1994 JEEP CHEROKEE ECU

condenser. The auxiliary cooler is a serviceable com-
ponent and can be repaired if necessary.
The main and auxiliary coolers should be thor-
oughly reverse flushed if a transmission failure
contaminates the fluid. Reverse flushing the cooler
and lines will prevent sludge and particles from
flowing back into the transmission after repair.
The same flushing procedure is used for main and
auxiliary coolers. Pressure equipment is preferred for
reverse flushing. However, reverse flushing can be
performed using hand operated equipment as de-
scribed in the following procedure.
REVERSE FLUSHING PROCEDURE
(1) Disconnect cooler lines at transmission. Refer
to Figure 21 for cooler line fitting identification.
Front fitting is outlet to cooler and rear fitting is in-
let from cooler.
(2) Position drain pan under cooler outlet line to
material flushed through cooler and lines.
(3) Reverse flush cooler using hand operated suc-
tion gun filled with mineral spirits. Insert gun nozzle
(or hose) into cooler inlet (return) line. Then force
mineral spirits through Line and cooler.
(4) Continue reverse flushing until fluid exiting in-
let (pressure) line is clear and free of debris/residue.
Replace radiator if fluid cannot be pumped
through cooler.
(5) Clear flushing materials from cooler 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.
(6) Pump one quart of fresh automatic transmis-
sion fluid through cooler and lines before reconnect-
ing cooler lines.
TRANSMISSION COOLER FLOW TESTING
The transmission main and auxiliary coolers
should be flow tested whenever a fluid overheat con-
dition is suspected. An overheat condition is indi-
cated when the fluid changes from the normal red, to
a dark orange, or brown color.
The same method of flow testing is used for both
coolers.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 fitting.
(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.
SERVICING TRANSMISSION COOLER LINES AND
FITTINGS
Fitting Types
The transmission cooler lines are attached with
quick disconnect fittings.
A flange on the cooler line serves as the sealing
mechanism. The wire retainer clip (Fig. 22), secures
the cooler line in the fitting by this flange. The clip
fits behind the flange to hold the line in place.
Three different fitting styles may be used. Type 1
fittings have the retainer clip exposed (Fig. 22). Type
2 fittings have the retainer clip and fitting body en-
cased in a shrink wrap material (Fig. 23). Type 3 fit-
tings have the retainer clip encased in a metal sleeve
crimped onto the fitting body (Fig. 24).
Fitting Release Tool
A release tool isrequiredto disconnect each of the
fitting types. A plastic tool is clipped directly to one
of the cooler lines on models with the type 2 and 3
fittings. This tool can also be used to disconnect type
1 fittings. The tool is needed to spread the wire re-
tainer clip in each fitting. The clip must be opened in
order to release the cooler line from the fitting.
Fig. 21 Identifying Transmission Cooler Lines
Fig. 22 Type 1 Quick Disconnect Fitting
21 - 106 30RH/32RH IN-VEHICLE SERVICEJ

Fitting And Cooler Line Service
The cooler lines and quick disconnect fittings are
NOT serviceable. Damaged fittings or cooler lines
are to be replaced as assemblies.
Fittings swedged into cooler line hoses (Fig. 25) are
serviced only as part of the entire cooler line.
DISCONNECTING COOLER LINES WITH
QUICK DISCONNECT FITTINGS
(1) If fitting and cooler line are encrusted with
dirt, mud, or grease, clean fitting and cooler line
with Mopar spray type carburetor or brake cleaner.
Plastic release tool will not fit into retainer clip if fit-
ting is full of foreign material.
(2) Slide small plastic release tool into fitting until
tool bottoms against flange on cooler line (Fig. 26).
(3) Push and turn tool to spread retainer clip and
pull cooler line out of fitting (Fig. 26).
(4) Cover open ends of cooler lines and fittings to
prevent dirt entry.
(5) Inspect condition of fitting. Replace transmis-
sion fitting as an assembly if fitting body or retainer
clip is damaged. Replace cooler line as assembly, if
fitting swedged into cooler line hose, is damaged.
REATTACHING COOLER LINES WITH QUICK
DISCONNECT FITTINGS
(1) If transmission or radiator fittings require re-
placement, apply Mopar Lock N' Seal, or Loctite 242
to fitting threads before installation.
(2) Wipe off cooler line and fitting with clean, dry
cloth.
(3) Insert cooler line into fitting. Then push line
inward until retainer clip secures line. A snap or
click sound will be heard and felt through the line
when the retainer clip seats behind the cooler line
flange.
(4)Pull outward on cooler lines to verify that
they are properly secured.
CAUTION: The wire retainer clips must secure the
cooler lines in the fittings. If the clips are deformed, or
distorted, normal fluid pressure could unseat the cooler
lines resulting in fluid loss and transmission damage.
Be very sure the cooler lines are firmly secured by the
retainer clip as described in step (4) above.
Fig. 23 Type 2 Quick Disconnect fitting
Fig. 24 Type 3 Quick Disconnect fitting
Fig. 25 Transmission And Cooler Line Fitting Placement
Fig. 26 Disconnecting Cooler Line With Release
Tool (Type 2 Fitting Shown)
J30RH/32RH IN-VEHICLE SERVICE 21 - 107

30RH/32RH TRANSMISSION REMOVAL AND INSTALLATION
INDEX
page page
ConverterÐPump SealÐDrive Plate Service . . . 109
Transmission and Converter Installation....... 109Transmission and Converter Removal........ 108
TRANSMISSION AND CONVERTER REMOVAL
(1) Remove fan shroud attaching bolts.
(2) Disconnect transmission fill tube at upper
bracket.
(3) Raise vehicle.
(4) Remove inspection cover from converter hous-
ing and remove skid plate for access, if necessary.
(5) Remove transmission fill tube and fill tube
O-ring.
(6) Remove starter motor.
(7) Mark propeller shafts and axle yokes for align-
ment reference.
(8) Disconnect propeller shafts at yokes. Secure
shafts to frame rails with wire.
(9) Disconnect exhaust pipes at exhaust manifolds,
if necessary.
(10) Drain transfer case lubricant.
(11) Disconnect vehicle speed sensor wires.
(12) Disconnect transfer case shift linkage.
(13) Disconnect gearshift linkage and throttle ca-
ble at transmission levers.
(14) Disconnect park/neutral position switch wires.
(15) Disconnect and remove crankshaft position
sensor. Retain sensor bolt for reinstallation.
CAUTION: The crankshaft position sensor can be
damaged during transmission removal (or installa-
tion) if the sensor is still bolted to the engine block.
To avoid damage, remove the sensor before remov-
ing the transmission.
(16) Remove converter housing access cover and
mark drive plate and converter for alignment refer-
ence.
(17) Remove bolts attaching converter to drive
plate.
(18) Support engine with support stand.
(19) Support transmission-transfer case assembly
with transmission jack. Secure transmission to jack
with safety chain.
(20) Remove bolts/nuts attaching cushion and
torque arm bracket to skid plate (Fig. 1).
(21) Remove skid plate, or rear crossmember, if
equipped.
(22) Lower transmission slightly and disconnect
cooler lines at transmission.Refer to In-Vehicle
Service section for procedures.(23) Remove bolts attaching transmission to en-
gine.
(24) Move transmission and converter rearward
until clear of crankshaft.
(25) Hold converter in position and lower transmis-
sion until converter housing clears engine.
(26) Remove converter from transmission.
(27) Remove transfer case from transmission.
(28) If necessary, following components can now be
serviced:
²torque converter
²torque converter drive plate
²oil pump seal
²engine rear core hole plugs
²engine rear oil galley plugs
Fig. 1 Transmission Rear Mount
21 - 108 30RH/32RH TRANSMISSION REMOVAL AND INSTALLATIONJ

(1) Lubricate converter drive hub and pump seal
with Mopar ATF Plus, or Dexron II transmission
fluid. Then install converter. Turn converter back
and forth to align drive slots in converter hub with
pump gear lugs. Be sure converter is fully seated in
pump (Fig. 5).
(2) Temporarily secure converter with C-clamp or
metal strap attached across converter housing.
(3) Position transmission on jack and secure it
with safety chains.
(4) Raise transmission and align converter with
drive plate.
(5) Move transmission forward. Then raise, lower
or tilt transmission to align converter housing with
engine block dowels.
(6) Install two converter housing lower attaching
bolts and tighten bolts to draw housing toward en-
gine.
(7) Install and tighten converter attaching bolts.
(8) Install and tighten bolts that attach transmis-
sion to engine (Fig. 6).
(9) Install crankshaft position sensor as follows:
CAUTION: Clearance between the sensor pickup
face and driveplate ring gear must be correctly es-
tablished before engine startup. A cardboard
spacer, attached to the sensor face, is used for thispurpose. Failure to establish correct clearance will
result in sensor breakage.
(a) Remove any remaining fragments of original
cardboard spacer from sensor pickup face.
Fig. 5 Checking Torque Converter Seating
Fig. 6 Transmission Attachment
21 - 110 30RH/32RH TRANSMISSION REMOVAL AND INSTALLATIONJ

(32) Remove governor body and park gear as as-
sembly (Fig. 20). Work park gear out of rear support
and slide assembly off output shaft.
(33) Remove planetary geartrain as assembly (Fig.
21). Support geartrain with both hands during re-
moval. Do not allow machined surfaces on output
shaft to become nicked or scratched.
(34) Loosen rear band adjusting screw until band
is fully released and does not grip low reverse drum.
(35) Remove snap ring that secures low-reverse
drum to rear support (Fig. 22).
(36) Remove rear band lever pins as follows:
(a) On 30RH transmission, rear band has only
one pivot pin. Remove pin with parallel jaw snap
ring pliers (Fig. 23). Spread plier jaws in pin bore
to grip pin. Then remove pin with a twist and pull
motion.(b) On 32RH transmission, rear band has two
pins. Remove pivot pin and reaction pin with par-
allel jaw snap ring pliers (Fig. 24).
(37) Remove rear band lever, link and strut.
(38) Mark position of rear support for assembly
reference (Fig. 25). Use scriber or center punch to
mark case and support.
(39) Remove rear support bolts and remove support
from low-reverse drum and case (Fig. 26). Keep rear
support bolts together for assembly reference.
(40) Remove bolts attaching overrunning clutch
cam to case (Fig. 27).
(41) Remove low-reverse drum and overrunning
clutch as assembly. Slide drum and clutch through
rear band and out of case. Set drum and clutch as-
sembly aside for cleaning and inspection.
(42) Remove rear band and link from case.
(43) Compress front servo rod guide about 3 mm
(1/8 in.) with Valve Spring Compressor Tool
C-3422-B (Fig. 28). A C-clamp and tool C-4470 can
also be used to compress rod guide.
Fig. 20 Removing/Installing Governor Body And
Park Gear
Fig. 21 Planetary Geartrain Removal
Fig. 22 Removing Low-Reverse Drum Snap Ring
Fig. 23 Removing Rear Band Lever Pivot Pin (30RH)
21 - 116 30RH/32RH TRANSMISSION OVERHAULJ

GOVERNOR AND PARK GEAR OVERHAUL
GOVERNOR/PARK GEAR DISASSEMBLY
(1) Loosen bolts attaching governor to park gear.
(2) Remove governor snap ring and locating snap
ring from output shaft (Fig. 39).
(3) Remove E-clip securing governor valve shaft
and remove shaft and valve from governor body.
(4) Slide governor and park gear off output shaft.
(5) Remove governor retaining bolts and separate
governor from park gear.
(6) Remove governor filter from park gear. Keep
filter with governor body.
(7) Remove governor weight snap ring and remove
weight assembly from governor body. Remove inner
snap ring and separate governor weights.
GOVERNOR/PARK GEAR CLEANING AND
INSPECTION
Clean the governor and park gear components in
solvent and dry with compressed air.
Examine the governor components carefully (Fig.
39). Discard any snap rings or E-clips if distorted, or
worn. Be sure the governor weights operate freely in
the bores and do not bind. Also verify that the gov-
ernor valve slides freely on the shaft and in the bore.
Minor scratches, or burrs on governor components
can be cleaned up with oil-soaked crocus cloth. How-
ever, do not attempt to salvage components that are
severely worn or scored.
The governor valve used in 30RH/32RH trans-
missions built starting with the 1992 model year,
is now made of aluminum. In addition, the out-
put shaft has been spotfaced to accept the newaluminum valve (Fig. 39). The aluminum valve
must not be used in prior transmissions. The
valve can only be used with an output shaft that
has been spotfaced for valve end clearance. In
addition, the governor body and output shaft
must be properly indexed during reassembly. Be
sure to index these components as described in
the Transmission Assembly and Adjustment pro-
cedures.
Check condition of the park gear seal rings, ring
grooves and gear teeth (Fig. 40). Replace the gear as
an assembly if the teeth or ring grooves are worn, or
damaged.
Replace the park gear front and rear seal rings if
cracked, or worn. The production style front ring is a
plain type and the rear ring is a hook style. If re-
placement rings are both hook-style, be sure the ring
ends are properly hooked together.ASSEMBLING GOVERNOR AND PARK GEAR
(1) Coat governor body bores and valves with
transmission fluid.
(2) Assemble governor weights and springs. Then
install weight assembly in governor body but do not
install valve and shaft at this time. These parts are
not installed until after governor and park gear are
in place on output shaft.
(3) Install new seal rings on park gear if neces-
sary.
(4) Insert filter screen in park gear and position
governor body on park gear.
Fig. 38 Correct Position Of Sprag And Spring
Fig. 39 Governor Components
J30RH/32RH TRANSMISSION OVERHAUL 21 - 121

CAUTION: The pump inner gear is a one way fit.
The bore on one side of the gear inside diameter
(I.D.) is chamfered. Be sure the chamfered side
faces forward (to front of pump).
(6) Install new thrust washer on hub of reaction
shaft support. Lubricate washer with transmission
fluid or petroleum jelly.
(7) If reaction shaft seal rings are being replaced,
install new seal rings on support hub (Fig. 54). Lu-
bricate seal rings with transmission fluid or petro-
leum jelly after installation. Squeeze each ring until
ring ends are securely hooked together.
CAUTION: The reaction shaft support seal rings will
break if overspread, or twisted. If new rings are be-
ing installed, spread them only enough for installa-
tion. Also be very sure the ring ends are securely
hooked together after installation. Otherwise, the
rings will either prevent pump installation, or break
during installation.
(8) Install reaction shaft support on pump housing
(Fig. 55).
(9) Align reaction support on pump housing. Use
alignment marks made at disassembly. Or, rotatesupport until bolt holes in support and pump housing
are all aligned (holes are offset for one-way fit).
(10) Install all bolts that attach support to pump
housing. Then tighten bolts finger tight.
(11) Tighten support-to-pump bolts to required
torque as follows:
(a) Reverse pump assembly and install it in
transmission case. Position pump so bolts are fac-
ing out and are accessible.
(b) Secure pump assembly in case with 2 or 3
bolts, or with pilot studs.
(c) Tighten support-to-pump bolts to 20 Nzm (15
ft. lbs.).
(d) Remove pump assembly from transmission case.
(12) Install new oil seal in pump with Special Tool
C-4193 and Tool Handle C-4171 (Fig. 56). Be sure
seal lip faces inward.
(13) Install new seal ring around pump housing.
Be sure seal is properly seated in groove.
(14) Lubricate lip of pump oil seal and O-ring seal
with transmission fluid.
FRONT CLUTCH OVERHAUL
FRONT CLUTCH DISASSEMBLY
(1) Remove waved snap ring and remove pressure
plate, clutch plates and clutch discs (Fig. 57).
(2) Compress clutch piston spring with Compressor
Tool C-3575-A (Fig. 58). Be sure legs of tool are
seated squarely on spring retainer before compress-
ing spring.
Fig. 52 Supporting Pump And Installing Outer Gear
Fig. 53 Pump Inner Gear Installation
Fig. 54 Hub Seal Ring Position
Fig. 55 Assembling Reaction Shaft Support And
Pump Housing
J30RH/32RH TRANSMISSION OVERHAUL 21 - 125

able. It will be necessary to replace the retainer
if either bushing is scored, or worn.
Inspect the piston and retainer seal surfaces for
nicks or scratches. Minor scratches can be removed
with crocus cloth. However, replace the piston and/or
retainer if the seal surfaces are seriously scored.
FRONT CLUTCH ASSEMBLY
(1) Soak clutch discs in transmission fluid while
assembling other clutch parts.
(2) Install new seals on piston and in hub of re-
tainer. Be sure lip of each seal faces interior of clutch
retainer.
(3) Lubricate lips of piston and retainer seals with
liberal quantity of Door Eze, or petroleum jelly. Then
lubricate retainer hub, bore and piston with trans-
mission fluid.
(4) Install clutch piston in retainer (Fig. 61). Use
twisting motion to seat piston in bottom of retainer.
Do not attempt to push the piston straight in.
This could fold the seals over causing leakage
and clutch slip.
(5) Position spring in clutch piston (Fig. 62).(6) Position spring retainer on top of piston spring
(Fig. 63).Make sure retainer is properly in-
stalled. Small raised tabs should be facing up-
ward. Semicircular lugs on underside of retainer
are for positioning retainer in spring.
(7) Compress piston spring and retainer with Com-
pressor Tool C-3575-A (Fig. 64). Then install new
snap ring to secure spring retainer and spring.
(8) Install clutch plates and discs (Fig. 57). Install steel
plate then disc until all plates and discs are installed.
(9) Install pressure plate and waved snap ring
(Fig. 57).
(10) Check clutch plate clearance (Fig. 64). Clear-
ance should be 1.70 to 3.40 mm (0.067 to 0.134 in.).
If clearance is incorrect, clutch discs, plates pressure
plates and snap ring may have to be changed.
Fig. 59 Front Clutch Piston Retainer Check Ball Location
Fig. 60 Retainer Bushing Locations
Fig. 61 Front Clutch Piston Installation
Fig. 62 Clutch Piston Spring Installation
Fig. 63 Correct Spring Retainer Installed Position
J30RH/32RH TRANSMISSION OVERHAUL 21 - 127