2003 JEEP GRAND CHEROKEE Schematic

TRANSMISSION AND TRANSFER CASE
TABLE OF CONTENTS
page page
AUTOMATIC TRANSMISSION - 42RE..........1
AUTOMATIC TRANSMISSION - 545RFE......177TRANSFER CASE - NV242................280
TRANSFER CASE - NV247................315
AUTOMATIC TRANSMISSION - 42RE
TABLE OF CONTENTS
page page
AUTOMATIC TRANSMISSION - 42RE
DESCRIPTION..........................3
OPERATION............................5
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - AUTOMATIC
TRANSMISSION......................11
DIAGNOSIS AND TESTING - PRELIMINARY . 11
DIAGNOSIS AND TESTING - ROAD
TESTING............................11
DIAGNOSIS AND TESTING - HYDRAULIC
PRESSURE TEST.....................12
DIAGNOSIS AND TESTING - AIR CHECKING
TRANSMISSION CLUTCH AND BAND
OPERATION.........................15
DIAGNOSIS AND TESTING - CONVERTER
HOUSING FLUID LEAK.................15
DIAGNOSIS AND TESTING - DIAGNOSIS
CHARTS............................16
STANDARD PROCEDURE - ALUMINUM
THREAD REPAIR......................26
REMOVAL.............................27
DISASSEMBLY.........................29
CLEANING............................34
INSPECTION..........................34
ASSEMBLY............................34
INSTALLATION.........................41
SCHEMATICS AND DIAGRAMS
HYDRAULIC SCHEMATICS..............43
SPECIFICATIONS
TRANSMISSION......................55
SPECIAL TOOLS
RE TRANSMISSIONS..................57
ACCUMULATOR
DESCRIPTION.........................60
OPERATION...........................60
INSPECTION..........................60BANDS
DESCRIPTION.........................61
OPERATION...........................61
ADJUSTMENTS
ADJUSTMENT - BANDS................62
BRAKE TRANSMISSION SHIFT INTERLOCK
MECHANISM
DESCRIPTION.........................63
OPERATION...........................63
DIAGNOSIS AND TESTING - BRAKE
TRANSMISSION SHIFT INTERLOCK.......63
ADJUSTMENTS - BRAKE TRANSMISSION
SHIFT INTERLOCK....................64
ELECTRONIC GOVERNOR
DESCRIPTION.........................65
OPERATION...........................65
REMOVAL.............................67
INSTALLATION.........................67
EXTENSION HOUSING BUSHING
REMOVAL.............................68
INSTALLATION.........................68
EXTENSION HOUSING SEAL
REMOVAL.............................69
INSTALLATION.........................69
FLUID AND FILTER
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - EFFECTS OF
INCORRECT FLUID LEVEL..............69
DIAGNOSIS AND TESTING - CAUSES OF
BURNT FLUID........................69
DIAGNOSIS AND TESTING - FLUID
CONTAMINATION.....................70
STANDARD PROCEDURE
STANDARD PROCEDURE - FLUID LEVEL
CHECK.............................70
WJTRANSMISSION AND TRANSFER CASE 21 - 1

leaks are generally deposited on the housing and not
on the converter.
TORQUE CONVERTER LEAK POINTS
Possible sources of converter leaks are:
(1) Leaks at the weld joint around the outside
diameter weld (Fig. 12).
(2) Leaks at the converter hub weld (Fig. 12).
CONVERTER HOUSING AREA LEAK CORRECTION
(1) Remove converter.
(2) Tighten front band adjusting screw until band
is tight around front clutch retainer. This prevents
front/rear clutches from coming out when oil pump is
removed.
(3) Remove oil pump and remove pump seal.
Inspect pump housing drainback and vent holes for
obstructions. Clear holes with solvent and wire.
(4) Inspect pump bushing and converter hub. If
bushing is scored, replace it. If converter hub is
scored, either polish it with crocus cloth or replace
converter.(5) Install new pump seal, O-ring, and gasket.
Replace oil pump if cracked, porous or damaged in
any way. Be sure to loosen the front band before
installing the oil pump, damage to the oil pump seal
may occur if the band is still tightened to the front
clutch retainer.
(6) Loosen kickdown lever pin access plug three
turns. Apply LoctiteŸ 592, or PermatextNo.2to
plug threads and tighten plug to 17 N´m (150 in. lbs.)
torque.
(7) Adjust front band.
(8) Lubricate pump seal and converter hub with
transmission fluid or petroleum jelly and install con-
verter.
(9) Install transmission and converter housing
dust shield.
(10) Lower vehicle.
DIAGNOSIS AND TESTING - DIAGNOSIS
CHARTS
The diagnosis charts provide additional reference
when diagnosing a transmission fault. The charts
provide general information on a variety of transmis-
sion, overdrive unit and converter clutch fault condi-
tions.
The hydraulic flow charts in the Schematics and
Diagrams section of this group, outline fluid flow and
hydraulic circuitry. Circuit operation is provided for
PARK, NEUTRAL, FIRST, SECOND, THIRD,
FOURTH, MANUAL FIRST, MANUAL SECOND,
and REVERSE gear ranges. Normal working pres-
sures are also supplied for each of the gear ranges.
Fig. 11 Converter Housing Leak Paths
1 - PUMP SEAL
2 - PUMP VENT
3 - PUMP BOLT
4 - PUMP GASKET
5 - CONVERTER HOUSING
6 - CONVERTER
7 - REAR MAIN SEAL LEAK
Fig. 12 Converter Leak Points - Typical
1 - OUTSIDE DIAMETER WELD
2 - TORQUE CONVERTER HUB WELD
3 - STARTER RING GEAR
4 - LUG
21 - 16 AUTOMATIC TRANSMISSION - 42REWJ
AUTOMATIC TRANSMISSION - 42RE (Continued)

SCHEMATICS AND DIAGRAMS
HYDRAULIC SCHEMATICS
HYDRAULIC FLOW IN PARK
WJAUTOMATIC TRANSMISSION - 42RE 21 - 43
AUTOMATIC TRANSMISSION - 42RE (Continued)

OPERATION
NOTE: Refer to the Hydraulic Schematics for a
visual aid in determining valve location, operation
and design.
CHECK BALLS
CHECK BALL NUMBER DESCRIPTION
1 Allows either the manual valve to put line pressure on the 1-2 governor plug or
the KD Valve to put WOT line pressure on the 1-2 governor plug.
2 Allows either the manual valve to put line pressure on the 2-3 governor plug or
the KD Valve to put WOT line pressure on the 2-3 governor plug.
3 Allows either the Reverse circuit or the 3rd gear circuit to pressurize the front
clutch.
4 Allows either the Manual Low circuit from the Manual Valve or the Reverse
from the Manual Valve circuit to pressurize the rear servo.
5 Directs line pressure to the spring end of the 2-3 shift valve in either Manual
Low or Manual 2nd, forcing the downshift to 2nd gear regardless of governor
pressure.
6 Provides a by-pass around the front servo orifice so that the servo can release
quickly.
7 Provides a by-pass around the rear clutch orifice so that the clutch can release
quickly.
8 Directs reverse line pressure through an orifice to the throttle valve eliminating
the extra leakage and insuring that Reverse line pressure pressure will be
sufficient.
9 Provides a by-pass around the rear servo orifice so that the servo can release
quickly.
ECE (10) Allows the lockup clutch to used at WOT in 3rd gear by putting line pressure
from the 3-4 Timing Valve on the interlock area of the 2-3 shift valve, thereby
preventing a 3rd gear Lock-up to 2nd gear kickdown.
WJAUTOMATIC TRANSMISSION - 42RE 21 - 139
VALVE BODY (Continued)

AUTOMATIC TRANSMISSION - 545RFE
TABLE OF CONTENTS
page page
AUTOMATIC TRANSMISSION - 545RFE
DESCRIPTION........................178
OPERATION..........................179
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - AUTOMATIC
TRANSMISSION.....................179
DIAGNOSIS AND TESTING - PRELIMINARY . 180
DIAGNOSIS AND TESTING - ROAD
TESTING...........................180
DIAGNOSIS AND TESTING - HYDRAULIC
PRESSURE TEST....................181
DIAGNOSIS AND TESTING - AIR CHECKING
TRANSMISSION CLUTCH OPERATION....182
DIAGNOSIS AND TESTING - CONVERTER
HOUSING FLUID LEAK................182
STANDARD PROCEDURE - ALUMINUM
THREAD REPAIR.....................183
REMOVAL............................183
DISASSEMBLY........................185
CLEANING...........................190
INSPECTION.........................190
ASSEMBLY...........................190
INSTALLATION........................197
SCHEMATICS AND DIAGRAMS
HYDRAULIC SCHEMATICS.............199
SPECIFICATIONS
TRANSMISSION.....................220
SPECIAL TOOLS
RFE TRANSMISSION.................221
4C RETAINER/BULKHEAD
DISASSEMBLY........................224
ASSEMBLY...........................224
ADAPTER HOUSING SEAL
REMOVAL............................225
INSTALLATION........................225
BRAKE TRANSMISSION SHIFT INTERLOCK
MECHANISM
DESCRIPTION........................226
OPERATION..........................226
DIAGNOSIS AND TESTING - BRAKE
TRANSMISSION SHIFT INTERLOCK......226
ADJUSTMENTS - BRAKE TRANSMISSION
SHIFT INTERLOCK...................227
FLUID AND FILTER
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - EFFECTS OF
INCORRECT FLUID LEVEL.............228
DIAGNOSIS AND TESTING - CAUSES OF
BURNT FLUID.......................228DIAGNOSIS AND TESTING - FLUID
CONTAMINATION....................228
STANDARD PROCEDURE
STANDARD PROCEDURE - FLUID LEVEL
CHECK............................229
STANDARD PROCEDURE - FLUID AND
FILTER REPLACEMENT...............230
STANDARD PROCEDURE - TRANSMISSION
FILL...............................230
GEARSHIFT CABLE
DIAGNOSIS AND TESTING - GEARSHIFT
CABLE.............................231
REMOVAL............................231
INSTALLATION........................231
ADJUSTMENTS - GEARSHIFT CABLE......232
HOLDING CLUTCHES
DESCRIPTION........................233
OPERATION..........................234
INPUT CLUTCH ASSEMBLY
DESCRIPTION........................235
OPERATION..........................235
DISASSEMBLY........................237
ASSEMBLY...........................238
INPUT SPEED SENSOR
DESCRIPTION........................244
OPERATION..........................244
REMOVAL............................244
INSTALLATION........................244
LINE PRESSURE (LP) SENSOR
DESCRIPTION........................245
OPERATION..........................245
REMOVAL............................245
INSTALLATION........................245
LOW/REVERSE CLUTCH
DISASSEMBLY........................246
CLEANING...........................247
INSPECTION.........................247
ASSEMBLY...........................247
OIL PUMP
DESCRIPTION........................248
OPERATION..........................248
STANDARD PROCEDURE - OIL PUMP
VOLUME CHECK.....................249
DISASSEMBLY........................250
CLEANING...........................252
INSPECTION.........................252
ASSEMBLY...........................253
OIL PUMP FRONT SEAL
REMOVAL............................253
WJAUTOMATIC TRANSMISSION - 545RFE 21 - 177

DIAGNOSIS AND TESTING - HYDRAULIC
PRESSURE TEST
An accurate tachometer and pressure test gauges
are required. Test Gauge C-3293-SP has a 300 psi
range and is used at all locations where pressures
exceed 100 psi.
Pressure Test Port Locations
Only two pressure ports are supplied on the trans-
mission case. The torque converter clutch apply and
release ports are located on the right side of the
transmission case (Fig. 2).
To determine the line pressure, there are two avail-
able methods. The DRBtscan tool can be used to
read line pressure from the line pressure sensor. The
second method is to install Line Pressure Adapter
8259 (Fig. 4) into the transmission case and then
install the pressure gauge and the original sensor
into the adapter. This will allow a comparison of the
DRBtreadings and the gauge reading to determe the
accuracy of the line pressure sensor. The DRBtline
pressure reading should match the gauge reading
within  10 psi.
In order to access any other pressure tap locations,
the transmission oil pan must be removed, the pres-
sure port plugs removed and Valve Body Pressure
Tap Adapter 8258-A (Fig. 5) installed. The extensions
supplied with Adapter 8258-A will allow the installa-
tion of pressure gauges to the valve body. Refer to
(Fig. 3) for correct pressure tap location identifica-
tion.
TEST PROCEDURE
All pressure readings should be taken with the
transmission fluid level full, transmission oil at the
normal operating temperature, and the engine at
1500 rpm. Check the transmission for proper opera-
tion in each gear position that is in question or if a
specific element is in question, check the pressure
readings in at least two gear positions that employ
that element. Refer to the Hydraulic Schematics at
the rear of this section to determine the correct pres-
sures for each element in a given gear position.
Fig. 2 Torque Converter Pressure Locations
1 - TCC RELEASE
2 - TO COOLER
3 - TCC APPLY
4 - FROM COOLER
5 - LINE PRESSURE SENSOR
Fig. 3 Pressure Tap Locations
Fig. 4 Line Pressure Adapter 8259
1 - LINE PRESSURE SENSOR PORT
2 - LINE PRESSURE SENSOR
3 - TOOL 8259
4 - PRESSURE TAP
WJAUTOMATIC TRANSMISSION - 545RFE 21 - 181
AUTOMATIC TRANSMISSION - 545RFE (Continued)

SCHEMATICS AND DIAGRAMS
HYDRAULIC SCHEMATICS
545RFE HYDRAULIC SCHEMATIC
WJAUTOMATIC TRANSMISSION - 545RFE 21 - 199
AUTOMATIC TRANSMISSION - 545RFE (Continued)

545RFE HYDRAULIC SCHEMATIC
21 - 200 AUTOMATIC TRANSMISSION - 545RFEWJ
AUTOMATIC TRANSMISSION - 545RFE (Continued)