Oil JEEP GRAND CHEROKEE 2002 WJ / 2.G Workshop Manual

CONDITION POSSIBLE CAUSES CORRECTION
OIL LEAKS. 1. Fluid Lines and Fittings
Loose/Leaks/Damaged.1. Tighten fittings. If leaks persist, replace fittings
and lines if necessary.
2. Fill Tube (where tube enters
case) Leaks/Damaged.2. Replace tube seal. Inspect tube for cracks in fill
tube.
3. Pressure Port Plug Loose
Loose/Damaged.3. Tighten to correct torque. Replace plug or
reseal if leak persists.
4. Pan Gasket Leaks. 4. Tighten pan screws (150 in. lbs.). If leaks
persist, replace gasket.
5. Valve Body Manual Lever Shaft
Seal Leaks/Worn.5. Replace shaft seal.
6. Rear Bearing Access Plate
Leaks.6. Replace gasket. Tighten screws.
7. Gasket Damaged or Bolts are
Loose.7. Replace bolts or gasket or tighten both.
8. Adapter/Extension Gasket
Damaged Leaks/Damaged.8. Replace gasket.
9. Park/Neutral Switch, or
Transmission Range Sensor
Leaks/Damaged.9. Replace switch and gasket.
10. Converter Housing Area Leaks. 10. Check for leaks at seal caused by worn seal
or burr on converter hub (cutting seal), worn
bushing, missing oil return, oil in front pump
housing or hole plugged. Check for leaks past
O-ring seal on pump or past pump-to-case bolts;
pump housing porous, oil coming out vent due to
overfill or leak past front band shaft access plug.
11. Pump Seal Leaks/Worn/
Damaged.11. Replace seal.
12. Torque Converter Weld
Leak/Cracked Hub.12. Replace converter.
13. Case Porosity Leaks. 13. Replace case.
NOISY OPERATION
IN FOURTH GEAR
ONLY1. Overdrive Clutch Discs, Plates
or Snap Rings Damaged.1. Remove unit and rebuild clutch pack.
2. Overdrive Piston or Planetary
Thrust Bearing Damaged.2. Remove and disassemble unit. Replace either
thrust bearing if damaged.
3. Output Shaft Bearings
Scored/Damaged.3. Remove and disassemble unit. Replace either
bearing if damaged.
4. Planetary Gears Worn/Chipped. 4. Remove and overhaul overdrive unit.
5. Overdrive Unit Overrunning
Clutch Rollers Worn/Scored.5. Remove and overhaul overdrive unit.
STANDARD PROCEDURE - ALUMINUM
THREAD REPAIR
Damaged or worn threads in the aluminum trans-
mission case and valve body can be repaired by the
use of Heli-CoilsŸ, or equivalent. This repair con-
sists of drilling out the worn-out damaged threads.
Then tap the hole with a special Heli-CoilŸ tap, or
equivalent, and installing a Heli-CoilŸ insert, orequivalent, into the hole. This brings the hole back to
its original thread size.
Heli-CoilŸ, or equivalent, tools and inserts are
readily available from most automotive parts suppli-
ers.
21 - 26 AUTOMATIC TRANSMISSION - 42REWJ
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)

(26) Remove bolts holding the upper transmission
bending braces to the torque converter housing and
the overdrive unit (Fig. 20).
(27) Remove all remaining converter housing bolts.
(28) Carefully work transmission and torque con-
verter assembly rearward off engine block dowels.
(29) Hold torque converter in place during trans-
mission removal.
(30) Lower transmission and remove assembly
from under the vehicle.
(31) To remove torque converter, carefully slide
torque converter out of the transmission.
DISASSEMBLY
(1) Clean transmission exterior with steam gun or
with solvent. Wear eye protection during cleaning
operations.
(2) Place transmission in a vertical position.(3) Measure input shaft end play as follows (Fig.
21).
(a) Attach Adapter 8266-6 to Handle 8266-8.
(b) Attach dial indicator C-3339 to Handle
8266-8.
(c) Install the assembled tool onto the input
shaft of the transmission and tighten the retaining
screw on Adapter 8266-6 to secure it to the input
shaft.
(d) Position the dial indicator plunger against a
flat spot on the oil pump and zero the dial indica-
tor.
(e) Move the input shaft in and out. Record the
maximum travel for assembly reference.
(4) Remove shift and throttle levers from valve
body manual lever shaft.
(5) Place transmission in horizontal position.
(6) Remove transmission oil pan and gasket.
(7) Remove filter from valve body (Fig. 22). Keep
filter screws separate from other valve body screws.
Filter screws are longer and should be kept with fil-
ter.
(8) Remove park/neutral position switch.
(9) Remove hex head bolts attaching valve body to
transmission case (Fig. 23). A total of 10 bolts are
used. Note different bolt lengths for assembly refer-
ence.
Fig. 19 Remove NV242 Transfer Case
1 - NV242 TRANSFER CASE
Fig. 20 Remove Upper Transmission Bending
Braces
1 - TRANSMISSION BENDING BRACES
Fig. 21 Checking Input Shaft End Play
1 - TOOL 8266-8
2 - TOOL 8266-6
3 - TOOL C-3339
WJAUTOMATIC TRANSMISSION - 42RE 21 - 29
AUTOMATIC TRANSMISSION - 42RE (Continued)

(10) Remove valve body assembly. Push valve body
harness connector out of case. Then work park rod
and valve body out of case (Fig. 24).
(11) Remove accumulator piston and inner and
outer springs (Fig. 25).
(12) Remove pump oil seal with suitable pry tool
or slide-hammer mounted screw.
(13) Loosen front band adjusting screw locknut 4-5
turns. Then tighten band adjusting screw until bandis tight around front clutch retainer. This prevents
front/rear clutches from coming out with pump and
possibly damaging clutch or pump components.
(14) Remove oil pump bolts.
(15) Thread bolts of Slide Hammer Tools C-3752
into threaded holes in pump body flange (Fig. 26).
(16) Bump slide hammer weights outward to
remove pump and reaction shaft support assembly
from case (Fig. 26).
(17) Loosen front band adjusting screw until band
is completely loose.
Fig. 22 Oil Filter Removal
1 - OIL FILTER
2 - VALVE BODY
3 - FILTER SCREWS (2)
Fig. 23 Valve Body Bolt Locations
1 - VALVE BODY BOLTS
2 - VALVE BODY BOLTS
Fig. 24 Valve Body Removal
1 - GOVERNOR PRESSURE SENSOR
2 - VALVE BODY
3 - PARK ROD
4 - ACCUMULATOR PISTON
5 - GOVERNOR PRESSURE SOLENOID
Fig. 25 Accumulator Piston And Springs
1 - ACCUMULATOR PISTON
2 - OUTER SPRING
3 - INNER SPRING
21 - 30 AUTOMATIC TRANSMISSION - 42REWJ
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)

(36) Compress rear servo spring retainer about
1/16 inch with Valve Spring Compressor C-3422-B
(Fig. 38).
(37) Remove rear servo spring retainer snap-ring.
Then remove compressor tools and remove rear servo
spring and piston.
(38) Inspect transmission components.
NOTE: To Service the overrunning clutch cam or
overdrive piston retainer, refer to the Overrunning
Clutch Cam service procedure in this section.
CLEANING
Clean the case in a solvent tank. Flush the case
bores and fluid passages thoroughly with solvent.
Dry the case and all fluid passages with compressed
air. Be sure all solvent is removed from the case and
that all fluid passages are clear.
NOTE: Do not use shop towels or rags to dry the
case (or any other transmission component) unless
they are made from lint-free materials. Lint will stick
to case surfaces and transmission components and
circulate throughout the transmission after assem-
bly. A sufficient quantity of lint can block fluid pas-
sages and interfere with valve body operation.Lubricate transmission parts with MopartATF +4,
type 9602, transmission fluid during overhaul and
assembly. Use petroleum jelly, MopartDoor Ease, or
Ru-GlydeŸ to prelubricate seals, O-rings, and thrust
washers. Petroleum jelly can also be used to hold
parts in place during reassembly.
INSPECTION
Inspect the case for cracks, porous spots, worn
bores, or damaged threads. Damaged threads can be
repaired with Helicoil thread inserts. However, the
case will have to be replaced if it exhibits any type of
damage or wear.
Lubricate the front band adjusting screw threads
with petroleum jelly and thread the screw part-way
into the case. Be sure the screw turns freely.
Inspect the transmission bushings during overhaul.
Bushing condition is important as worn, scored bush-
ings contribute to low pressures, clutch slip and
accelerated wear of other components. However, do
not replace bushings as a matter of course. Replace
bushings only when they are actually worn, or
scored.
Use recommended tools to replace bushings. The
tools are sized and designed to remove, install, and
seat bushings correctly. The bushing replacement
tools are included in Bushing Tool Set C-3887-B.
Pre-sized service bushings are available for
replacement purposes. Only the sun gear bushings
are not serviced.
The use of crocus cloth is permissible where neces-
sary, providing it is used carefully. When used on
shafts, or valves, use extreme care to avoid rounding
off sharp edges. Sharp edges are vital as they pre-
vent foreign matter from getting between the valve
and valve bore.
Do not reuse oil seals, gaskets, seal rings, or
O-rings during overhaul. Replace these parts as a
matter of course. Also do not reuse snap rings or
E-clips that are bent or distorted. Replace these parts
as well.
ASSEMBLY
Do not allow dirt, grease, or foreign material to
enter the case or transmission components during
assembly. Keep the transmission case and compo-
nents clean. Also make sure the tools and workbench
area used for assembly operations are equally clean.
Shop towels used for wiping off tools and hands
must be made fromlint freematerial. Lint will stick
to transmission parts and could interfere with valve
operation, or even restrict fluid passages.
Lubricate the transmission components with
Moparttransmission fluid during reassembly. Use
MopartDoor Ease, or Ru-GlydeŸ on seals and
O-rings to ease installation.
Fig. 38 Compressing Rear Servo Spring
1 - FRONT SERVO SNAP-RING
2 - REAR SERVO SNAP-RING
3 - SPECIAL TOOL
21 - 34 AUTOMATIC TRANSMISSION - 42REWJ
AUTOMATIC TRANSMISSION - 42RE (Continued)

Petroleum jelly can also be used to hold thrust
washers, thrust plates and gaskets in position during
assembly. However,do notuse chassis grease, bear-
ing grease, white grease, or similar lubricants on any
transmission part. These types of lubricants can
eventually block or restrict fluid passages and inter-
fere with valve operation. Use petroleum jelly only.
Do not force parts into place. The transmission
components and subassemblies are easily installed by
hand when properly aligned.
If a part seems extremely difficult to install, it is
either misaligned or incorrectly assembled. Also ver-
ify that thrust washers, thrust plates and seal rings
are correctly positioned before assembly. These parts
can interfere with proper assembly if mis-positioned.
The planetary geartrain, front/rear clutch assem-
blies and oil pump are all much easier to install
when the transmission case is upright.
(1) Install rear servo piston, spring and retainer
(Fig. 39). Install spring on top of servo piston and
install retainer on top of spring.
(2) Install front servo piston assembly, servo
spring and rod guide (Fig. 40).
(3) Compress front/rear servo springs with Valve
Spring Compressor C-3422-B and install each servo
snap-ring (Fig. 41).
(4) Lubricate clutch cam rollers with transmission
fluid.
(5) Install rear band in case (Fig. 42). Be sure twin
lugs on band are seated against reaction pin.
(6) Install low-reverse drum and check overrun-
ning clutch operation as follows:(a) Lubricate overrunning clutch race (on drum
hub) with transmission fluid.
(b) Guide drum through rear band.
(c) Tilt drum slightly and start race (on drum
hub) into overrunning clutch rollers.
(d) Press drum rearward and turn it in clock-
wise direction until drum seats in overrunning
clutch (Fig. 43).
Fig. 39 Rear Servo Components
1 - SERVO PISTON
2 - PISTON SPRING
3 - SNAP-RING
4 - RETAINER
5 - PISTON SEAL
Fig. 40 Front Servo Components
1 - PISTON SEAL RINGS
2 - SERVO PISTON
3 - SNAP-RING
4 - ROD GUIDE
5 - SPRING
6 - ROD
Fig. 41 Compressing Front/Rear Servo Springs
1 - SPRING COMPRESSOR TOOL C-3422-B
2 - ROD GUIDE SNAP-RING
WJAUTOMATIC TRANSMISSION - 42RE 21 - 35
AUTOMATIC TRANSMISSION - 42RE (Continued)

(15) Align drive teeth on rear clutch discs with
small screwdriver (Fig. 52). This makes installation
on front planetary easier.
(16) Raise front end of transmission upward as far
as possible and support case with wood blocks. Front/
rear clutch and oil pump assemblies are easier to
install if transmission is as close to upright position
as possible.
(17) Slide front band into case.
(18) Install front and rear clutch units as assembly
(Fig. 53). Align rear clutch with front annulus gear
and install assembly in driving shell. Be sure output
shaft thrust washer and thrust plate are not dis-
placed during installation.
(19) Carefully work assembled clutches back and
forth to engage and seat rear clutch discs on front
annulus gear. Also be sure front clutch drive lugs are
fully engaged in slots of driving shell after installa-
tion.
(20) Assemble front band strut.
(21) Install front band adjuster, strut and adjust-
ing screw (Fig. 54).
(22) Tighten band adjusting screw until band just
grips clutch retainer. Verify that front/rear clutches
are still seated before continuing.
Fig. 50 Assembling Front And Rear Clutch Units
1 - TURN FRONT CLUTCH BACK & FORTH UNTIL SEATED
2 - REAR CLUTCH ASSEMBLY
Fig. 51 Installing Intermediate Shaft Thrust Washer
1 - INTERMEDIATE SHAFT THRUST WASHER
2 - INPUT SHAFT
3 - REAR CLUTCH RETAINER HUB
Fig. 52 Aligning Rear Clutch Disc Lugs
1 - REAR CLUTCH DISCS
2 - USE SMALL SCREWDRIVER TO ALIGN CLUTCH DISC
TEETH
21 - 38 AUTOMATIC TRANSMISSION - 42REWJ
AUTOMATIC TRANSMISSION - 42RE (Continued)

(23) Check seal rings on reaction shaft support
hub. Verify that seal rings are hooked together and
that the thrust washer is properly positioned (Fig.
55). Use petroleum jelly to hold thrust washer in
place if necessary.(24) Lubricate oil pump body seal with petroleum
jelly. Lubricate pump shaft seal lip with petroleum
jelly.
(25) Thread two Pilot Stud Tools C-3288-B into
bolt holes in oil pump bore flange (Fig. 56).
(26) Align and install oil pump gasket (Fig. 56).
Fig. 53 Installing Front/Rear Clutch Assemblies
1 - INPUT SHAFT
2 - FRONT CLUTCH
3 - REAR CLUTCH
Fig. 54 Front Band Linkage Installation
1 - BAND LEVER
2 - BAND STRUT
3 - FRONT BAND
Fig. 55 Reaction Shaft Support Seal Rings And
Thrust Washer
1 - REACTION SHAFT SUPPORT HUB
2 - THRUST WASHER
3 - SEAL RINGS
Fig. 56 Installing Pilot Studs And Oil Pump Gasket
1 - OIL PUMP GASKET
2 - PILOT STUD TOOLS C-3288-B
WJAUTOMATIC TRANSMISSION - 42RE 21 - 39
AUTOMATIC TRANSMISSION - 42RE (Continued)

(27) Install oil pump (Fig. 57). Align and position
pump on pilot studs. Slide pump down studs and
work it into front clutch hub and case by hand. Then
install 2 or 3 pump bolts to hold pump in place.
(28) Remove pilot stud tools and install remaining
oil pump bolts. Tighten bolts alternately in diagonal
pattern to 20 N´m (15 ft. lbs.).
(29) Measure input shaft end play (Fig. 58).
NOTE: If end play is incorrect, transmission is
incorrectly assembled, or the intermediate shaft
thrust washer is incorrect. The intermediate shaft
thrust washer is selective.
(a) Attach Adapter 8266-6 to Handle 8266-8.
(b) Attach dial indicator C-3339 to Handle
8266-8.
(c) Install the assembled tool onto the input
shaft of the transmission and tighten the retaining
screw on Adapter 8266-6 to secure it to the input
shaft.
(d) Position the dial indicator plunger against a
flat spot on the oil pump and zero the dial indica-
tor.
(e) Move input shaft in and out and record read-
ing. End play should be 0.56-2.31 mm (0.022-0.091
in.). Adjust as necessary.
(30) Install accumulator piston and inner and
outer springs (Fig. 59).
(31) Verify that valve body solenoid harness is
secured in 3-4 accumulator housing cover plate.
Fig. 57 Installing Oil Pump
1 - OIL PUMP
2 - PILOT STUD TOOL
3 - PILOT STUD TOOL
Fig. 58 Checking Input Shaft End Play
1 - TOOL 8266-8
2 - TOOL 8266-6
3 - TOOL C-3339
Fig. 59 Accumulator Piston And Springs
1 - GOVERNOR PRESSURE SENSOR
2 - VALVE BODY
3 - PARK ROD
4 - ACCUMULATOR PISTON
5 - GOVERNOR PRESSURE SOLENOID
21 - 40 AUTOMATIC TRANSMISSION - 42REWJ
AUTOMATIC TRANSMISSION - 42RE (Continued)