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

CONDITION POSSIBLE CAUSES CORRECTION
NO START IN PARK
OR NEUTRAL1. Gearshift Linkage/Cable
Mis-adjusted.1. Adjust linkage/cable.
2. Neutral Sense Wire Open/Cut. 2. Check continuity with test lamp. Repair as
required.
3. Park/Neutral Switch, or
Transmission Range Sensor Faulty.3. Refer to service section for test and
replacement procedure.
4. Park/Neutral Switch, or
Transmission Range Sensor
Connection Faulty.4. Connectors spread open. Repair.
5. Valve Body Manual Lever
Assembly Bent/Worn/Broken.5. Inspect lever assembly and replace if damaged.
NO REVERSE (OR
SLIPS IN REVERSE)1. Direct Clutch Pack (front clutch)
Worn.1. Disassemble unit and rebuild clutch pack.
2. Rear Band Mis-adjusted. 2. Adjust band.
3. Front Clutch Malfunctioned/
Burned.3. Air-pressure test clutch operation. Remove and
rebuild if necessary.
4. Overdrive Thrust Bearing
Failure.4. Disassemble geartrain and replace bearings.
5. Direct Clutch Spring Collapsed/
Broken.5. Remove and disassemble unit. Check clutch
position and replace spring.
WJAUTOMATIC TRANSMISSION - 42RE 21 - 25
AUTOMATIC TRANSMISSION - 42RE (Continued)

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)

(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)

(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)

(10) Install thrust plate on intermediate shaft hub
(Fig. 47). Use petroleum jelly to hold thrust plate in
place.
(11) Check seal ring on rear clutch retainer hub
and seal rings on input shaft (Fig. 48). Also verify
that shaft seal rings are installed in sequence shown.
(12) Install rear clutch thrust washer (Fig. 49).
Use additional petroleum jelly to hold washer in
place if necessary.
(13) Align clutch discs in front clutch and install
front clutch on rear clutch (Fig. 50). Rotate front
clutch retainer back and forth until completely
seated on rear clutch retainer.
(14) Coat intermediate shaft thrust washer with
petroleum jelly. Then install washer in rear clutch
hub (Fig. 51). Use enough petroleum jelly to hold
washer in place. Be sure grooved side of washer faces
rearward (toward output shaft) as shown. Also note
that washer only fits one way in clutch hub. Note
thickness of this washer. It is a select fit part and is
used to control transmission end play.
Fig. 46 Installing Planetary Geartrain
1 - PLANETARY GEARTRAIN AND INTERMEDIATE SHAFT
ASSEMBLY
Fig. 47 Installing Intermediate Shaft Thrust Plate
1 - INTERMEDIATE SHAFT HUB
2 - INTERMEDIATE SHAFT THRUST PLATE
Fig. 48 Input Shaft Seal Ring Location
1 - INPUT SHAFT
2 - TEFLON SEAL RING
3 - PLASTIC SEAL RING
4 - REAR CLUTCH RETAINER
Fig. 49 Installing Rear Clutch Thrust Washer
1 - REAR CLUTCH RETAINER
2 - REAR CLUTCH THRUST WASHER (FIBER)
WJAUTOMATIC TRANSMISSION - 42RE 21 - 37
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)

ACCUMULATOR
DESCRIPTION
The accumulator (Fig. 62) is a hydraulic device
that has the sole purpose of cushioning the applica-
tion of a band or clutch. The accumulator consists of
a dual-land piston and a spring located in a bore in
the transmission case. The 3-4 accumulator is located
in a housing attached to the side of the valve body
(Fig. 63).
OPERATION
Both the accumulator and the 3-4 accumulator
function the same. Line pressure is directed to the
small end of the piston when the transmission is
placed into a DRIVE position (Fig. 64), bottoming it
against the accumulator plate. When the 1-2 upshift
occurs (Fig. 65), line pressure is directed to the large
end of the piston and then to the kickdown servo. As
the line pressure reaches the accumulator, the com-
bination of spring pressure and line pressure forces
the piston away from the accumulator plate. This
causes a balanced pressure situation, which results
in a cushioned band application. After the kickdown
servo has become immovable, line pressure will fin-
ish pushing the accumulator up into its bore. When
the large end of the accumulator piston is seated in
its bore, the band or clutch is fully applied.
NOTE: The accumulator is shown in the inverted
position for illustrative purposes.
INSPECTION
Inspect the accumulator piston and seal rings (Fig.
66). Replace the seal rings if worn or cut. Replace the
piston if chipped or cracked.
Check condition of the accumulator inner and
outer springs (Fig. 66). Replace the springs if the
coils are cracked, distorted or collapsed.
Fig. 62 Accumulator
1 - ACCUMULATOR PISTON
2 - PISTON SPRING
Fig. 63 3-4 Accumulator and Housing
1 - ACCUMULATOR PISTON
2 - 3-4 ACCUMULATOR HOUSING
3 - TEFLON SEALS
4 - PISTON SPRING
5 - COVER PLATE AND SCREWS
Fig. 64 Accumulator in DRIVE - FIRST Gear Position
1 - LINE PRESSURE
21 - 60 AUTOMATIC TRANSMISSION - 42REWJ

BANDS
DESCRIPTION
KICKDOWN (FRONT) BAND
The kickdown, or ªfrontº, band (Fig. 67) holds the
common sun gear of the planetary gear sets. The
front (kickdown) band is made of steel, and faced on
its inner circumference with a friction-type lining.
One end of the band is anchored to the transmissioncase, and the other is acted on with a pushing force
by a servo piston. The front band is a single-wrap
design (the band does not completely encompass/
wrap the drum that it holds).
LOW/REVERSE (REAR) BAND
The low/reverse band, or ªrearº, band (Fig. 68) is
similar in appearance and operation to the front
band. The rear band is slightly different in that it
does not use a link bar, but is acted directly on by
the apply lever. This is referred to as a double-wrap
band design (the drum is completely encompassed/
wrapped by the band). The double-wrap band pro-
vides a greater holding power in comparison to the
single-wrap design.
OPERATION
KICKDOWN (FRONT) BAND
The kickdown band holds the common sun gear of
the planetary gear sets by applying and holding the
front clutch retainer, which is splined to the sun gear
driving shell, and in turn splined directly to the sun
gear. The application of the band by the servo is typ-
ically done by an apply lever and link bar.
LOW/REVERSE (REAR) BAND
The rear band holds the rear planet carrier sta-
tionary by being mounted around and applied to the
low/reverse drum.
Fig. 65 Accumulator in SECOND Gear Position
1 - BOTTOM OF BORE
2 - LINE PRESSURE
3 - SHUTTLE VALVE
Fig. 66 Accumulator Components
1 - INNER SPRING
2 - ACCUMULATOR PISTON
3 - OUTER SPRING
4 - SEAL RINGS
Fig. 67 Front Band
1 - FRONT BAND
2 - TRANSMISSION HOUSING
WJAUTOMATIC TRANSMISSION - 42RE 21 - 61
BANDS (Continued)