate. Watch carefully for the piston to
move forward. The piston should return to its origi-
nal position after the air pressure is removed.
UNDERDRIVE CLUTCH
Because this clutch piston cannot be seen, its oper-
ation is checked by function. Air pressure is applied
to the low/reverse and the 2/4 clutches. This locks the
output shaft. Use a piece of rubber hose wrapped
around the input shaft and a pair of clamp-on pliers
to turn the input shaft. Next apply air pressure to
the underdrive clutch. The input shaft should not
rotate with hand torque. Release the air pressure
and confirm that the input shaft will rotate.
DIAGNOSIS AND TESTING - TORQUE
CONVERTER HOUSING FLUID LEAKAGE
When diagnosing converter housing fluid leaks,
three actions must be taken before repair:
(1) Verify proper transmission fluid level.
(2) Verify that the leak originates from the con-
verter housing area and is transmission fluid.
(3) Determine the true source of the leak.
Fluid leakage at or around the torque converter
area may originate from an engine oil leak (Fig. 6).
The area should be examined closely. Factory fill
fluid is red and, therefore, can be distinguished from
engine oil.
Some suspected converter housing fluid leaks may
not be leaks at all. They may only be the result of
residual fluid in the converter housing, or excess
fluid spilled during factory fill, or fill after repair.
Fig. 4 Air Pressure Test Plate
1 - TOOL 6056
2 - ACCUMULATORS
Fig. 5 Testing Reverse Clutch
1 - TOOL 6056
2 - AIR NOZZLE
21 - 164 AUTOMATIC - 41TERS
AUTOMATIC - 41TE (Continued)
(18) Remove left and right halfshaft assemblies.
(Refer to 3 - DIFFERENTIAL & DRIVELINE/HALF
SHAFT - REMOVAL)
(19) Disconnect exhaust pipe at manifold (Fig. 13).
(20) Remove cradle plate.
(21) AWD models: Remove power transfer unit.
(Refer to 21 - TRANSMISSION/TRANSAXLE/
POWER TRANSFER UNIT - REMOVAL)
(22) Remove rear mount bracket-to-transaxle case
lower (horizontal) bolt (Fig. 12).
(23) Remove rear mount heat shield (Fig. 14).
(24) Remove rear mount-to-bracket thru-bolt and
nut (Fig. 15).
(25) Remove front mount/bracket assembly.
(26) Remove starter motor.
(27) Remove lateral bending brace.(28) Remove inspection cover.
(29) Remove torque converter-to-drive plate bolts.
(30) Support engine/transaxle assembly at engine
oil pan with screw jack and wood block.
(31) Partially remove left wheelhouse splash shield
to gain access to and remove upper mount thru-bolt
(Fig. 16).
(32) Lower engine/transaxle assembly with screw
jack.
(33) Obtain helper and transmission jack. Secure
transmission jack to transaxle assembly.
(34) Remove upper mount bracket from transaxle
(Fig. 16).
(35) Remove remaining transaxle bellhousing-to-
engine bolts.
(36) Remove transaxle assembly from vehicle.
Fig. 12 Rear Mount Bracket - Typical
1 - BOLT - VERTICAL
2 - BRACKET - REAR MOUNT3 - BOLT - HORIZONTAL
RSAUTOMATIC - 41TE21 - 167
AUTOMATIC - 41TE (Continued)