2002 JEEP GRAND CHEROKEE Removing a transmission

(5) With a wiping cloth, clean the gasket sealing
surface of oil and grime.
INSTALLATION
(1) Lightly lubricate oil filter gasket with engine
oil.
(2) Thread filter onto adapter nipple. When gasket
makes contact with sealing surface, (Fig. 94)hand
tighten filter one full turn, do not over tighten.
(3) Add oil, verify crankcase oil level and start
engine. Inspect for oil leaks.
OIL PAN
DESCRIPTION
The engine oil pan is made of laminated steel and
has a single plane sealing surface. The sandwich
style oil pan gasket has an integrated windage tray
and steel carrier. The sealing area of the gasket is
molded with rubber and is designed to be reused as
long as the gasket is not cut, torn or ripped.
REMOVAL
(1) Disconnect negative cable from battery.
(2) Raise vehicle on hoist.
(3) Remove structural cover (Refer to 9 - ENGINE/
ENGINE BLOCK/STRUCTURAL COVER - REMOV-
AL).
(4) Remove exhaust system Y-pipe.
(5) Remove starter (Refer to 8 - ELECTRICAL/
STARTING/STARTER MOTOR - REMOVAL).
(6) Drain engine oil.
(7) Un-clip transmission lines from support on oil
pan stud. Move lines for oil pan clearance.
CAUTION: DO NOT pry on the oil pan gasket when
removing the oil pan, The oil pan gasket is mounted
to the cylinder block in three locations and will
remain attached to block when lowering oil pan.
Gasket can not be removed with oil pan.
(8) Remove oil pan bolts and oil pan.
(9) Remove oil pump pickup tube.
(10) Remove oil pan gasket.
CLEANING
(1) Clean oil pan in solvent and wipe dry with a
clean cloth.
(2) Clean the oil pan gasket surface.DO NOTuse
a grinder wheel or other abrasive tool to clean seal-
ing surface.
(3) Clean oil screen and tube thoroughly in clean
solvent.
INSPECTION
(1) Inspect oil drain plug and plug hole for
stripped or damaged threads. Repair as necessary.
(2) Inspect the oil pan mounting flange for bends
or distortion. Straighten flange, if necessary.
INSTALLATION
(1) Clean oil pan and all sealing surfaces. Inspect
oil pan gasket and replace as necessary.
(2) Install oil pan gasket.
Fig. 93 Oil Filter - 4.7L Engine
1 - ENGINE OIL FILTER
Fig. 94 Oil Filter Sealing SurfaceÐTypical
1 - SEALING SURFACE
2 - RUBBER GASKET
3 - OIL FILTER
9 - 132 ENGINE - 4.7LWJ
OIL FILTER (Continued)

KEY-IN IGNITION SWITCH
DESCRIPTION
The key-in ignition switch is concealed within and
integral to the ignition switch, which is mounted on
the steering column. The key-in ignition switch is
actuated by the ignition lock cylinder mechanism,
and is hard wired between a body ground and the
Body Control Module (BCM) through the instrument
panel wire harness.
The key-in ignition switch cannot be adjusted or
repaired and, if faulty or damaged, the entire igni-
tion switch unit must be replaced,(Refer to 19 -
STEERING/COLUMN/LOCK CYLINDER HOUSING
- REMOVAL). For complete circuit diagrams, refer to
Body Control Modulein the Contents of Wiring
Diagrams.
OPERATION
The key-in ignition switch closes a path to ground
for the BCM when the ignition key is inserted in the
ignition lock cylinder, and opens the ground path
when the key is removed from the ignition lock cyl-
inder. The BCM monitors the key-in ignition switch
status through an internal pull-up, then sends the
proper switch status messages to other electronic
modules over the Programmable Communications
Interface (PCI) data bus network. The key-in ignition
switch status is also used by the BCM as an input
for chime warning system operation.
DIAGNOSIS AND TESTING
KEY-IN IGNITION SWITCH
For complete circuit diagrams, refer toBody Con-
trol Modulein the Contents of Wiring Diagrams.
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, REFER TO GROUP 8M - PASSIVE
RESTRAINT SYSTEMS BEFORE ATTEMPTING ANY
STEERING WHEEL, STEERING COLUMN, OR
INSTRUMENT PANEL COMPONENT DIAGNOSIS OR
SERVICE. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN ACCIDENTAL AIR-
BAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.(1) Disconnect and isolate the battery negative
cable. Disconnect the instrument panel wire harness
connector from the key-in ignition switch connector
receptacle on the ignition switch. Check for continu-
ity between the key-in ignition switch sense and
ground terminals of the key-in ignition switch con-
nector receptacle. There should be continuity with
the key inserted in the ignition lock cylinder, and no
continuity with the key removed from the ignition
lock cylinder. If OK, go to Step 2. If not OK, replace
the faulty ignition switch unit.
(2) Check for continuity between the ground cir-
cuit cavity of the instrument panel wire harness con-
nector for the key-in ignition switch and a good
ground. There should be continuity. If OK, go to Step
3. If not OK, repair the open ground circuit to ground
as required.
(3) Disconnect the gray 26-way instrument panel
wire harness connector from the Body Control Mod-
ule (BCM) connector receptacle. Check for continuity
between the key-in ignition switch sense circuit cav-
ity of the instrument panel wire harness connector
for the key-in ignition switch and a good ground.
There should be no continuity. If OK, go to Step 4. If
not OK, repair the shorted key-in ignition switch
sense circuit as required.
(4) Check for continuity between the key-in igni-
tion switch sense circuit cavities of the instrument
panel wire harness connector for the key-in ignition
switch and the gray 26-way instrument panel wire
harness connector for the BCM. There should be con-
tinuity. If OK, use a DRB scan tool and the proper
Diagnostic Procedures manual to test the BCM. If
not OK, repair the open key-in ignition switch sense
circuit as required.
LOCK CYLINDER
REMOVAL
The ignition key must be in the key cylinder for
cylinder removal. The key cylinder must be removed
first before removing ignition switch.
(1) Disconnect negative battery cable at battery.
(2) If equipped with an automatic transmission,
place shifter in PARK position.
(3) Rotate key to ON position.
19 - 14 COLUMNWJ

(4) A release tang is located on bottom of key cyl-
inder (Fig. 18).(5) Position a small screwdriver or pin punch into
tang access hole on bottom of steering column lower
cover (Fig. 19).
(6) Push the pin punch up while pulling key cylin-
der from steering column.
INSTALLATION
The ignition key must be in the key cylinder for
cylinder removal. The key cylinder must be removed
first before removing ignition switch.
(1) If equipped with an automatic transmission,
place shifter in PARK position.
(2) Position key cylinder into steering column as it
would normally be in the ON position.
(3) Press key cylinder into column until it snaps
into position.
(4) Check mechanical operation of switch.Auto-
matic Transmission:Be sure transmission lever is
locked in PARK position after key removal. If key is
difficult to rotate or is difficult to remove, the shift
lever-to-steering column cable may be out of adjust-
ment or defective. Refer to Transmission for proce-
dures.Manual Transmission:Be sure key cannot
be removed until release lever is operated. If key can
be removed, release lever mechanism may be defec-
tive. Release lever mechanism is not serviced sepa-
rately. If repair is necessary, the steering column
must be replaced,(Refer to 19 - STEERING/COL-
UMN - REMOVAL).
(5) Connect negative cable to battery.
(6) Check electrical operation of switch.
STEERING WHEEL
REMOVAL
For steering wheel removal procedure,(Refer to 8 -
ELECTRICAL/RESTRAINTS/CLOCKSPRING -
REMOVAL).
INSTALLATION
For steering wheel installation procedure,(Refer to
8 - ELECTRICAL/RESTRAINTS/CLOCKSPRING -
INSTALLATION).
Fig. 18 Key Cylinder Release Tang
1 - KEY CYLINDER
2 - RELEASE TANG
Fig. 19 Key Cylinder and Cover Removal
1 - LOWER COVER
2 - ACCESS HOLE
3 - PIN PUNCH
4 - COVER SCREWS (3)
WJCOLUMN 19 - 15
LOCK CYLINDER (Continued)

TEST CONDITION INDICATION
Governor pressure low at
all mph figuresFaulty governor pressure
solenoid, transmission
control module, or
governor pressure
sensor
Lubrication pressure low
at all throttle positionsClogged fluid cooler or
lines, seal rings leaking,
worn pump bushings,
pump, clutch retainer, or
clogged filter.
Line pressure high Output shaft plugged,
sticky regulator valve
Line pressure low Sticky regulator valve,
clogged filter, worn pump
DIAGNOSIS AND TESTING - AIR CHECKING
TRANSMISSION CLUTCH AND BAND
OPERATION
Air-pressure testing can be used to check transmis-
sion front/rear clutch and band operation. The test
can be conducted with the transmission either in the
vehicle or on the work bench, as a final check, after
overhaul.
Air-pressure testing requires that the oil pan and
valve body be removed from the transmission. The
servo and clutch apply passages are shown (Fig. 10).
Front Clutch Air Test
Place one or two fingers on the clutch housing and
apply air pressure through front clutch apply pas-
sage. Piston movement can be felt and a soft thump
heard as the clutch applies.
Rear Clutch Air Test
Place one or two fingers on the clutch housing and
apply air pressure through rear clutch apply passage.
Piston movement can be felt and a soft thump heard
as the clutch applies.
Front Servo Apply Air Test
Apply air pressure to the front servo apply pas-
sage. The servo rod should extend and cause the
band to tighten around the drum. Spring pressure
should release the servo when air pressure is
removed.
Rear Servo Air Test
Apply air pressure to the rear servo apply passage.
The servo rod should extend and cause the band to
tighten around the drum. Spring pressure should
release the servo when air pressure is removed.
DIAGNOSIS AND TESTING - CONVERTER
HOUSING FLUID LEAK
When diagnosing converter housing fluid leaks,
two items must be established before repair.
(1) Verify that a leak condition actually exists.
(2) Determined the true source of the leak.
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.
Converter housing leaks have several potential
sources. Through careful observation, a leak source
can be identified before removing the transmission
for repair. Pump seal leaks tend to move along the
drive hub and onto the rear of the converter. Pump
body leaks follow the same path as a seal leak (Fig.
11). Pump vent or pump attaching bolt leaks are gen-
erally deposited on the inside of the converter hous-
ing and not on the converter itself (Fig. 11). Pump
o-ring or gasket leaks usually travel down the inside
of the converter housing. Front band lever pin plug
Fig. 10 Air Pressure Test Passages
1 - REAR SERVO APPLY
2 - FRONT SERVO APPLY
3 - PUMP SUCTION
4 - FRONT CLUTCH APPLY
5 - FRONT SERVO RELEASE
6 - LINE PRESSURE TO ACCUMULATOR
7 - PUMP PRESSURE
8 - TO CONVERTER
9 - REAR CLUTCH APPLY
10 - FROM CONVERTER
11 - TO COOLER
WJAUTOMATIC TRANSMISSION - 42RE 21 - 15
AUTOMATIC TRANSMISSION - 42RE (Continued)

REMOVAL
The overdrive unit can be removed and serviced
separately. It is not necessary to remove the entire
transmission assembly to perform overdrive unit
repairs.
If only the overdrive unit requires service, refer to
Overdrive Removal for proper procedures.
CAUTION: The transmission and torque converter
must be removed as an assembly to avoid compo-
nent damage. The converter driveplate, pump bush-
ing, or oil seal can be damaged if the converter is
left attached to the driveplate during removal. Be
sure to remove the transmission and converter as
an assembly.
(1) Disconnect battery negative cable.
(2) Disconnect and lower or remove necessary
exhaust components.
(3) Disconnect fluid cooler lines at transmission.
(4) Remove starter motor. (Refer to 8 - ELECTRI-
CAL/STARTING/STARTER MOTOR - REMOVAL)
(5) Disconnect and remove crankshaft position sen-
sor. (Refer to 14 - FUEL SYSTEM/FUEL INJEC-
TION/CRANKSHAFT POSITION SENSOR -
REMOVAL) Retain sensor attaching bolts.
CAUTION: The crankshaft position sensor will be
damaged if the transmission is removed, or
installed, while the sensor is still bolted to the
engine block, or transmission (4.0L only). To avoid
damage, be sure to remove the sensor before
removing the transmission.
(6) Remove the bolts holding the bell housing
brace to the transmission.
(7) Remove nut holding the bell housing brace to
the engine to transmission bending brace.
(8) Remove the bell housing brace from the trans-
mission (Fig. 13).
(9) Remove the bolt holding the torque converter
cover to the transmission.
(10) Remove the torque converter cover from the
transmission.
(11) If transmission is being removed for overhaul,
remove transmission oil pan, drain fluid and reinstall
pan.
(12) Remove fill tube bracket bolts and pull tube
out of transmission. Retain fill tube seal. On4x4
models, it will also be necessary to remove bolt
attaching transfer case vent tube to converter hous-
ing.
(13) Rotate crankshaft in clockwise direction until
converter bolts are accessible. Then remove bolts one
at a time. Rotate crankshaft with socket wrench on
dampener bolt.(14) Mark propeller shaft and axle yokes for
assembly alignment. Then disconnect and remove
propeller shaft. On4x4models, remove both propel-
ler shafts.
(15) Disconnect wires from park/neutral position
switch and transmission solenoid.
(16) Disconnect gearshift cable from transmission
manual valve lever (Fig. 14).
Fig. 13 Bell Housing Brace and Converter Cover
1 - Transmission
2 - Torque Converter Cover
3 - Bellhousing Brace
Fig. 14 Transmission Shift Cable
1 - SHIFT CABLE
2 - MANUAL LEVER
3 - MANUAL LEVER
WJAUTOMATIC TRANSMISSION - 42RE 21 - 27
AUTOMATIC TRANSMISSION - 42RE (Continued)

(18) Squeeze front band together and remove band
strut (Fig. 27).
(19) Remove front band lever (Fig. 28).
(20) Remove front band lever shaft plug, if neces-
sary, from converter housing.
(21) Remove front band lever shaft.
(22) Remove front and rear clutch units as assem-
bly. Grasp input shaft, hold clutch units together and
remove them from case (Fig. 29).
(23) Lift front clutch off rear clutch (Fig. 30). Set
clutch units aside for overhaul.(24) Remove intermediate shaft thrust washer
from front end of shaft or from rear clutch hub (Fig.
31).
(25) Remove output shaft thrust plate from inter-
mediate shaft hub (Fig. 32).
(26) Slide front band off driving shell (Fig. 33) and
remove band from case.
Fig. 26 Removing Oil Pump And Reaction Shaft
Support Assembly
1 - OIL PUMP AND REACTION SHAFT SUPPORT ASSEMBLY
2 - SLIDE HAMMER TOOLS C-3752
Fig. 27 Removing Front Band Strut
1 - BAND LEVER
2 - BAND STRUT
3 - FRONT BAND
Fig. 28 Removing Front Band Lever
1 - FRONT BAND LEVER
Fig. 29 Removing Front/Rear Clutch Assemblies
1 - INPUT SHAFT
2 - FRONT CLUTCH
3 - REAR CLUTCH
WJAUTOMATIC TRANSMISSION - 42RE 21 - 31
AUTOMATIC TRANSMISSION - 42RE (Continued)

(27) Remove planetary geartrain as assembly (Fig.
34). Support geartrain with both hands during
removal. Do not allow machined surfaces on interme-
diate shaft or overdrive piston retainer to become
nicked or scratched.
(28) If overdrive unit is not to be serviced, install
Alignment Shaft 6227-2 into the overdrive unit to
prevent misalignment of the overdrive clutches dur-
ing service of main transmission components.
Fig. 30 Separating Front/Rear Clutch Assemblies
1 - FRONT CLUTCH
2 - REAR CLUTCH
Fig. 31 Removing Intermediate Shaft Thrust Washer
1 - INTERMEDIATE SHAFT THRUST WASHER
2 - INPUT SHAFT
3 - REAR CLUTCH RETAINER HUB
Fig. 32 Removing Intermediate Shaft Thrust Plate
1 - INTERMEDIATE SHAFT HUB
2 - INTERMEDIATE SHAFT THRUST PLATE
Fig. 33 Front Band Removal
1 - DRIVING SHELL
2 - FRONT BAND
21 - 32 AUTOMATIC TRANSMISSION - 42REWJ
AUTOMATIC TRANSMISSION - 42RE (Continued)

(29) Loosen rear band adjusting screw 4-5 turns.
(30) Remove low-reverse drum snap-ring (Fig. 35).(31) Remove low-reverse drum and reverse band.
(32) Remove overrunning clutch roller and spring
assembly as a unit (Fig. 36).
(33) Compress front servo rod guide about 1/8 inch
with Valve Spring Compressor C-3422-B (Fig. 37).
(34) Remove front servo rod guide snap-ring. Exer-
cise caution when removing snap-ring. Servo bore
can be scratched or nicked if care is not exercised.
(35) Remove compressor tools and remove front
servo rod guide, spring and servo piston.
Fig. 34 Removing Planetary Geartrain And
Intermediate Shaft Assembly
1 - PLANETARY GEARTRAIN AND INTERMEDIATE SHAFT
ASSEMBLY
Fig. 35 Removing Low-Reverse Drum Snap-Ring
1 - LOW-REVERSE DRUM
2 - HUB OF OVERDRIVE PISTON RETAINER
3 - LOW-REVERSE DRUM SNAP-RING
Fig. 36 Overrunning Clutch Assembly Removal
1 - OVERRUNNING CLUTCH CAM
2 - REAR BAND REACTION PIN
3 - OVERRUNNING CLUTCH ASSEMBLY
Fig. 37 Compressing Front Servo Rod Guide
1 - SPRING COMPRESSOR TOOL C-3422-B
2 - ROD GUIDE SNAP-RING
WJAUTOMATIC TRANSMISSION - 42RE 21 - 33
AUTOMATIC TRANSMISSION - 42RE (Continued)