(b) Position band and link in case (Fig. 135).
(c) Slide low-reverse drum through band (Fig.
136). Then tilt drum slightly and start clutch race
into overrunning clutch rollers.
(d) Rotate drum in clockwise direction and push
drum inward until race is seated in overrunning
clutch.
(e) Install rear band lever and pivot pin. Be sure
lever pivot pin is fully seated in case afterward.
(3) Hold low-reverse drum in position and install
rear support (Fig. 137)(4) Align support with punch marks made during
disassembly.
(5) Install and tighten rear support bolts to 17 Nzm
(150 in. lbs.) torque.
(6) Install snap ring that retains low-reverse drum
to hub of rear support (Fig. 138).
PLANETARY GEARTRAIN AND OUTPUT
SHAFT INSTALLATION
(1) Lubricate output shaft, rear support bore and
low-reverse drum hub with transmission fluid.
(2) Install assembled output shaft and planetary
geartrain in case (Fig. 139).
Fig. 135 Rear Band Positioned In Case (30RH)
Fig. 136 Low-Reverse Drum And Band Lever
Installation (30RH)
Fig. 137 Rear Support Installation
Fig. 138 Installing Low-Reverse Drum Snap Ring
Fig. 139 Installing Output Shaft And Planetary
Geartrain
21 - 158 30RH/32RH TRANSMISSION OVERHAULJ
(3) Move input shaft in and out and record read-
ing. End play should be 0.56 - 2.31 mm (0.022 - 0.091
in.).
(4) If end play is incorrect, transmission is incor-
rectly assembled, or output shaft thrust washer
and/or thrust plate are worn and need to be changed.
VALVE BODY INSTALLATION
(1) Install new manual lever shaft seal in case.
Use 15/16 deep well socket to install seal.
(2) Make sure neutral switch hasnotbeen in-
stalled in case. Remove switch if necessary as it will
interfere with valve body installation.
(3) Install new seal rings on accumulator piston
(Fig. 160). Lubricate accumulator piston, seals and
accumulator bore with transmission fluid.
(4) Install accumulator piston and spring (Fig. 160)
in case.(5) Place valve body manual lever in low to move
park lock rod rearward.
(6) Position valve body on case. Work park rod past
sprag and install valve body-to-case bolts finger
tight.
(7) Install park/neutral position switch in case.
Tighten switch to 34 Nzm (25 ft. lbs.) torque.
(8) Align valve body on case (Fig. 161).
(9) Install and tighten valve body-to-case bolts al-
ternately and evenly to 12 Nzm (105 in. lbs.) torque.
Start at center and work outward when tightening
bolts.Do not overtighten valve body bolts. This
could result in distortion and cross leakage af-
ter installation..
(10) Connect converter clutch solenoid wire to case
connector (Fig. 161).
(11) Install new filter on valve body (Fig. 162).
Tighten filter screws to 4 Nzm (35 in. lbs.).
BAND ADJUSTMENT AND OIL PAN
INSTALLATION
(1) Adjustfront bandas follows:
(a) Loosen locknut.
(b) Tighten adjusting screw to 72 in. lbs. torque.
(c) Back off front band adjusting screw as fol-
lows:
²On 30RH (2.5L), back adjusting screw off 2
1/2 turns
Fig. 158 Installing Oil Pump And Reaction Shaft
Support
Fig. 159 Checking Input Shaft End Play
Fig. 160 Installing Accumulator Piston And Spring
Fig. 161 Valve Body Installation
J30RH/32RH TRANSMISSION OVERHAUL 21 - 163
²On 32RH (4.0L), back adjusting screw off 2
1/4 turns
(d) Hold adjusting screw in position and tighten
locknut to 34 Nzm (25 ft. lbs.).
(2) Adjustrear bandas follows:
(a) Loosen locknut.
(b) Tighten adjusting screw as follows:
²On 32RH, tighten screw to 8 Nzm (72 in. lbs)
torque
²On 30RH, tighten screw to 5 Nzm (41 in. lbs.)
torque.
(c) Back off rear band adjusting screw as follows:
²On 30RH (2.5L), back adjusting screw off 7 turns
²On 32RH (4.0L), back adjusting screw off 4 turns
(d) Hold adjusting screw in place and tighten
locknut to 34 Nzm (25 ft. lbs.) torque.
(3) Install new pan gasket on transmission and in-
stall oil pan. Tighten pan bolts to 17 Nzm (13 ft. lbs.).(4) Turn transmission over.
EXTENSION HOUSING, CONTROL LEVER AND
CONVERTER INSTALLATION
(1) Install throttle valve and manual valve levers
on shaft.
(2) Position new extension adapter housing gasket
on transmission case. Use petroleum jelly to hold
gasket in place.
(3) Install new rear seal in extension housing if re-
quired.
(4) Install extension/adapter housing on transmis-
sion case. Tighten housing fasteners to 33 Nzm (24 ft.
lbs.). Be sure park lock rod is properly engaged in
sprag before tightening fasteners.
(5) Lubricate converter hub with transmission
fluid and carefully install converter. Turn converter
back and forth until seated.
(6) Secure converter in oil pump before mounting
transmission on jack and before moving transmission
back under vehicle. Use metal strapping, C-clamp, or
locking pliers to hold converter in place. Attach hold-
ing tool to converter housing.
CAUTION: The transmission cooler and lines must
be reverse flushed if overhaul corrected a malfunc-
tion that generated sludge, metal particles, or
clutch friction material. The torque converter and
drainback valve should also be replaced as they
will also be contaminated. Debris and residue NOT
flushed from the cooler and lines will flow back into
the transmission and converter. The result will be a
repeat failure and shop comeback.
Fig. 162 Fluid Filter Installation
21 - 164 30RH/32RH TRANSMISSION OVERHAULJ
AW-4 AUTOMATIC TRANSMISSION
CONTENTS
page page
AW-4 AUTOMATIC TRANSMISSION........ 165
AW-4 IN-VEHICLE SERVICE.............. 182
AW-4 TRANSMISSION DIAGNOSIS......... 176
AW-4 TRANSMISSION OVERHAUL......... 201AW-4 TRANSMISSION REMOVAL AND
INSTALLATION....................... 198
GENERAL INFORMATION................ 165
GENERAL INFORMATION
INDEX
page page
Components and Operation................. 166
Description............................. 165
First/Second/Third/Reverse Components....... 168
Fourth Gear Overdrive Components.......... 167
Geartrain Operation and Application Charts..... 169Hydraulic System........................ 169
Recommended Fluid and Capacity........... 166
Torque Converter........................ 167
Transmission Identification.................. 166
Transmission Ranges and Shift Lever Positions . . 166
DESCRIPTION
AW-4 Transmission Overhaul
The AW-4 is a 4-speed, electronically controlled au-
tomatic transmission (Fig. 1). The AW-4 is used in XJ
models with a 4.0L engine.
Running gear consists of an oil pump, planetary
gear sets, clutch and brake units, hydraulic accumu-
lators, a valve body with electrical solenoids and a
transmission control module (TCM). Cables are usedfor shift and throttle pressure control. A park/neutral
position switch permits engine starting in Park and
Neutral range only.
The valve body solenoids are controlled by signals
from the transmission control module (TCM). Signal
sequence is determined by vehicle speed and throttle
position.
Fourth gear is an 0.75:1 ratio overdrive range.
First, second, third and reverse gear are conventional
Fig. 1 AW-4 Automatic Transmission
JAW-4 AUTOMATIC TRANSMISSION 21 - 165
ranges. Third gear ratio is 1:1. A separate planetary
gear set provides overdrive operation in fourth gear.
TRANSMISSION RANGES AND SHIFT LEVER
POSITIONS
The AW-4 transmission has six ranges and shift le-
ver positions. Park, Reverse and Neutral are conven-
tional and mechanically operated. The 1-2, 3 and D
ranges provide electronically controlled shifting.
The 1-2 position provides first and second gear
only. The 3 position provides first, second and third
gear.
The D range provides first through fourth gear.
Overdrive fourth gear range is available only when
the shift lever is in D position (Fig. 2).
TRANSMISSION IDENTIFICATION
The transmission I.D. plate is attached to the case
(Fig. 3). The plate contains the transmission serial
and model numbers. Refer to the information on this
plate when ordering service parts.
RECOMMENDED FLUID AND CAPACITY
Recommended and preferred fluid for the AW-4
transmission is Mopar Dexron IIE/Mercon.
Mopar Dexron II can be used but only in emer-
gency situations where Mercon fluid is not available.
Approximate refill capacity for the AW-4 is 8.0 li-
ters (16.9 pints or 8.45 quarts).
COMPONENTS AND OPERATION
ELECTRONIC CONTROLS
The AW-4 is electronically controlled in 1, 2, 3 and
D ranges. Controls consist of the transmission control
module (TCM), valve body solenoids and various sen-
sors. The sensors monitor vehicle speed, throttle
opening, shift lever position and brake pedal applica-
tion.
TRANSMISSION CONTROL MODULE (TCM)
The module determines shift and converter clutch
engagement timing based on signals from sensors.
The valve body solenoids are activated, or deacti-
vated accordingly.
The TCM has a self diagnostic program. Compo-
nent and circuitry malfunctions can be diagnosed
with the DRB scan tool. Once a malfunction is noted
and stored in control module memory, it is retained
even after the problem has been corrected. To cancel
a stored malfunction, disconnect and reconnect the
9Trans.9fuse in the module harness.
TRANSMISSION VALVE BODY SOLENOIDS
The solenoids are mounted on the valve body and
operated by the TCM. The solenoids control operation
of the converter clutch and shift valves in response to
input signals from the module.
SENSORS
Sensors include:
²throttle position sensor (TPS)
²transmission speed sensor
²vehicle speed sensor
²park/neutral position switch
²brake switch
The throttle position sensor is mounted on the
throttle body. It electronically determines throttle po-
sition and relays this information to the transmission
control module to determine shift points and con-
verter clutch engagement.
Fig. 2 AW-4 Shift Lever Positions And Transmission
Ranges
Fig. 3 Transmission Identification
21 - 166 AW-4 AUTOMATIC TRANSMISSIONJ
The manual valve, 1-2 shift valve, primary regula-
tor valve, accumulator control valve, check balls, so-
lenoids and oil strainers are located in the lower
body section (Fig. 10). The remaining control and
shift valves plus check balls and one additional oil
strainer are located in the upper body section (Fig.
11).
Manual Valve
The manual valve is operated by the gearshift link-
age. The valve diverts fluid to the apply circuits ac-
cording to shift lever position.Primary Regulator Valve
The primary regulator valve (Fig. 13) modulates
line pressure to the clutches and brakes according to
engine load. The valve is actuated by throttle valve
pressure.
During high load operation, the valve increases line
pressure to maintain positive clutch and brake en-
gagement. At light load, the valve decreases line
pressure just enough to maintain smooth engage-
ment.
Fig. 10 Upper Body Components
Fig. 11 Lower Body Components
21 - 170 AW-4 AUTOMATIC TRANSMISSIONJ
Secondary Regulator Valve
The secondary regulator valve (Fig. 16) regulates
converter clutch and transmission lubrication pres-
sure. When primary regulator valve pressure exceeds
requirements for clutch engagement or transmission
lubrication, the secondary regulator valve is moved
upward exposing the drain port. Excess pressure
then bleeds off as needed. As pressure drops, spring
tension moves the valve downward closing the drain
port.Converter Clutch Relay Valve
The relay valve (Fig. 17) controls fluid flow to the
converter clutch. The valve is operated by line pres-
sure from the 1-2 shift valve and is controlled by so-
lenoid valve number three.
1-2 Shift Valve
The 1-2 shift valve (Fig. 18) controls 1-2 upshifts
and downshifts. The valve is operated by the No. 2
valve body solenoid and line pressure from the man-
ual valve, second coast modulator valve and the 2-3
shift valve.
Fig. 16 Secondary Regulator Valve
Fig. 17 Converter Clutch Relay Valve
Fig. 18 1-2 Shift Valve
21 - 172 AW-4 AUTOMATIC TRANSMISSIONJ
(2) Verify transmission throttle cable operation.
Repair or replace cable if necessary.
(3) Check engine throttle operation. Operate accel-
erator pedal and observe injector throttle plate move-
ment. Adjust linkage if throttle plate does not reach
wide open position.
(4) Check transmission fluid level when fluid is at
normal operating temperature. Start engine. Shift
transmission through all gear ranges then back to
Neutral. Correct level is to Full or Add mark on dip-
stick with engine at curb idle speed.
(5) Check and adjust park/neutral position switch
if necessary.
(6) Check throttle position sensor adjustment and
operation. Adjust the sensor if necessary.
MANUAL SHIFTING TEST
(1) This test determines if problem is related to
mechanical or electrical component.
(2) Stop engine and disconnect transmission con-
trol module or module fuse.
(3) Road test vehicle. Shift transmission into each
gear range. Transmission should operate as follows:
²lock in Park
²back up in Reverse
²not move in Neutral
²provide first gear only with shift lever in 1-2 posi-
tion
²operate in third gear only with shift lever in 3 po-
sition
²operate in overdrive fourth gear in D position
(4) If transmission operates as described, proceed
to next step. However, if forward gear ranges were
difficult to distinguish (all feel the same), or vehicle
would not back up, refer to diagnosis charts. Do not
perform stall or time lag tests.
CAUTION: Do not overspeed the engine during the
next test step. Ease off the throttle and allow the
vehicle to slow before downshifting.
(5) Continue road test. Manually downshift trans-
mission from D to 3, and from 3 to 1-2 position. Then
manually upshift transmission through forward
ranges again.
(6) If transmission operation is OK, perform stall,
time lag and pressure tests. If transmission shifting
problem is encountered, refer to diagnosis charts.
(7) If a problem still exists, continue testing with
DRB scan tool.
HYDRAULIC PRESSURE TEST
PRESSURE TEST PROCEDURE
(1) Connect pressure test gauge to test port on pas-
senger side of transmission. Use Adapter 7554 to con-
nect gauge. Be sure test gauge has minimum
capacity of 300 psi (2100 kPa).(2) Be sure transmission fluid is at normal operat-
ing temperature.
(3) Apply parking brakes and block wheels.
WARNING: DO NOT ALLOW ANYONE TO STAND
AT THE FRONT OR REAR OF THE VEHICLE WHILE
PERFORMING THE FOLLOWING STEPS IN THE
PRESSURE TEST.
(4) Check and adjust engine curb idle speed.
(5) Apply (and hold) service brakes.
(6) Shift transmission into D range and note line
pressure with engine at curb idle speed. Pressure
should be 61-to-70 psi (421-to-481 kPa).
(7) Press accelerator pedal to wide open throttle
position and note line pressure. Pressure should be
173-to-209 psi (1196-to-1442 kPa).
CAUTION: Do not hold wide open throttle for more
than 3-4 seconds at a time.
(8) Shift transmission into Reverse and note line
pressure with engine at curb idle speed. Pressure
should be 75-to-90 psi (519-to-618 kPa).
(9) Press accelerator to wide open throttle position
and note line pressure in Reverse. Pressure should
be 213-to-263 psi (1471-to-1814 kPa).
CAUTION: Do not hold wide open throttle for more
than 4 seconds.
(10) If line pressure is not within specifications,
adjust transmission throttle cable and repeat pres-
sure test.
Fig. 27 Pressure Test Gauge Connection
JAW-4 TRANSMISSION DIAGNOSIS 21 - 177