2002 JEEP GRAND CHEROKEE manual transmission

CONDITION POSSIBLE CAUSES CORRECTION
BUZZING NOISE 1. Fluid Level Low 1. Add fluid and check for leaks.
2. Shift Cable Mis-assembled. 2. Route cable away from engine and bell
housing.
3. Valve Body Mis-assembled. 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
ONLY1. Fluid Level Low. 1. Add fluid and check for leaks.
2. Gearshift Linkage Mis-adjusted. 2. Adjust linkage.
3. Rear Band Mis-adjusted. 3. Adjust band.
4. Rear Band Worn. 4. Replace as required.
5. Overdrive Direct Clutch Worn. 5. Disassemble overdrive. Repair as needed.
6. Hydraulic Pressure Too Low. 6. Perform hydraulic pressure tests to determine
cause.
7. Rear Servo Leaking. 7. Air pressure check clutch-servo operation and
repair as required.
8. Band Linkage Binding. 8. 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 Mis-adjusted. 3. Adjust linkage.
4. Gearshift Linkage Mis-adjusted. 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,
Leaking Seal Rings, Clutch Seals
Leaking, Servo Leaks, Clogged
Filter or Cooler Lines.6. 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 GEAR
9D9ONLY, BUT NOT
IN MANUAL 1
POSITIONOverrunning Clutch Faulty. Replace overrunning clutch.
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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.
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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.
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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
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(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
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(32) Install valve body as follows:
(a) Align and carefully insert park rod into pawl.
Rod will make click noise as it enters pawl. Move
rod slightly to check engagement.
(b) Align and seat valve body on case. Be sure
manual lever shaft and overdrive connector are
fully seated in case. Also be sure valve body wiring
is not pinched or kinked.
(c) Install and start all valve body attaching
bolts by hand. Then tighten bolts evenly, in a diag-
onal pattern to 12 N´m (105 in. lbs.) torque. Do not
overtighten valve body bolts. This could result in
distortion and cross leakage after installation.
CAUTION: It is possible for the park rod to displace
into a cavity just above the pawl sprag during
installation. Make sure the rod is actually engaged
in the pawl and has not displaced into the cavity.
(33) Install new filter on valve body. Tighten filter
screws to 4 N´m (35 in. lbs.).
(34) Adjust front and rear bands.
(35) Install seal on park/neutral position switch.
Then install and tighten switch to 34 N´m (25 ft.
lbs.).
(36) Install magnet in oil pan. Magnet goes on
small protrusion at corner of pan.
(37) Position new oil pan gasket on case and
install oil pan. Tighten pan bolts to 17 N´m (13 ft.
lbs.).
(38) Install new valve body manual shaft seal in
case (Fig. 60). Lubricate seal lip and manual shaft
with petroleum jelly. Start seal over shaft and into
case. Seat seal with 15/16 inch, deep well socket.
(39) Install throttle valve and shift selector levers
on valve body manual lever shaft.INSTALLATION
(1) Check torque converter hub and hub drive
notches for sharp edges burrs, scratches, or nicks.
Polish the hub and notches with 320/400 grit paper
and crocus cloth if necessary. The hub must be
smooth to avoid damaging pump seal during installa-
tion.
(2) Lubricate oil pump seal lip with transmission
fluid.
(3) Align converter and oil pump.
(4) Carefully insert converter in oil pump. Then
rotate converter back and forth until fully seated in
pump gears.
(5) Check converter seating with steel scale and
straightedge (Fig. 61). Surface of converter lugs
should be 1/2 in. to rear of straightedge when con-
verter is fully seated.
(6) Temporarily secure converter with C-clamp.
(7) Position transmission on jack and secure it
with chains.
(8) Check condition of converter driveplate.
Replace the plate if cracked, distorted or damaged.
Also be sure transmission dowel pins are seated in
engine block and protrude far enough to hold trans-
mission in alignment.
(9) Apply a light coating of MopartHigh Temp
grease to the torque converter hub pocket in the rear
of the crankshaft
(10) Raise transmission and align converter with
drive plate and converter housing with engine block.
Fig. 60 Installing Manual Lever Shaft Seal
1 - 15/1688SOCKET
2 - SEAL
Fig. 61 Checking Torque Converter Seating - Typical
1 - SCALE
2 - STRAIGHTEDGE
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HYDRAULIC FLOW IN MANUAL LOW (1)
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AUTOMATIC TRANSMISSION - 42RE (Continued)

HYDRAULIC FLOW IN MANUAL SECOND (2)
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