1994 JEEP CHEROKEE front

TRANSMISSION COOLER SERVICE
Main Cooler
The transmission main cooler is located in the ra-
diator. The main cooler can be flushed when neces-
sary, however, the cooler is not a repairable
component. If the cooler is damaged, plugged, or
leaking, the radiator will have to be replaced.
Auxiliary Cooler
The auxiliary cooler is mounted in front of the ra-
diator at the driver side of the vehicle (Fig. 48). The
cooler can be flushed when necessary, while mounted
in the vehicle. The cooler can also be removed for ac-
cess, repair, or replacement as needed.
The main and auxiliary coolers should both be
flushed whenever a transmission or converter clutch
malfunction generates sludge, debris, or particles of
clutch friction material.
Cooler Service
The main cooler (and radiator) and the auxiliary
cooler can be removed for service or access to other
components. Auxiliary cooler removal requires that
the front bumper and radiator support be removed
for access to the cooler lines and attaching bracket.
REVERSE FLUSHING MAIN AND AUXILIARY
COOLERS AND COOLER LINES
Reverse flushing the cooler and lines will prevent
sludge and particles from flowing back into the
transmission after repair. The flushing procedure ap-
plies to standard (in-radiator) coolers and auxiliary
coolers equally.
Pressure equipment is preferred for reverse flush-
ing. However, reverse flushing can be performed us-
ing hand operated equipment as described in the
following procedure.
(1) Disconnect cooler lines at transmission and at
auxiliary cooler (Figs. 48 and 49).
(2) Position drain pan under cooler line to catch
material flushed through coolers and lines.
(3) Reverse flush each cooler using hand operated
suction gun filled with mineral spirits. Insert gun
nozzle (or hose) into cooler inlet (return) line. Then
force mineral spirits through into line and through
cooler.(4) Continue reverse flushing until fluid exiting in-
let (pressure) line is clear and free of debris/residue.
(5) Replace radiator if fluid cannot be pumped
through main cooler. Replace auxiliary cooler if leaks
are evident, or if fluid cannot be pumped through it.
(6) Clear flushing materials from coolers and lines
with short pulses of compressed air. Insert air gun
nozzle into cooler inlet (return) line and continue
short pulses of air until all fluid is cleared from
cooler and lines.
(7) Pump one quart of fresh automatic transmis-
sion fluid through cooler and lines before reconnect-
ing cooler lines.
FLOW TESTING TRANSMISSION MAIN
COOLER
Cooler flow is checked by measuring the amount of
fluid flow through the cooler in a 20 second time pe-
riod. The test is performed with the engine running
and transmission in neutral. Fluid is then pumped
through the cooler by the transmission oil pump.
(1) Disconnect cooler inlet line at transmission fit-
ting.
(2) Securely attach hose to end of inlet line and po-
sition line in a one quart test container.
(3) Add extra quart of fluid to transmission.
(4) Use stopwatch to check flow test time.
(5) Shift transmission into neutral and set parking
brake.
(6) Start and run engine at curb idle speed and im-
mediately note cooler flow. Approximately one quart
of fluid should flow into test container in 20 second
period.
(7) If cooler flow is intermittent, flows less than
one quart in 20 seconds, or does not flow at all,
cooler is faulty and must be replaced.
TRANSMISSION COOLER LINE FITTINGS
Quick disconnect fittings are used at the transmis-
sion cooler line connections. The fitting seals and
guides are serviceable.
Replace the seals and guides whenever the fittings
exhibit leakage, or will not properly snap into place.
JAW-4 IN-VEHICLE SERVICE 21 - 187

AW-4 TRANSMISSION REMOVAL AND INSTALLATION
INDEX
page page
Oil Pump Seal Replacement............... 189
Torque Converter Stator Clutch Inspection..... 189Transmission and Torque Converter Installation . 190
Transmission and Torque Converter Removal . . 189
TRANSMISSION AND TORQUE CONVERTER
REMOVAL
(1) Raise vehicle.
(2) Drain transmission fluid and reinstall oil pan
drain plug.
(3) Remove upper half of transmission fill tube
(Fig. 50).
(4) Disconnect cooler lines at transmission. Cooler
lines have quick-disconnect fittings. Press fitting re-
lease tabs and pull cooler lines and fittings out of
case or use Special Tool 7555 to disconnect them.
(5) Support engine with safety stand and support
transmission with jack.
(6) Disconnect transmission and transfer case shift
linkage.
(7) Remove necessary exhaust components.
(8) Disconnect vehicle speed sensor wires
(9) Mark position of front and rear propeller shafts
for alignment reference. Then remove shafts from ve-
hicle.
(10) Remove rear crossmember.
(11) Disconnect transmission shift cable at trans-
mission. Then disconnect transmission throttle valve
cable at engine.(12) Disconnect necessary vacuum and fluid hoses.
(13) Remove transfer case from transmission.
(14) Disconnect and remove crankshaft position
sensor.
CAUTION: The crankshaft position sensor can be
damaged if the sensor is still in place when the
transmission is removed. To avoid damage, remove
the sensor before transmission removal.
(15) Remove starter motor.
(16) Remove bolts attaching converter to drive
plate.
(17) Remove bolts attaching converter housing to
engine.
(18) Secure transmission to jack with safety
chains.
(19) Pull transmission rearward for access to con-
verter. Then secure converter in pump with C-clamp
or strap bolted to converter housing.
(20) Remove transmission from under vehicle.
(21) Remove torque converter if converter or oil
pump seal are to be serviced.
TORQUE CONVERTER STATOR CLUTCH
INSPECTION
(1) Insert Rotating Tool 7547 into converter hub
and seat tool in one-way clutch (Fig. 51).
(2) Insert Stopper Tool 7548 in one converter hub
notch and into outer race of rotating tool.
(3) Turn rotating tool clockwise. Converter clutch
should rotate freely and smoothly. Less than 2.5 Nzm
(22 in. lbs.) of torque should be required to rotate
clutch in clockwise direction.
(4) Turn rotating tool in counterclockwise direction.
Converter clutch should lock.
(5)
Replace converter if clutch binds or will not lock.
OIL PUMP SEAL REPLACEMENT
(1) Remove converter.
(2) Remove old seal. Use blunt punch to collapse
seal and pry seal out of pump housing. Do not
scratch or damage seal bore.
(3) Lubricate lip of new seal with Mopar Mercon
transmission fluid and install seal in pump with tool
7549 (Fig. 52).
(4) Lubricate converter drive hub with Mopar Mer-
con transmission fluid.
Fig. 50 Two-Piece Transmission Fill Tube
JAW-4 TRANSMISSION REMOVAL AND INSTALLATION 21 - 189

(5) Align and install converter in oil pump.
TRANSMISSION AND TORQUE CONVERTER
INSTALLATION
(1) Mount transmission on transmission jack. Then
secure transmission to jack with safety chains.
(2) Lubricate converter drive hub and oil pump
seal lip with Mopar Mercon transmission fluid. Then
install converter. Be sure converter is fully seated in
oil pump gears before proceeding. Hold converter in
place with C-clamp or strap attached to converter
housing.
(3) Align and position transmission and converter
on engine.
(4) Remove clamp or strap used to hold torque con-
verter in place.
(5) Move transmission forward seat and it on en-
gine. Be sure torque converter hub is fully seated.
(6)
Install converter housing-to-engine bolts (Fig.
53).
(7) Install converter-to-drive plate bolts.
(8) Install and connect starter motor.
(9) Install and connect crankshaft position sensor.
(10) Install transfer case on transmission. Tighten
transfer case attaching nuts to 41 Nzm (30 ft. lbs.)
torque
(11) Connect transfer case shift linkage and vac-
uum hoses.
(12) Connect exhaust components.
(13) Install rear crossmember and remove jack
used to support transmission assembly.
(14) Connect speed sensor wire harness to sensor.
(15) Connect wire harness to park/neutral position
switch.
(16) Align and connect front and rear propeller
shafts.
Fig. 51 Checking Operation Of Torque Converter
Stator One-Way Clutch
Fig. 52 Installing Oil Pump Seal
21 - 190 AW-4 TRANSMISSION REMOVAL AND INSTALLATIONJ

AW-4 TRANSMISSION OVERHAUL
INDEX
page page
Cleaning and Inspection................... 76
Direct Clutch Overhaul................... 219
First-Reverse Brake Piston and Transmission
Case Overhaul........................ 237
Forward Clutch Overhaul.................. 223
Front Planetary Gear Overhaul............. 228
Manual Valve Shaft Overhaul.............. 205
Oil Pump Overhaul...................... 206
Overdrive Planetary Gear and Clutch Overhaul . 209Overdrive Support Overhaul................ 216
Overhaul Service Tools................... 192
Rear Planetary, No. 2 One-Way Clutch and
Output Shaft Overhaul.................. 100
Second Brake Overhaul................... 100
Sun Gear and No. 1 One-Way Clutch Overhaul . 99
Transmission Assembly and Adjustment....... 255
Transmission Disassembly................. 192
Transmission Valve Body Overhaul.......... 101
OVERHAUL SERVICE TOOLS
The special tools needed to overhaul the AW-4
transmission are provided in Tool Kit 6294. However,
Pressure Test Port Adapter 7554 is not included in
this kit and must be ordered separately. The over-
haul tool kit and test port adapter are available
through the parts division and dealer special tool
program.
TRANSMISSION DISASSEMBLY
(1) Remove torque converter.
(2) Remove lower half of filler tube if not previ-
ously removed.
(3) Remove clamps attaching wire harness and
throttle cable (Fig. 1) to transmission.(4) Remove shift lever from manual valve shaft at
left side of transmission.
(5) Remove park/neutral position switch.
(6) Remove speed sensor (Fig. 2).
Fig. 1 Typical Harness And Cable Clamp Attachment
Fig. 2 Speed Sensor Removal
21 - 192 AW-4 TRANSMISSION OVERHAULJ

(37) Disassemble second coast brake piston (Fig.
29).
(38) Remove direct and forward clutch assembly
(Fig. 30).
(39) Remove thrust bearing and race from clutch
hub (Fig. 31).
(40) Remove second coast brake band E-ring from
band pin and remove brake band (Fig. 32).
(41) Remove front planetary ring gear front bear-
ing race and remove front planetary ring gear (Fig.
33).(42) Remove thrust bearing and rear race from
ring gear (Fig. 34).
(43) Remove planetary thrust race (Fig. 35).
(44) Relieve load on planetary snap ring as follows:
Loosen transmission holding fixture. Turn transmis-
Fig. 29 Second Coast Brake Piston Components
Fig. 30 Removing Direct And Forward Clutch
Assembly
Fig. 31 Remove Bearing And Race From Clutch Hub
Fig. 32 Removing Second Coast Brake Band
21 - 200 AW-4 TRANSMISSION OVERHAULJ

sion over and allow output shaft to support transmis-
sion weight. Place wood blocks under shaft to protect
splines (Fig. 35).
(45) Remove planetary snap ring and remove plan-
etary gear (Fig. 36).
(46) Remove sun gear, input drum and one-way
Fig. 33 Removing Front Planetary Ring Gear
Fig. 34 Removing Ring Gear Bearing And Rear Race
Fig. 35 Relieving Load On Planetary Snap Ring
Fig. 36 Removing Planetary Snap Ring And Gear
JAW-4 TRANSMISSION OVERHAUL 21 - 201

(6) Measure inside diameter of stator shaft bush-
ing (Fig. 2). Take measurements at front and rear of
bushing. Diameter should be maximum of 21.58 mm
(0.08496 in.) at front and 27.08 mm (1.0661 in.) at
rear. Replace stator shaft if bushing diameter is
greater than specified.
(7) Measure oil pump clearances (Fig. 3).
²Clearance between pump driven gear and pump
body should be maximum of 0.3 mm (0.012 in).
²Clearance between tips of pump gear teeth should
be maximum of 0.3 mm (0.012 in).
²Clearance between rear surface of pump housing
and pump gears should be maximum of 0.1 mm
(0.004 in.).
(8) Replace pump body and gears if any clearance
is greater than specified.
Fig. 2 Checking Pump/Stator Shaft Bushings
Fig. 3 Checking Pump Gear Clearances
JAW-4 TRANSMISSION OVERHAUL 21 - 207

(20) Check inside diameter of clutch drum bush-
ings with bore gauge or inside micrometer (Fig. 18).
Maximum inside diameter is 27.11 mm (1.0673 in.).
Replace drum if bushing inside diameter is greater
than specified.
(21) Check inside diameter of planetary gear bush-
ing (Fig. 19). Maximum inside diameter is 11.27 mm
(0.4437 in.). Replace planetary gear if bushing inside
diameter is greater then specified.
Assembling Gear And Clutch
(1) Install thrust washer in planetary gear (Fig.
20).Grooved side of washer faces up and to-
ward front.(2) Install one-way clutch in race (Fig. 21). Flanged
side of clutch must face upward as shown.
(3) Install assembled one-way clutch and outer
race in planetary gear. Be sure flanged side of clutch
is facing upward.
(4) Install clutch pack retaining plate and snap
ring in planetary gear.
(5) Coat planetary race with petroleum jelly and
install it on planetary gear. Outside diameter of race
is 41.8 mm (1.646 in.); inside diameter is 27.1 mm
(1.067 in.).
(6) Install hub in planetary ring gear and install
snap ring.
Fig. 18 Checking Clutch Drum Bushings
Fig. 19 Checking Planetary Bushing
Fig. 20 Install Planetary Thrust Washer
Fig. 21 Assembling One-Way Clutch And Race
21 - 214 AW-4 TRANSMISSION OVERHAULJ