Refer to the maintenance schedules for the recom-
mended fuel filter replacement intervals.
For draining of water from canister, refer to Fuel
Filter/Water Separator Removal/Installation section.
A Water-In-Fuel (WIF) sensor is part of the fuel fil-
ter cap. Refer to Water-In-Fuel Sensor Description/
Operation.
The fuel heater is installed into the filter/separator
housing above the fuel filter. Refer to Fuel Heater
Description/Operation.
FUEL LINES
DESCRIPTION
DESCRIPTION
All fuel lines up to the fuel injection pump are con-
sidered low-pressure. This includes the fuel lines
from: the fuel tank to the fuel transfer pump, and
the fuel transfer pump to the fuel injection pump.
The fuel return lines and the fuel drain lines are also
considered low-pressure lines. High-pressure lines
are used between the fuel injection pump and the
fuel injectors. Also refer to High-Pressure Fuel Lines
Description/Operation.
DESCRIPTION - HIGH PRESSURE FUEL LINES
The high-pressure fuel lines are the 4 lines located
between the fuel injection pump and the fuel injec-
torsctor tubes. All other fuel lines are considered low-
pressure lines.
OPERATION - HIGH PRESSURE FUEL LINES
CAUTION: The high-pressure fuel lines cannot con-
tact each other or other components. Do not
attempt to weld high-pressure fuel lines or to repair
lines that are damaged. If lines are ever kinked or
bent, they must be replaced. Use only the recom-
mended lines when replacement of high-pressure
fuel line is necessary.
High-pressure fuel lines deliver fuel under
extremely high pressure from the injection pump to
the fuel injectors. The lines expand and contract from
the high-pressure fuel pulses generated during the
injection process. All high-pressure fuel lines are of
the same length and inside diameter. Correct high-
pressure fuel line usage and installation is critical to
smooth engine operation.
WARNING: USE EXTREME CAUTION WHEN
INSPECTING FOR HIGH-PRESSURE FUEL LEAKS.
INSPECT FOR HIGH-PRESSURE FUEL LEAKS WITH
A SHEET OF CARDBOARD. HIGH FUEL INJECTIONPRESSURE CAN CAUSE PERSONAL INJURY IF
CONTACT IS MADE WITH THE SKIN.
DIAGNOSIS AND TESTING - HIGH PRESSURE
FUEL LINES
High-pressure fuel line leaks can cause starting
problems and poor engine performance.
WARNING: DUE TO EXTREME FUEL PRESSURES,
USE EXTREME CAUTION WHEN INSPECTING FOR
HIGH-PRESSURE FUEL LEAKS. DO NOT GET YOUR
HAND NEAR A SUSPECTED LEAK. INSPECT FOR
HIGH-PRESSURE FUEL LEAKS WITH A SHEET OF
CARDBOARD. HIGH FUEL INJECTION PRESSURE
CAN CAUSE PERSONAL INJURY IF CONTACT IS
MADE WITH THE SKIN.
Start the engine. Move the cardboard over the
high-pressure fuel lines and check for fuel spray onto
the cardboard (Fig. 4). If a high-pressure line connec-
tion is leaking, bleed the system and tighten the con-
nection. Refer to the Air Bleed Procedure in this
group for procedures. Replace damaged, restricted or
leaking high-pressure fuel lines with the correct
replacement line.
Fig. 4 Typical Test for Leaks with Cardboard
1 - HIGH-PRESSURE LINE
2 - CARDBOARD
3 - FITTING
14a - 6 FUEL DELIVERYRG
FUEL FILTER / WATER SEPARATOR (Continued)
ProCarManuals.com
CAUTION: The high-pressure fuel lines cannot con-
tact each other or other components. Do not
attempt to weld high-pressure fuel lines or to repair
lines that are damaged. Only use the recommended
lines when replacement of high-pressure fuel line is
necessary.
FUEL TRANSFER PUMP
DESCRIPTION
The fuel transfer pump (fuel lift pump) is located
under the vehicle in front of the rear axle assembly
(Fig. 5). The 12±volt electric vane-type pump is oper-
ated and controlled by the Engine Control Module
(ECM).
OPERATION
The purpose of the fuel transfer pump is to supply
(transfer) a low-pressure fuel source:fromthe fuel
tank,throughthe fuel filter/water separator andto
the fuel injection pump. Here, the low-pressure is
raised to a high-pressure by the fuel injection pump
for operation of the high-pressure fuel injectors.
The fuel transfer pump is controlled by the Engine
Control Module(ECM). The ECM turns the fuel
transfer pump on for 30 seconds when the ignition
ket is turned ªONº.
With the ignition ªONº and fuel tranfer pump run-
ning, the low-pressure fuel pressure should be 13-17
psi.
FUEL INJECTION PUMP
DESCRIPTION
A radial-piston pump is used as the high pressure
pump for fuel pressure generation (Fig. 6).
REMOVAL
(1) Disconnect negative battery cable.
(2) Remove engine cover (Refer to 9 - ENGINE -
REMOVAL)
(3) Remove air cleaner housing assembly.
(4) Remove power steering belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
REMOVAL).
(5) Remove accessory drive belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
REMOVAL).
Fig. 5 FUEL TRANSFER(LIFT) PUMP LOCATION
1 - LIFT PUMP RETAINING BOLTS
2 - LIFT PUMP
3 - FUEL FILTER/WATER SEPARATOR HOUSING
4 - FUEL HEATER
5 - CHECK BALL
6 - O-RING
7 - FLOW DIVERTER
8 - FUEL FILTER
9 - O-RING
10 - FUEL FILTER BOWL ASSEMBLY
Fig. 6 FUEL INJECTION PUMP
1 - FUEL INJECTION PUMP
2 - INJECTION PUMP PRESSURE SOLENOID
RGFUEL DELIVERY14a-7
FUEL LINES (Continued)
ProCarManuals.com
(6) Using special tool VM.1055 (Fig. 7), torque
injection pump sprocket retaining nut to 88.3N´m.
(7) Connect fuel pressure solenoid electrical con-
nector (Fig. 11).
(8) Connect fuel supply and return lines at injec-
tion pump (Fig. 11).
(9) Install generator (Fig. 11)(Refer to 8 - ELEC-
TRICAL/CHARGING/GENERATOR - INSTALLA-
TION).(10) Install outer timing belt cover (Refer to 9 -
ENGINE/VALVE TIMING/TIMING BELT / CHAIN
COVER(S) - INSTALLATION).
(11) Install right engine mount assembly.
(12) Install accessory drive belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
INSTALLATION).
(13) Install power steering belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
INSTALLATION).
(14) Install air cleaner housing assembly.
(15) Install engine cover (Refer to 9 - ENGINE -
INSTALLATION).
(16) Connect negative battery cable.
WATER IN FUEL SENSOR
DESCRIPTION
The WIF sensor is located in the bowl assembly of
the fuel filter/water separator.
OPERATION
The sensor sends an input to the Engine Control
Module (ECM) when it senses water in the fuel filter/
water separator. As the water level in the filter/sep-
arator increases, the resistance across the WIF
sensor decreases. This decrease in resistance is sent
as a signal to the ECM and compared to a high
water standard value. Once the value reaches 30 to
40 kilohms, the ECM will activate the water-in-fuel
warning lamp through CCD bus circuits. This all
takes place when the ignition key is initially put in
the ON position. The ECM continues to monitor the
input at the end of the intake manifold air heater
post-heat cycle.
Fig. 11 FUEL INJECTION PUMP LOCATION
1 - CYLINDER HEAD COVER/INTAKE MANIFOLD
2 - INJECTION PUMP
3 - FUEL PRESSURE SOLENOID
4 - ACCESSORY MOUNTING BRACKET
5 - GENERATOR
14a - 10 FUEL DELIVERYRG
FUEL INJECTION PUMP (Continued)
ProCarManuals.com
MASS AIR FLOW (MAF)
SENSOR
DESCRIPTION
The Mass Air Flow (MAF) Sensor is mounted
inline in the air intake between the air filter and the
turbocharger (Fig. 8).
OPERATION
The ECM uses the mass air flow (MAF) sensor to
measure air density. The MAF sensor contains a
ceramic element. A signal voltage is provided to the
element. As engine speed increases, airflow across
the ceramic element increases. Changes in air flow
and air density cause the temperature of the ceramic
element to fluxuate. The ceramic element changes
resistance respectively to changes in temperature.
The change in resistance varies the signal voltage
output to the ECM. The diesel power relay supplies
battery power the to MAF sensor. Ground is providedby the ECM. The MAF sensor signal is provided by
the ECM.
REMOVAL
(1) Disconnect negative battery cable.
(2) Disconnect MAF sensor electrical connector
(Fig. 9).
(3) Loosen MAF sensor retaining clamps (Fig. 9).
(4) Remove MAF sensor from airduct (Fig. 9).
INSTALLATION
(1) Install MAF sensor in airduct (Fig. 9).
(2) Tighten retaining clamps (Fig. 9).
(3) Connect MAF sensor electrical connector (Fig.
9).
(4) Connect negative battery cable.
Fig. 8 MASS AIR FLOW (MAF) SENSOR
Fig. 9 MASS AIR FLOW (MAF) SENSOR LOCATION
1 - MAF SENSOR ELECTRICAL CONNECTOR
2 - RETAINING CLAMPS
3 - MASS AIR FLOW (MAF) SENSOR
4 - AIR CLEANER HOUSING
14a - 16 FUEL INJECTIONRG
ProCarManuals.com
31TH AUTOMATIC TRANSAXLE
TABLE OF CONTENTS
page page
31TH AUTOMATIC TRANSAXLE
DESCRIPTION.........................22
OPERATION...........................24
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - PRELIMINARY
DIAGNOSIS..........................24
DIAGNOSIS AND TESTING - ROAD TEST . . . 31
DIAGNOSIS AND TESTING - HYDRAULIC
PRESSURE TESTS....................32
DIAGNOSIS AND TESTING - TORQUE
CONVERTER HOUSING FLUID LEAKAGE . . . 35
DIAGNOSIS AND TESTING - CLUTCH AND
SERVO AIR PRESSURE TESTS..........35
STANDARD PROCEDURE - ALUMINUM
THREAD REPAIR......................37
REMOVAL.............................37
DISASSEMBLY.........................40
ASSEMBLY............................51
INSTALLATION.........................61
SCHEMATICS AND DIAGRAMS
31TH TRANSAXLE HYDRAULIC
SCHEMATICS........................64
SPECIFICATIONS
31TH AUTOMATIC TRANSAXLE..........72
SPECIAL TOOLS
31TH AUTOMATIC TRANSAXLE..........75
ACCUMULATOR
DESCRIPTION.........................79
OPERATION...........................79
BANDS
DESCRIPTION
KICKDOWN (FRONT) BAND.............80
OPERATION
LOW/REVERSE (REAR) BAND...........80
ADJUSTMENTS
ADJUSTMENT - FRONT BAND...........80
ADJUSTMENTS - REAR BAND...........80
CLUTCH - FRONT
DESCRIPTION.........................82
OPERATION...........................82
DISASSEMBLY.........................82
ASSEMBLY............................84
CLUTCH - REAR
DESCRIPTION.........................86
OPERATION...........................86
DISASSEMBLY.........................87
ASSEMBLY............................89
FINAL DRIVE
DISASSEMBLY.........................91
ASSEMBLY............................94ADJUSTMENTS
ADJUSTMENT - DIFFERENTIAL BEARING . . 97
FLUID
STANDARD PROCEDURE
STANDARD PROCEDURE - FLUID LEVEL
AND CONDITION CHECK...............99
STANDARD PROCEDURE - FLUID AND
FILTER CHANGE......................99
GEAR SHIFT CABLE
REMOVAL............................101
INSTALLATION........................102
ADJUSTMENTS
GEARSHIFT CABLE ADJUSTMENT.......104
GOVERNOR
DESCRIPTION........................104
OPERATION..........................104
CLEANING...........................104
INSPECTION.........................104
OIL PUMP
DESCRIPTION........................105
OPERATION..........................105
STANDARD PROCEDURE - OIL PUMP
VOLUME CHECK.....................105
DISASSEMBLY........................106
CLEANING...........................106
INSPECTION.........................106
ASSEMBLY...........................107
PARK/NEUTRAL POSITION SWITCH
DIAGNOSIS AND TESTING - PARK/NEUTRAL
POSITION SWITCH...................107
REMOVAL............................107
INSTALLATION........................107
PLANETARY GEARTRAIN
DISASSEMBLY........................108
ASSEMBLY...........................109
SEAL - OIL PUMP
REMOVAL............................110
INSTALLATION........................110
SERVO - KICKDOWN
DESCRIPTION........................111
OPERATION..........................111
DISASSEMBLY........................111
CLEANING...........................112
INSPECTION..........................113
ASSEMBLY...........................113
SERVO - LOW/REVERSE
DESCRIPTION........................113
OPERATION..........................113
DISASSEMBLY........................114
CLEANING...........................114
RS31TH AUTOMATIC TRANSAXLE21-21
ProCarManuals.com
CONDITION POSSIBLE CAUSES CORRECTION
BUZZING NOISE 1. Fluid Level Low 1. Add fluid and check for leaks.
2. Shift Cable Misassembled. 2. Route cable away from engine and bell
housing.
3. Valve Body Misassembled. 3. Remove, disassemble, inspect valve
body. Reassemble correctly if necessary.
Replace assembly if valves or springs are
damaged. Check for loose bolts or screws.
4. Pump Passages Leaking 4. Check pump for porous casting, scores
on mating surfaces and excess rotor
clearance. Repair as required. Loose pump
bolts.
5. Cooling System Cooler Plugged. 5. Flow check cooler circuit. Repair as
needed.
6.Overrunning Clutch Damaged. 6. Replace clutch.
SLIPS IN REVERSE ONLY 1. Fluid Level Low. 1. Add fluid and check for leaks.
2. Gearshift Linkage Misadjusted. 2. Adjust linkage.
3. Rear Band Misadjusted. 3. Adjust band.
4. Rear Band Worn. 4. Replace as required.
5. Hydraulic Pressure Too Low. 5. Perform hydraulic pressure tests to
determine cause.
6. Rear Servo Leaking. 6. Air pressure check clutch-servo operation
and repair as required.
7. Band Linkage Binding. 7. Inspect and repair as required.
SLIPS IN FORWARD
DRIVE RANGES1. Fluid Level Low. 1. Add fluid and check for leaks.
2. Fluid Foaming. 2. Check for high oil level, bad pump
gasket or seals, dirt between pump halves
and loose pump bolts. Replace pump if
necessary.
3. Throttle Linkage Misadjusted. 3. Adjust linkage.
4. Gearshift Linkage Misadjusted. 4. Adjust linkage.
5. Rear Clutch Worn. 5. Inspect and replace as needed.
6. Low Hydraulic Pressure Due to
Worn Pump, Incorrect Control
Pressure Adjustments, Valve Body
Warpage or Malfunction, Sticking
Governor, Leaking Seal Rings,
Clutch Seals Leaking, Servo Leaks,
Clogged Filter or Cooler Lines6. Perform hydraulic and air pressure tests
to determine cause.
7. Rear Clutch Malfunction, Leaking
Seals or Worn Plates.7. Air pressure check clutch-servo operation
and repair as required.
8. Overrunning Clutch Worn, Not
Holding (Slips in 1 Only).8. Replace Clutch.
SLIPS IN LOW GEAR9D9
ONLY, BUT NOT IN 1
POSITIONOverrunning Clutch Faulty. Replace overrunning clutch.
RS31TH AUTOMATIC TRANSAXLE21-29
31TH AUTOMATIC TRANSAXLE (Continued)
ProCarManuals.com
coating carefully. Do not reuse either part if the coat-
ing is damaged.
Inspect the governor weight spring for distortion.
Replace the spring, if distorted, collapsed, or broken.
Clean the filter in solvent and dry it with compressed
air. Replace the filter, if damaged. Inspect the park
gear for chipped or worn gear teeth or damaged ring
grooves. Replace the gear, if damaged.
Check the teeth on the park gear for wear or dam-
age. Replace the gear if necessary. Inspect the metal
seal rings on the park gear hub. Replace the rings
only if severely worn, or broken.
OIL PUMP
DESCRIPTION
The oil pump is located in the pump housing inside
the bell housing of the transmission case. The oil
pump consists of an inner and outer gear, a housing,
and a cover that also serves as the reaction shaft
support (Fig. 182).
OPERATION
As the torque converter rotates, the converter hub
rotates the inner and outer gears. As the gears
rotate, the clearance between the gear teeth
increases in the crescent area, and creates a suction
at the inlet side of the pump. This suction drawsfluid through the pump inlet from the oil pan. As the
clearance between the gear teeth in the crescent area
decreases, it forces pressurized fluid into the pump
outlet and to the valve body.
STANDARD PROCEDURE - OIL PUMP VOLUME
CHECK
Measuring the oil pump output volume will deter-
mine if sufficient oil flow to the transmission oil
cooler exists, and whether or not an internal trans-
mission failure is present.
Verify that the transmission fluid is at the proper
level. Refer to the Fluid Level Check procedure in
this section. If necessary, fill the transmission to the
proper level with MopartATF +4, type 9602, Auto-
matic Transmission Fluid.
(1) Using hose cutters or a suitable blade, cut the
To coolerline off flush with the cooler inlet fitting
and place a collecting container under the open line.
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.
(2) Run the engineat curb idle speed, with the
shift selector in neutral.
(3) If one quart of transmission fluid is collected in
the container in 20 seconds or less, oil pump flow vol-
ume is within acceptable limits. If fluid flow is inter-
Fig. 182 Oil Pump Assembly
1 - REACTION SHAFT SUPPORT
2 - INNER GEAR
3 - PUMP BODY4 - PUMP BUSHING
5 - OUTER GEAR
RS31TH AUTOMATIC TRANSAXLE21 - 105
GOVERNOR (Continued)
ProCarManuals.com
41TE AUTOMATIC TRANSAXLE
TABLE OF CONTENTS
page page
41TE AUTOMATIC TRANSAXLE
DESCRIPTION........................162
OPERATION..........................164
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - 41TE
TRANSAXLE GENERAL DIAGNOSIS......164
DIAGNOSIS AND TESTING - ROAD TEST . . 165
DIAGNOSIS AND TESTING - HYDRAULIC
PRESSURE TESTS...................165
DIAGNOSIS AND TESTING - CLUTCH AIR
PRESSURE TESTS...................168
DIAGNOSIS AND TESTING - TORQUE
CONVERTER HOUSING FLUID LEAKAGE . . 168
REMOVAL............................169
DISASSEMBLY........................171
ASSEMBLY...........................190
INSTALLATION........................213
SCHEMATICS AND DIAGRAMS
41TE TRANSAXLE HYDRAULIC
SCHEMATICS.......................216
SPECIFICATIONS - 41TE TRANSAXLE......228
SPECIAL TOOLS
41TE AUTOMATIC TRANSAXLE.........230
ACCUMULATOR
DESCRIPTION........................236
OPERATION..........................236
AUTOSTICK SWITCH
DESCRIPTION........................237
OPERATION..........................237
DRIVING CLUTCHES
DESCRIPTION........................237
OPERATION..........................238
FINAL DRIVE
DISASSEMBLY........................238
ASSEMBLY...........................243
ADJUSTMENTS
ADJUSTMENT - DIFFERENTIAL BEARING
PRELOAD..........................246
FLUID
STANDARD PROCEDURE
FLUID LEVEL AND CONDITION CHECK . . . 249
STANDARD PROCEDURE - FLUID AND
FILTER SERVICE.....................250
GEAR SHIFT CABLE
REMOVAL............................251
INSTALLATION........................253
ADJUSTMENTS
GEARSHIFT CABLE ADJUSTMENT.......254
HOLDING CLUTCHES
DESCRIPTION........................255OPERATION..........................255
INPUT CLUTCH ASSEMBLY
DISASSEMBLY........................255
ASSEMBLY...........................263
OIL PUMP
DESCRIPTION........................272
OPERATION..........................272
STANDARD PROCEDURE - OIL PUMP
VOLUME CHECK.....................272
DISASSEMBLY........................273
ASSEMBLY...........................274
PLANETARY GEARTRAIN
DESCRIPTION........................274
OPERATION..........................274
SEAL - OIL PUMP
REMOVAL............................275
INSTALLATION........................275
SHIFT INTERLOCK SOLENOID
DESCRIPTION........................275
OPERATION..........................276
DIAGNOSIS AND TESTING - BRAKE/
TRANSMISSION SHIFT INTERLOCK
SOLENOID..........................277
REMOVAL............................277
INSTALLATION........................278
SOLENOID/PRESSURE SWITCH ASSY
DESCRIPTION........................279
OPERATION..........................280
REMOVAL............................280
INSTALLATION........................281
SPEED SENSOR - INPUT
DESCRIPTION........................281
OPERATION..........................282
REMOVAL............................282
INSTALLATION........................283
SPEED SENSOR - OUTPUT
DESCRIPTION........................283
OPERATION..........................283
REMOVAL............................284
INSTALLATION........................284
TORQUE CONVERTER
DESCRIPTION........................285
OPERATION..........................289
REMOVAL............................290
INSTALLATION........................290
TRANSMISSION CONTROL RELAY
DESCRIPTION........................291
OPERATION..........................291
TRANSMISSION RANGE SENSOR
DESCRIPTION........................291
RS41TE AUTOMATIC TRANSAXLE21 - 161
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