1995 JEEP YJ oil pressure

happens when the container delivery mechanism is im-
properly calibrated. Always check the lubricant level af-
ter filling to avoid an under fill condition.
A correct lubricant level check can only be made
when the vehicle is level; use a drive-on hoist to en-
sure this. Also allow the lubricant to settle for a
minute or so before checking. These recommenda-
tions will ensure an accurate check and avoid an un-
der-or-overfill condition.
HARD SHIFTING
Hard shifting is usually caused by a low lubricant
level, improper or contaminated lubricants, compo-
nent damage, incorrect clutch adjustment, or by a
damaged clutch pressure plate or disc.
Substantial lubricant leaks can result in gear, shift
rail, synchro and bearing damage. If a leak goes un-
detected for an extended period, the first indications
of a problem are usually hard shifting and noise.
Incorrect or contaminated lubricants can also con-
tribute to hard shifting. The consequence of using
non-recommended lubricants is noise, excessive wear,
internal bind and hard shifting.
Improper clutch release is a frequent cause of hard
shifting. Incorrect adjustment or a worn, damaged
pressure plate or disc can cause incorrect release. If
the clutch problem is advanced, gear clash during
shifts can result.
Worn or damaged synchro rings can cause gear clash
when shifting into any forward gear. In some new or re-
built transmissions, new synchro rings may tend to
stick slightly causing hard or noisy shifts. In most
cases, this condition will decline as the rings wear-in.
TRANSMISSION NOISE
Most manual transmissions make some noise dur-
ing normal operation. Rotating gears generate a mild
whine that is audible but only at extreme speeds.
Severe, highly audible transmission noise is gener-
ally the result of a lubricant problem. Insufficient,
improper, or contaminated lubricant will promote
rapid wear of gears, synchros, shift rails, forks and
bearings. The overheating caused by a lubricant
problem, can also lead to gear breakage.
TRANSMISSION REMOVAL
(1) Shift transmission into first or third gear. Then
raise vehicle on hoist.
(2) Support engine with adjustable jack stand. Po-
sition wood block between jack and oil pan to avoid
damaging pan.
(3) Disconnect necessary exhaust system components.
(4) Remove skid plate.
(5) Disconnect rear cushion and bracket from
transmission (Fig. 5).
(6) Remove rear crossmember.
Fig. 5 Rear Mount Components (YJ Shown)
JAX 4/5 MANUAL TRANSMISSION 21 - 3

30RH/32RH AUTOMATIC TRANSMISSION
GENERAL INFORMATION
INDEX
page page
Recommended Fluid....................... 67
Torque Converter......................... 67
Transmission Application.................... 67
Transmission Changes and Parts Interchangeability.. 67
Transmission Controls and Components........ 67
Transmission Identification.................. 67
TRANSMISSION APPLICATION
Chrysler 30RH and 32RH automatic transmissions
are used in XJ/YJ models. Both are 3-speed auto-
matic transmissions with a gear-type oil pump, two
clutches and bands and a planetary gear system (Fig.
1).
The 30RH is used in XJ/YJ models with a 2.5L en-
gine. The 32RH is used in YJ models with a 4.0L en-
gine.
TORQUE CONVERTER
A three element, torque converter is used for all
applications. The converter consists of an impeller,
stator, and turbine.
The converter used with 30RH/32RH transmissions
has a converter clutch. The clutch is engaged by an
electrical solenoid and mechanical module on the
valve body. The solenoid is operated by the power-
train control module.
The torque converter is a welded assembly and is
not a repairable component. The converter is serviced
as an assembly.
RECOMMENDED FLUID
The recommended and preferred fluid for 30RH/
32RH transmissions is Mopar ATF Plus, Type 7176.
Dexron II is not really recommended and should
only be used when ATF Plus is not available.
TRANSMISSION IDENTIFICATION
The transmission identification numbers are
stamped on the left side of the case just above the oil
pan gasket surface (Fig. 2). The first set of numbers
is the transmission part number. The next set of code
numbers set is the date of build. The final set of code
numbers represents the transmission serial number.
TRANSMISSION CHANGES AND PARTS
INTERCHANGEABILITY
1995 transmissions are similar to previous models
but only in appearance. Current transmissions are
dimensionally different. Do not interchange new/oldparts. Different dimensions, fluid passages, input/
output shafts, cases, bands, valve bodies and gover-
nor assemblies are just a few of the changed items.
CAUTION: Special bolts are used to attach the
driveplate to the crankshaft on models with a 2.5L
engine and 30RH transmission,. These bolts have a
smaller hex head for torque converter clearance.
DO NOT interchange these bolts with similar size
bolts for any reason.
Different governor weight assemblies are used in
30RH/32RH transmissions. The 30RH weight assem-
bly is much the same as in previous years. However,
the 32RH has a three stage governor weight assem-
bly consisting of the outer weight, a smaller weight
spring, and a new intermediate weight. Refer to the
overhaul and in-vehicle service sections for more de-
tailed information.
Plastic check balls are now used in many 30RH/
32RH valve bodies. The new check balls entered pro-
duction as a running change. Plastic and steel check
balls are not interchangeable.
A converter drainback check valve has been added
to the fluid cooler system. The one-way valve is lo-
cated in the transmission outlet (pressure) line. The
valve prevents fluid drainback when the vehicle is
parked for lengthy periods.
TRANSMISSION CONTROLS AND COMPONENTS
The transmission hydraulic control system per-
forms five basic functions, which are:
²pressure supply
²pressure regulation
²flow control
²clutch/band apply and release
²lubrication
Pressure Supply And Regulation
The oil pump generates the fluid working pressure
needed for operation and lubrication. The pump is
J30RH/32RH AUTOMATIC TRANSMISSION 21 - 67

30RH/32RH TRANSMISSION DIAGNOSIS
INDEX
page page
Air Pressure Test......................... 74
Analyzing the Road Test.................... 71
Converter Housing Leak Diagnosis............ 75
Converter Stall Test........................ 74
Diagnosis Guides and Charts................ 77
Effects of Incorrect Fluid Level............... 71
Fluid Level Check......................... 70Gearshift Cable/Linkage Adjustment........... 71
General Information....................... 70
Hydraulic Pressure Test.................... 72
Preliminary Diagnosis...................... 70
Road Test............................... 71
Transmission Throttle Valve Cable Adjustment.... 71
GENERAL INFORMATION
Automatic transmission problems are generally a
result of:
²poor engine performance
²incorrect fluid level
²incorrect throttle valve cable adjustment
²incorrect band adjustment
²incorrect hydraulic control pressure adjustments
²hydraulic component malfunctions
²mechanical component malfunctions.
Begin diagnosis by checking the easily accessible
items such as fluid level, fluid condition and control
linkage adjustment. A road test will determine if fur-
ther diagnosis is necessary.
Procedures outlined in this section should be per-
formed in the following sequence to realize the most
accurate results:
²Preliminary diagnosis
²Check fluid level and condition
²Check control linkage Adjustment
²Road test
²Stall test
²Hydraulic pressure test
²Air pressure tests
²Leak test
²Analyze test results and consult diagnosis charts
PRELIMINARY DIAGNOSIS
Two basic procedures are required. One procedure
for vehicles that are driveable and an alternate pro-
cedure for disabled vehicles (will not back up or move
forward).
Vehicle Is Driveable
(1) Check fluid level and condition.
(2) Adjust throttle cable and gearshift linkage if
complaint was based on delayed, erratic, or harsh
shifts.
(3) Road test vehicle and note transmission operat-
ing characteristics.(4) Perform stall test if complaint is based on slug-
gish, low speed acceleration or abnormal throttle
opening needed to maintain normal speeds with
properly tuned engine.
(5) Perform hydraulic pressure tests.
(6) Perform air pressure test to check clutch-band
operation.
Vehicle Is Disabled
(1) Check fluid level and condition.
(2) Check for broken, disconnected throttle linkage.
(3) Check for cracked, leaking cooler lines, or loose,
missing pressure port plugs.
(4) Raise vehicle, start engine, shift transmission
into gear and note following:
(a) If propeller shafts turn but wheels do not,
problem is with differential or axle shafts.
(b) If propeller shafts do not turn and transmis-
sion is noisy, stop engine. Remove oil pan, and
check for debris. If pan is clear, remove transmis-
sion and check for damaged drive plate, converter,
oil pump or input shaft.
(c) If propeller shafts do not turn and transmis-
sion is not noisy, perform hydraulic pressure test to
determine if problem is a hydraulic or mechanical.
FLUID LEVEL CHECK
Transmission fluid level should be checked monthly
under normal operation. If the vehicle is used for
trailer towing or similar heavy load hauling, check
fluid level and condition weekly.
Fluid level is checked with the engine running at
curb idle speed, the transmission in Neutral and the
transmission fluid at normal operating temperature.
FLUID LEVEL CHECK PROCEDURE
(1) Transmission fluid must be at normal operating
temperature for accurate fluid level check. Drive ve-
hicle if necessary to bring fluid temperature up to
normal hot operating temperature of 82ÉC (180ÉF).
(2) Position vehicle on level surface. This is ex-
tremely important for accurate fluid level check.
(3) Start and run engine at curb idle speed.
21 - 70 30RH/32RH TRANSMISSION DIAGNOSISJ

CONVERTER STALL TEST
Stall testing involves determining maximum engine
rpm obtainable at full throttle with the rear wheels
locked and the transmission in D range. This test
checks the holding ability of the converter overrun-
ning clutch and both of the transmission clutches.
When stall testing is completed, refer to the Stall
Speed Specifications chart and Stall Speed Diagnosis
guides.
WARNING: NEVER ALLOW ANYONE TO STAND IN
FRONT OF THE VEHICLE DURING A STALL TEST.
ALWAYS BLOCK THE FRONT WHEELS AND APPLY
THE SERVICE AND PARKING BRAKES DURING
THE TEST.
STALL TEST PROCEDURE
(1) Connect tachometer to engine.
(2) Check and adjust transmission fluid level.
(3) Start and run engine until transmission fluid
reaches normal operating temperature.
(4) Block front wheels.
(5) Fully apply service and parking brakes.
(6) Open throttle completely and record maximum
engine rpm registered on tachometer. It will take
from 3 to 10 seconds to reach maximum rpm. How-
ever, once maximum rpm has been achieved,do not
hold wide open throttle for more than 5 sec-
onds.
CAUTION: Stalling the converter causes a rapid in-
crease in fluid temperature. To avoid fluid overheat-
ing, hold wide open throttle for no more than 5
seconds after reaching peak rpm. In addition, if
more than one stall test is required, run the engine
at 1000 rpm with the transmission in Neutral for at
least 20 seconds to cool the fluid.
(7) Stall speeds should be in 1700-2150 rpm range.
CAUTION: If engine exceeds 2150 rpm, release ac-
celerator pedal immediately as transmission clutch
slippage is occurring.
(8) Shift transmission into Neutral. Run engine for
20-30 seconds at 1000 rpm to cool fluid. Then stop
engine, shift transmission into Park and release
brakes.
(9) Refer to Stall Test Diagnosis.
STALL TEST DIAGNOSIS
Stall Speed Too Low
Low stall speeds with a properly tuned engine in-
dicate a torque converter overrunning clutch prob-
lem. The condition should be confirmed by road
testing prior to converter replacement.The converter overrunning clutch is slipping when
stall speeds are 250 to 350 rpm below specified min-
imum.
A converter overrunning clutch failure will result
in sluggish acceleration in all speed ranges. It will
also require greater than normal throttle opening to
maintain cruising speeds.
Stall Speed Too High
If stall speed exceeds 2150 rpm, transmission
clutch slippage is occurring.
Stall Speed Normal But Acceleration Is Sluggish
If stall speeds are within specified range but abnor-
mal throttle opening is required for acceleration, or
to maintain cruise speeds, the converter overrunning
clutch is seized. The torque converter will have to be
replaced.
Converter Noise During Test
A whining noise caused by fluid flow is normal dur-
ing a stall test. However, loud metallic noises indi-
cate a damaged converter. To confirm that noise is
originating from the converter, operate the vehicle at
light throttle in Drive and Neutral on a hoist and lis-
ten for noise from the converter housing.
AIR PRESSURE TEST
Air pressure testing can be used to check clutch
and band operation with the transmission either in
the vehicle, or on the work bench as a final check af-
ter overhaul.
Air pressure testing requires that the oil pan and
valve body be removed from the transmission.
The servo and clutch apply passages are shown in
Figure 8.
Air Test Procedure
(1) Place one or two fingers on the clutch housing
and apply air pressure through front clutch apply
passage (Fig. 8). Piston movement can be felt and a
soft thud heard as the clutch applies.
(2) Place one or two fingers on the clutch housing
and apply air pressure through rear clutch apply
passage (Fig. 8). Piston movement can be felt and a
soft thud heard as the clutch applies.
(3) Apply air pressure to the front servo apply pas-
sage. The servo rod should extend and cause the
band to tighten around the drum. Spring tension
should release the servo when air pressure is re-
moved.
(4) Apply air pressure to the rear servo apply pas-
sage. The servo rod should extend and cause the
band to tighten around the drum. Spring tension
should release the servo when air pressure is re-
moved.
21 - 74 30RH/32RH TRANSMISSION DIAGNOSISJ

CONVERTER HOUSING LEAK DIAGNOSIS
Two items must be established when diagnosing
leaks from the converter housing area. First, it must
be verified that a leak condition actually exists. And
second, the true source of the leak must be deter-
mined.
Some suspected converter housing fluid leaks may
not be leaks at all. Residual fluid in the housing, or
excess fluid spilled during factory fill or refill after
repair can be mistaken for a leak. In addition, a rear
main seal leak can also be mistaken for a pump seal
leak if care is exercised.
Converter housing leaks have several potential
sources. Through careful observation, a leak source
can be identified before removing the transmission
for repair.
Pump seal leaks tend to move along the drive hub
and onto the rear of the converter. Pump O-ring or
pump body leaks follow the same path as a seal leak
(Fig. 9).
Pump vent or pump attaching bolt leaks are gener-
ally deposited on the inside of the converter housing
and not on the converter itself (Fig. 9).
Pump seal or gasket leaks usually travel down the
inside of the converter housing.
Front band lever pin plug leaks are generally de-
posited on the housing and not on the converter.
LEAK DIAGNOSIS PROCEDURE
(1) Raise the rear of the vehicle and allow accumu-
lated fluid to drain out of the converter housing.
(2) Check and adjust the transmission fluid level.
(3) Raise the vehicle. Remove the converter hous-
ing dust cover and wipe as much fluid as possible
from the converter housing.(4) Fabricate a test probe (Fig. 10). Then attach
the probe to the converter housing with one of the
dust shield bolts (Fig. 10).
(5) Have a helper run the engine at 2500 rpm
(with the transmission in Neutral) for two minutes;
then stop the engine.
(6) Inspect the test probe and converter housing. If
a leak is evident, note the color of the fluid. Trans-
mission fluid is red. Engine oil ranges in color from
brown to green, or to black when the oil is dirty.
(7) If the probe upper surface is dry, the converter
and seal are not at fault. A path of fluid across the
probe upper surface indicates a converter or seal
leak. Fluid leakingunderthe probe is coming from
the pump housing area (Fig. 11).
(8) Fluid leaking under the probe could be from
the: pump seal and/or bushing, pump vent, kickdown
lever shaft access plug, pump bolts, or porous spots
in the pump body or transmission case (Fig. 11).
(9) If porous spots in the transmission case or
pump body are the suspected leak source, pressurize
the transmission as described in Leak Testing With
Air Pressure.
Fig. 8 Air Pressure Test Passages
Fig. 9 Typical Converter Housing Leak Paths
Fig. 10 Leak Test Probe
J30RH/32RH TRANSMISSION DIAGNOSIS 21 - 75

(4) Apply thick soapy water solution to suspected
leak areas.
CAUTION: The recommended test pressure is 8 psi.
The maximum allowable test pressure is 10 psi. Do
not exceed specified test pressure.
(5) Pressurize transmission to 8 psi with air pump.
(6) Observe suspected leak areas. Air bubbles ap-
pearing in soapy water solution indicate leak points.
(7) Remove test tools and plugs after test comple-
tion and make necessary repairs as described in Leak
Correction procedure.
CONVERTER HOUSING AREA LEAK
CORRECTION
(1) Remove converter.
(2) Tighten front band adjusting screw until band
is tight around clutch retainer. This prevents
clutches from coming out when oil pump is removed.
(3) Remove oil pump and seal. Inspect pump hous-
ing drainback and vent holes for obstructions. Clear
holes with solvent and wire.(4) Inspect pump bushing and converter hub. If
bushing is scored, replace it. If converter hub is
scored, either polish it with crocus cloth or replace
converter if scoring is severe.
(5) Install new pump seal, O-ring, gasket, bushing.
Replace oil pump if cracked, porous or damaged in
any way.
(6) Loosen kickdown lever pin plug two turns. Ap-
ply Permatex No. 2 or equivalent to plug threads and
tighten plug to 17 Nzm (150 in-lbs) torque.
(7) Adjust front band.
(8) Lubricate pump seal and converter hub with
transmission fluid or petroleum jelly and install con-
verter.
(9) Install transmission.
(10) Install converter housing dust shield and
lower vehicle.
DIAGNOSIS GUIDES AND CHARTS
The diagnosis charts provide additional reference
for transmission and converter clutch diagnosis.
The hydraulic flow charts outline fluid flow and hy-
draulic circuitry. Circuit operation is provided for all
gear ranges. Normal working pressures are also sup-
plied for each of the various gear ranges.
Fig. 15 Vent Plug And Hub Seal Cup Installation
Fig. 16 Pressurizing Transmission
J30RH/32RH TRANSMISSION DIAGNOSIS 21 - 77

on transmission. Tighten pan bolts to 17 Nzm (150 in.
lbs.) torque.
(7) Lower vehicle.
(8) Refill transmission with Mopar ATF Plus.
VALVE BODY REMOVAL
(1) Raise vehicle.
(2) Remove oil pan and drain fluid.
(3) Disconnect gearshift and throttle linkage at
transmission levers.
(4) Loosen clamp bolts and remove throttle and
manual valve levers from manual valve shaft.
(5) Disconnect park/neutral position switch wires
and remove switch and switch seal.
(6) Remove valve body oil filter.
(7) Remove valve body attaching screws. Lower
valve body slightly and remove accumulator piston
and spring (Fig. 11). Rotate valve body down and
away from case. Pull it forward to disengage park
rod and remove valve body.
(8) Position valve body on bench or on repair stand
for disassembly, cleaning and inspection (Fig. 12).
VALVE BODY SERVICE
The valve body can be disassembled for cleaning
and inspection of the individual components. Valve
body service procedures are detailed in the overhaul
section.
The only serviceable valve body components are:
²park lock rod and E-clip
²switch valve and spring
²pressure adjusting screw bracket
²throttle valve lever
²manual lever
²manual lever shaft seal, washer, E-clip and detent
ball
²fluid filter
²converter clutch solenoid
The remaining valve body components are serviced
only as part of a complete valve body assembly.
VALVE BODY INSTALLATION
(1) Place valve body manual lever in low (1 posi-
tion) so park lock rod can be installed in sprag.
(2) Position park sprag with screwdriver to ease
lock rod installation and engagement.
(3) Install new seals on accumulator piston if nec-
essary and install piston in case. A small amount of
petroleum jelly can be used to hold piston in place.
(4) Lubricate shaft of manual lever and lip of shaft
seal with petroleum jelly.
(5) Raise valve body and align park rod with case
opening and park sprag. Then push rod end through
opening and past sprag. Rotate propeller shaft if nec-
essary.
(6) Position accumulator spring on transfer plate.
Fig. 10 Oil Filter Screw Locations
Fig. 11 Accumulator Piston And Spring
Fig. 12 Valve Body Assembly
21 - 104 30RH/32RH IN-VEHICLE SERVICEJ

CONNECTING COOLER LINES AND FITTINGS
(ALL TYPES)
(1) Wipe cooler line and fitting clean with shop
towel.
(2) Insert cooler line into fitting. Then push line
inward until retainer or insert secures line. A snap or
click sound will be heard when the insert tabs or re-
tainer clip seats behind the cooler line flange.
(3)Pull outward on cooler lines/fittings to
verify they are properly secured.
CAUTION: The wire retainer clips or insert release
tabs secure the cooler lines. If the clips or tabs are
deformed, distorted, or not fully seated, normal
fluid pressure could unseat the lines resulting in
fluid loss and transmission damage. Be very sure
the cooler lines are firmly secured as described in
step (3).
CONVERTER DRAINBACK CHECK VALVE SERVICE
The converter drainback check valve is located in
the cooler outlet (pressure) line near the radiator
lower tank. The valve prevents fluid drainback when
the vehicle is parked for lengthy periods. The valve
check ball is spring loaded and has an opening pres-
sure of approximately 2 psi. Refer to the cooler flow
test procedure for valve testing.
The valve is serviced as an assembly; it is not re-
pairable. Do not clean the valve if restricted, or con-
taminated by sludge, or debris. If the valve fails, or if
a transmission malfunction occurs that generates
sludge and/or clutch particles and metal shavings,
the valve must be replaced.
The valve must be removed whenever the cooler
and lines are reverse flushed. The valve can be flow
tested when necessary. The procedure is exactly the
same as for flow testing a cooler.
If the valve is restricted, installed backwards, or in
the wrong line, it will cause an overheat condition
and possible transmission failure.
CAUTION: The drainback valve is a one-way valve.
As such, it must be properly oriented in terms of
flow direction. In addition, the valve must only beinstalled in the pressure line. Otherwise flow will be
blocked causing overheat and eventual transmis-
sion failure.
TRANSMISSION COOLER FLOW TESTING
The transmission main and auxiliary coolers, plus
the drainback valve, should be flow tested whenever
fluid overheating is noted.
Restricted flow caused by contamination, or a
cooler malfunction, reduces lubrication fluid flow
throughout the transmission. This can result in fluid
overheating, fluid breakdown, bushing wear, shift
problems and component failure.
Normal color of transmission fluid varies from
bright red, to light pink. Fluid overheating is indi-
cated when fluid color ranges from orange-brown to
black, and the fluid smells burned, or contains
sludge.
CAUTION: If a transmission malfunction contami-
nates the fluid with clutch disc and metal particles,
the cooler and lines must be reverse flushed thor-
oughly. Flushing will prevent sludge and particles
from flowing back into the transmission and con-
verter after repair.
Cooler flow is tested by measuring the amount of
fluid pumped through the cooler in a specified time
by the transmission oil pump.The same flow test
procedure is used for the drainback valve, main
cooler, and auxiliary cooler.
Cooler And Drainback Valve Flow Test Procedure
(1) Test flow throughdrainback valveas follows:
(a) Add extra quart of ATF Plus to transmission.
(b) Disconnect pressure line at radiator fitting, or
at drainback valve and position hose or valve end
in one quart test container.
(c) Shift transmission into neutral, run engine at
idle speed for 20 seconds, and note flow from valve.
Use stopwatch to check test time.
(d) Replace drainback valve if flow is less than
one quart in 20 seconds, is intermittent, or does
not flow at all.
(e) Connect pressure hose to radiator fitting and
proceed to cooler flow test.
(2) Test flow throughmain cooleras follows:
(a) Disconnect cooler return (rear) line at trans-
mission and place it in one quart test container.
(b) Add extra quart of fluid to transmission.
(c) Shift transmission into neutral, run engine at
idle speed for 20 seconds, and note flow from valve.
Use stopwatch to check test time.
(d) Replace cooler if fluid flow is less than one
quart in 20 seconds, is intermittent, or does not
flow at all.
Fig. 33 New Style Fitting Insert (On Cooler Line)
J30RH/32RH IN-VEHICLE SERVICE 21 - 113