REMOVAL
(1) Disconnect negative battery cable.
(2) Raise vehicle on hoist.
(3) Remove oil pan (Refer to 9 - ENGINE/LUBRI-
CATION/OIL PAN - REMOVAL).
(4) Remove balance shaft assembly (Fig. 89).
INSTALLATION
(1)Before installation of the balance shaft assembly,
the # 1 cylinder must be brought to TDC. Using special
tool VM.1051, roll engine over by hand until tool can be
inserted into engine block locking flywheel from turning
(Fig. 90). Once the # 1 cylinder is brought to TDC, the
balance shaft assembly can be installed.
(2) With balance shaft assembly on work bench.
Insert special tool VM.1056 into balance shaft assem-bly (Fig. 91). This will ensure proper balance shaft
and crankshaft timing after assembly.
Fig. 89 BALANCE SHAFT ASSEMBLY
1 - BALANCE SHAFT
2 - OIL JET RETAINING BOLT
3 - OIL JET
4 - ENGINE BLOCK
5 - CRANKSHAFT
6 - BALANCE SHAFT RETAINING BOLTS
7 - OIL DIPSTICK TUBE RETAINER
8 - RUBBER BUSHING
9 - RETAINING BOLT
Fig. 90 TDC AND 90 DEGREES AFTER TDC
ALIGNMENT PIN LOCATION
1 - ENGINE BLOCK
2 - VM.1051 TDC PIN OR VM.1068 90 DEGREES ATDC PIN
3 - FLYWHEEL
Fig. 91 BALANCE SHAFT ALIGNMENT PIN VM.1056
1 - VM.1056
2 - BALANCE SHAFT ASSEMBLY
RGENGINE9a-55
BALANCE SHAFT (Continued)
ProCarManuals.com
ASSEMBLY...........................115
SHIFT INTERLOCK SOLENOID
DESCRIPTION........................115
OPERATION..........................115
DIAGNOSIS AND TESTING - BRAKE/
TRANSMISSION SHIFT INTERLOCK
SOLENOID..........................117
REMOVAL............................117
INSTALLATION........................118
SOLENOID - TCC
DESCRIPTION........................119
OPERATION..........................119
REMOVAL............................119
INSTALLATION........................120
THROTTLE VALVE CABLE
REMOVAL............................120
INSTALLATION........................121
ADJUSTMENTS
THROTTLE VALVE LINKAGE
ADJUSTMENT.......................122
TORQUE CONVERTER
DESCRIPTION........................122
OPERATION..........................126
REMOVAL............................127
INSTALLATION........................127
TRANSFER SYSTEM - OUTPUT SHAFT/GEAR/
BEARING
REMOVAL............................128INSTALLATION........................131
ADJUSTMENTS
ADJUSTMENT - OUTPUT SHAFT BEARING . 135
TRANSFER SYSTEM - TRANSFER SHAFT/
GEAR/BEARING
REMOVAL............................137
INSTALLATION........................141
ADJUSTMENTS
ADJUSTMENT - TRANSFER SHAFT
BEARING...........................145
VALVE BODY
REMOVAL............................146
DISASSEMBLY........................148
CLEANING...........................154
INSPECTION.........................155
ASSEMBLY...........................155
INSTALLATION........................158
ADJUSTMENTS
HYDRAULIC CONTROL PRESSURE
ADJUSTMENTS......................160
VEHICLE SPEED SENSOR/PINION GEAR
REMOVAL............................160
INSTALLATION........................160
31TH AUTOMATIC
TRANSAXLE
DESCRIPTION
This transaxle combines torque converter, three
speed transmission, final drive gearing, and differen-
tial into a front wheel drive system.
Within this transaxle, there are three 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 between the main rotating parts
in these three areas are held precise to maintain a
low noise level.
The torque converter, transaxle area, and differen-
tial are housed in an integral aluminum die casting.
The differential oil sump is common with the
transaxle sump. Separate filling of the differen-
tial is NOT necessary.
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 a remote cooler. There are two types of
coolers used. An oil-to-water type cooler located in
the radiator side tank and/or an oil-to-air heatexchanger. 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 assembly.
Engine torque is transmitted to the torque con-
verter and 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 section.
The transaxle consists of:
²Two multiple-disc clutches
²An overrunning clutch
²Two servos
²A hydraulic accumulator
²Two bands
²Two planetary gear sets
This provides three forward ratios and a reverse
ratio. The common sun gear of the planetary gear
sets is connected to the front clutch by a driving
shell. The driving shell is splined to the sun gear and
front clutch retainer. The hydraulic system consists
of an oil pump and a single valve body which con-
tains 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 helical gears to
the transfer shaft. This gear set is a factor in the
transaxle final drive (axle) ratio. The shaft also car-
21 - 22 31TH AUTOMATIC TRANSAXLERS
ProCarManuals.com
FLUID
STANDARD PROCEDURE
STANDARD PROCEDURE - FLUID LEVEL AND
CONDITION CHECK
NOTE: The transmission and differential sump have
a common oil sump with a communicating opening
between the two.
FLUID LEVEL CHECK
The torque converter fills in both the P Park and N
Neutral positions. Place the selector lever in P Park
to be sure that the fluid level check is accurate.The
engine should be running at idle speed for at
least one minute, with the vehicle on level
ground. This will assure complete oil level sta-
bilization between differential and transmis-
sion.The fluid should be at normal operating
temperature (approximately 82 C. or 180 F.). The
fluid level is correct if it is in the HOT region (cross-
hatched area) on the fluid level indicator (Fig. 165).
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 overheat-
ing, fluid oxidation, and varnishing. This can inter-
fere with normal valve, clutch, and servo operation.
Foaming can also result in fluid escaping from thetransaxle dipstick where it may be mistaken for a
leak.
FLUID CONDITION
Along with fluid level, it is important to check the
condition of the fluid. MopartATF+4 (Automatic
Transmission Fluid-Type 9602) when new is red in
color. The ATF is dyed red so it can be identified from
other fluids used in the vehicle such as engine oil or
antifreeze. The red color is not permanent and is not
an indicator of fluid condition. As the vehicle is
driven, the ATF will begin to look darker in color and
may eventually become brown.This is normal.
ATF+4 also has a unique odor that may change with
age. Consequently,odor and color cannot be used
to indicate the fluid condition, or the need for a
fluid change.
After the fluid has been checked, seat the dipstick
fully to seal out water and dirt.
STANDARD PROCEDURE - FLUID AND FILTER
CHANGE
NOTE: For the recommended maintenance (fluid/fil-
ter change) intervals for this transaxle, (Refer to
LUBRICATION & MAINTENANCE/MAINTENANCE
SCHEDULES - DESCRIPTION)
NOTE: Only fluids of the type labeled MoparTATF+4
(Automatic Transmission Fluid) Type 9602 should
be used. A filter change should be made at the time
of the transmission oil change. The magnet (on the
inside of the oil pan) should also be cleaned with a
clean, dry cloth.
NOTE: If the transaxle is disassembled for any rea-
son, the fluid and filter should be changed.
FLUID/FILTER SERVICE (RECOMMENDED)
(1) Raise vehicle on a hoist. Place a drain con-
tainer 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) Remove oil filter-to-valve body screws (Fig.
166).
(4) Remove oil filter and gasket (Fig. 167).
(5) Install a new filter and gasket (Fig. 167).
(6) Clean the oil pan and magnet. Reinstall pan
using new MopartSilicone Rubber Adhesive Sealant.
Torque oil pan bolts to 19 N´m (165 in. lbs.).
(7) Pour four quarts of MopartATF+4 (Automatic
Transmission Fluid-Type 9602) through the dipstick
opening.
Fig. 165 Fluid Level Indicator Markings
1 - TRANSAXLE DIPSTICK
RS31TH AUTOMATIC TRANSAXLE21-99
ProCarManuals.com
(8) Start engine and allow to idle for at least one
minute. Then, with parking and service brakes
applied, move selector lever momentarily to each
position, ending in the park or neutral position.
(9) Check the transaxle fluid level and add an
appropriate amount to bring the transaxle fluid level
to 3mm (1/8 in.) below the ªADDº mark on the dip-
stick (Fig. 168).
(10) Recheck the fluid level after the transaxle has
reached normal operating temperature (180ÉF.).
(Refer to 21 - TRANSMISSION/TRANSAXLE/AUTO-
MATIC - 31TH/FLUID - STANDARD PROCEDURE)(11) To prevent dirt from entering transaxle, make
certain that dipstick is fully seated into the dipstick
opening.
DIPSTICK TUBE FLUID SUCTION METHOD
(ALTERNATIVE)
(1) When performing the fluid suction method,
make sure the transaxle is at full operating temper-
ature.
(2) To perform the dipstick tube fluid suction
method, use a suitable fluid suction device (VaculaŸ
or equivalent).
(3) Insert the fluid suction line into the dipstick
tube.
NOTE: Verify that the suction line is inserted to the
lowest point of the transaxle oil pan. This will
ensure complete evacuation of the fluid in the pan.
(4) Follow the manufacturers recommended proce-
dure and evacuate the fluid from the transaxle.
(5) Remove the suction line from the dipstick tube.
(6) Pour four quarts of MopartATF+4 (Automatic
Transmission FluidÐType 9602) through the dipstick
opening.
(7) Start engine and allow to idle for at least one
minute. Then, with parking and service brakes
applied, move selector lever momentarily to each
position, ending in the park or neutral position.
(8) Check the transaxle fluid level and add an
appropriate amount to bring the transaxle fluid level
to 3mm (1/8 in.) below the ªADDº mark on the dip-
stick (Fig. 168).
(9) Recheck the fluid level after the transaxle has
reached normal operating temperature (180ÉF.).
(Refer to 21 - TRANSMISSION/TRANSAXLE/AUTO-
MATIC - 31TH/FLUID - STANDARD PROCEDURE)
(10) To prevent dirt from entering transaxle, make
certain that dipstick is fully seated into the dipstick
opening.
Fig. 166 Oil Filter Screws
1 - SCREWDRIVER HANDLE
2 - SPECIAL TOOL L-4553
3 - OIL FILTER SCREWS (2)
4 - OIL FILTER
Fig. 167 Oil Filter and Gasket
1 - OIL FILTER
2 - GASKET
3 - VALVE BODY
Fig. 168 Dipstick Markings
1 - TRANSAXLE DIPSTICK
21 - 100 31TH AUTOMATIC TRANSAXLERS
FLUID (Continued)
ProCarManuals.com
FLUID
STANDARD PROCEDURE
FLUID LEVEL AND CONDITION CHECK
NOTE: Only transmission fluid of the type labeled
Mopar ATF+4 (Automatic Transmission Fluid±Type
9602) should be used in this transaxle.
FLUID LEVEL CHECK
The transmission sump has a fluid level indicator
(dipstick) to check oil similar to most automatic
transmissions. It is located on the left side of the
engine. Be sure to wipe all dirt from dipstick handle
before removing.
The torque converter fills in both the P Park and N
Neutral positions. Place the selector lever in P Park
to be sure that the fluid level check is accurate.The
engine should be running at idle speed for at
least one minute, with the vehicle on level
ground.At normal operating temperature 82É C
(180É F), the fluid level is correct if it is in the HOT
region on the oil level indicator (Fig. 210). The fluid
level should be within the COLD region of the dip-
stick at 27É C (80É F) fluid temperature.
FLUID LEVEL CHECK USING DRB
NOTE: Engine and Transaxle should be at normal
operating temperature before performing this proce-
dure.
(1) Start engine and apply parking brake.
(2)
Hook up DRB scan tool and select transmission.
(3) Select sensors.
(4) Read the transmission temperature value.
(5) Compare the fluid temperature value with the
fluid temperature chart (Fig. 211).
Fig. 210 Fluid Level Indicator
1 - FLUID LEVEL INDICATOR
Fig. 211 Transmission Fluid Temperature Chart
1 - MAX. LEVEL
2 - MIN. LEVEL
RS41TE AUTOMATIC TRANSAXLE21 - 249
ProCarManuals.com
(6) Adjust transmission fluid level shown on the
indicator according to the chart.
(7) Check transmission for leaks.
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, air bubbles can cause overheating
and/or fluid oxidation, and varnishing. This can
interfere with normal valve, clutch, and accumulator
operation. Foaming can also result in fluid escaping
from the transaxle vent where it may be mistaken
for a leak.
FLUID CONDITION
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 recondition is proba-
bly required. Be sure to examine the fluid on the dip-
stick closely. If there is any doubt about its condition,
drain out a sample for a double check.
MopartATF+4 (Automatic Transmission Fluid-
Type 9602) when new is red in color. The ATF is dyed
red so it can be identified from other fluids used in
the vehicle such as engine oil or antifreeze. The red
color is not permanent and is not an indicator of fluid
condition. As the vehicle is driven, the ATF will begin
to look darker in color and may eventually become
brown.This is normal.ATF+4 also has a unique
odor that may change with age. Consequently,odor
and color cannot be used to indicate the fluid
condition or the need for a fluid change.
After the fluid has been checked, seat the dipstick
fully to seal out water and dirt.
STANDARD PROCEDURE - FLUID AND FILTER
SERVICE
NOTE: Refer to the maintenance schedules in
LUBRICATION and MAINTENANCE, or the vehicle
owner's manual, for the recommended maintenance
(fluid/filter change) intervals for this transaxle.
NOTE: Only fluids of the type labeled MoparTATF+4
(Automatic Transmission Fluid) Type 9602 should
be used. A filter change should be made at the time
of the transmission oil change. The magnet (on the
inside of the oil pan) should also be cleaned with a
clean, dry cloth.NOTE: If the transaxle is disassembled for any rea-
son, the fluid and filter should be changed.
FLUID/FILTER SERVICE (RECOMMENDED)
(1) Raise vehicle on a hoist. Refer to LUBRICA-
TION and MAINTENANCE for proper procedures.
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 o-ring on bottom of the
valve body (Fig. 212).
(4) Clean the oil pan and magnet. Reinstall pan
using new Mopar Silicone Adhesive sealant. Tighten
oil pan bolts to 19 N´m (165 in. lbs.).
(5) Pour four quarts of MopartATF+4 (Automatic
Transmission Fluid) Type 9602 through the dipstick
opening.
(6) Start engine and allow to idle for at least one
minute. Then, with parking and service brakes
applied, move selector lever momentarily to each
position, ending in the park or neutral position.
Fig. 212 Filter and O-Ring
1 - OIL FILTER
2 - O-RING
21 - 250 41TE AUTOMATIC TRANSAXLERS
FLUID (Continued)
ProCarManuals.com
(7) Check the transaxle fluid level and add an
appropriate amount to bring the transaxle fluid level
to 3mm (1/8 in.) below the lowest mark on the dip-
stick (Fig. 213).
(8) Recheck the fluid level after the transaxle has
reached normal operating temperature (180ÉF.). Refer
to Fluid Level and Condition Check for the proper
fluid fill procedure.
(9) To prevent dirt from entering transaxle, make
certain that dipstick is fully seated into the dipstick
opening.
DIPSTICK TUBE FLUID SUCTION METHOD
(ALTERNATIVE)
(1) When performing the fluid suction method,
make sure the transaxle is at full operating temper-
ature.
(2) To perform the dipstick tube fluid suction
method, use a suitable fluid suction device (VaculaŸ
or equivalent).
(3) Insert the fluid suction line into the dipstick
tube.
NOTE: Verify that the suction line is inserted to the
lowest point of the transaxle oil pan. This will
ensure complete evacuation of the fluid in the pan.
(4) Follow the manufacturers recommended proce-
dure and evacuate the fluid from the transaxle.
(5) Remove the suction line from the dipstick tube.
(6) Pour four quarts of MopartATF+4 (Automatic
Transmission Fluid) Type 9602 through the dipstick
opening.
(7) Start engine and allow to idle for at least one
minute. Then, with parking and service brakes
applied, move selector lever momentarily to each
position, ending in the park or neutral position.(8) Check the transaxle fluid level and add an
appropriate amount to bring the transaxle fluid level
to 3mm (1/8 in.) below the lowest mark on the dip-
stick (Fig. 213).
(9) Recheck the fluid level after the transaxle has
reached normal operating temperature (180ÉF.).
(Refer to 21 - TRANSMISSION/TRANSAXLE/AUTO-
MATIC - 41TE/FLUID - STANDARD PROCEDURE)
(10) To prevent dirt from entering transaxle, make
certain that dipstick is fully seated into the dipstick
opening.
GEAR SHIFT CABLE
REMOVAL
(1) Disconnect battery cables.
(2) Remove battery shield.
(3) Remove battery.
(4) Remove speed control servo and position out of
way.
(5) Disconnect gear shift cable at manual valve
lever (Fig. 214).
(6) Disconnect gear shift cable from upper mount
bracket (Fig. 214).
Fig. 213 Fluid Level Indicator
1 - FLUID LEVEL INDICATOR
Fig. 214 Gearshift Cable at Transaxle - Typical
1 - MANUAL VALVE LEVER
2 - GEAR SHIFT CABLE
3 - UPPER MOUNT BRACKET
RS41TE AUTOMATIC TRANSAXLE21 - 251
FLUID (Continued)
ProCarManuals.com