2002 CHRYSLER CARAVAN oil pressure

TORQUE SPECIFICATIONS
Description N´m Ft. Lbs. In. Lbs.
Bolt, Differential Bearing Retainer-to-Case 34 Ð 300
Bolt, Differential Cover-to-Case 19 Ð 165
Bolt, Differential Ring Gear-to-Case 95 70 Ð
Bolt, Extension Housing-to-Case 28 Ð 250
Bolt, Drive Plate-to-Crankshaft 95 70 Ð
Bolt, Drive Plate-to-Torque Converter 68 50 Ð
Bolt, Governor-to-Support 7 Ð 60
Bolt, Output Gear Strap 23 17 Ð
Bolt, Oil Pan-to-Case 19 Ð 165
Bolt, Oil Pump-to-Case 31 Ð 275
Bolt, Park Rod Support-to-Case 28 Ð 250
Bolt, Reaction Support-to-Pump Body 28 Ð 250
Bolt, Sprag Retainer-to-Case 28 Ð 250
Bolt, Starter Motor-to-Transaxle 54 40 Ð
Bolt, Transaxle Case-to-Engine Block 95 70 Ð
Bolt, Transfer Gear Cover-to-Case 19 Ð 165
Bolt, Transfer Gear Strap 23 17 Ð
Bolt, Valve Body-to-Case 12 Ð 105
Fitting, Transaxle Oil Cooler-to-Case 7 Ð 60
Screw, Fluid Filter 5 Ð 45
Screw, Cooler Bypass Valve-to-Transfer Plate 5 Ð 40
Screw, Governor Counterweight 28 Ð 250
Screw, Manual Valve Lever-to-Shaft 12 Ð 105
Screw, Speedo Adapter-to-Extension Housing 7 Ð 60
Screw, Valve Body-to-Transfer Plate 5 Ð 45
Nut, Kickdown Band Adjuster Lock 47 35 Ð
Nut, Output Gear-to-Shaft 271 200 Ð
Nut, Reverse Band Adjuster Lock 14 Ð 125
Nut, Transfer Gear-to-Shaft 271 200 Ð
Plug, Pressure Tap 5 Ð 45
Plug, Rear Band Lever Pivot Shaft 7 Ð 60
Switch, Park/Neutral 34 25 Ð
21 - 74 31TH AUTOMATIC TRANSAXLERS
31TH AUTOMATIC TRANSAXLE (Continued)
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SPECIAL TOOLS
31TH AUTOMATIC TRANSAXLE
Adapter Blocks C-293±45
Adapter Blocks C-293±52
Puller Press C-293±PA
Pressure Gauge (High) C-3293SP
Dial Indicator C-3339
Spring Compressor C-3575-A
Band Adjusting Adapter C-3705
Oil Pump Puller C-3752
Throttle Setting Gauge C-3763
Seal Puller C-3981B
RS31TH AUTOMATIC TRANSAXLE21-75
31TH AUTOMATIC TRANSAXLE (Continued)
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CLUTCH - FRONT
DESCRIPTION
The front clutch assembly (Fig. 119) is composed of
the front clutch retainer, pressure plate, clutch
plates, driving discs, piston, piston return spring,
return spring retainer, and snap-rings. The front
clutch is the forward-most component in the trans-
mission geartrain and is directly behind the oil
pump. It is considered a driving component.
NOTE: The number of discs and plates may vary
with each engine and vehicle combination.
OPERATION
To apply the clutch, pressure is applied between
the clutch retainer and piston. The fluid pressure is
provided by the oil pump, transferred through the
control valves and passageways, and enters the
clutch through the hub of the reaction shaft support.
With pressure applied between the clutch retainer
and piston, the piston moves away from the clutch
retainer and compresses the clutch pack. This action
applies the clutch pack, allowing torque to flow
through the input shaft into the driving discs, and
into the clutch plates and pressure plate that are
lugged to the clutch retainer. The waved snap-ring is
used to cushion the application of the clutch pack. In
some transmissions, the snap-ring is selective and
used to adjust clutch pack clearance.
When pressure is released from the piston, the
spring returns the piston to its fully released position
and disengages the clutch. The release spring also
helps to cushion the application of the clutch assem-
bly. When the clutch is in the process of being
released by the release spring, fluid flows through a
vent and one-way ball-check-valve located in the
clutch retainer. The check-valve is needed to elimi-
nate the possibility of plate drag caused by centrifu-
gal force acting on the residual fluid trapped in the
clutch piston retainer.
DISASSEMBLY
(1) Remove front clutch waved snap ring using a
suitable screwdriver (Fig. 114).
(2) Remove waved snap ring and reaction plate
(Fig. 115).
Fig. 114 Front Clutch Waved Snap Ring
1 - WAVED SNAP RING
2 - SCREWDRIVER
3 - FRONT CLUTCH ASSEMBLY
Fig. 115 Thick Steel Plate and Waved Snap Ring
1 - WAVED SNAP RING
2 - THICK STEEL PLATE
3 - FRONT CLUTCH RETAINER
21 - 82 31TH AUTOMATIC TRANSAXLERS
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(5) Using feeler gauge, measure front clutch clear-
ance (Fig. 125).Front clutch clearance should be
within 1.27-2.79 mm (0.050-0.110 in.) and is not
adjustable.
CLUTCH - REAR
DESCRIPTION
The rear clutch assembly (Fig. 132) is composed of
the input shaft, rear clutch retainer, pressure plate,
clutch plates, driving discs, piston, Belleville spring,
and snap-rings. The Belleville spring acts as a lever
to multiply the force applied on to it by the apply pis-
ton. The increased apply force on the rear clutch
pack, in comparison to the front clutch pack, is
needed to hold against the greater torque load
imposed onto the rear pack. The rear clutch is
directly behind the front clutch and is considered a
driving component.
NOTE: The number of discs and plates may vary
with each engine and vehicle combination.
OPERATION
To apply the clutch, pressure is applied between
the clutch retainer and piston. The fluid pressure is
provided by the oil pump, transferred through the
control valves and passageways, and enters the
clutch through the hub of the reaction shaft support.
With pressure applied between the clutch retainer
and piston, the piston moves away from the clutch
retainer and compresses the clutch pack. This action
applies the clutch pack, allowing torque to flow
through the input shaft into the driving discs, and
into the clutch plates and pressure plate that are
lugged to the clutch retainer. The waved snap-ring is
used to cushion the application of the clutch pack. In
some transmissions, the snap-ring is selective and
used to adjust clutch pack clearance.
When pressure is released from the piston, the
spring returns the piston to its fully released position
and disengages the clutch. The release spring also
helps to cushion the application of the clutch assem-
bly. When the clutch is in the process of being
released by the release spring, fluid flows through a
vent and one-way ball-check-valve located in the
clutch retainer. The check-valve is needed to elimi-
nate the possibility of plate drag caused by centrifu-
gal force acting on the residual fluid trapped in the
clutch piston retainer.
Fig. 124 Front Clutch Waved Snap Ring
1 - WAVED SNAP RING
2 - SCREWDRIVER
3 - FRONT CLUTCH ASSEMBLY
Fig. 125 Measuring Front Clutch Plate Clearance
1 - FEELER GAUGE
2 - FRONT CLUTCH ASSEMBLY
21 - 86 31TH AUTOMATIC TRANSAXLERS
CLUTCH - FRONT (Continued)
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FLUID
STANDARD PROCEDURE
STANDARD PROCEDURE - FLUID LEVEL AND
CONDITION CHECK
NOTE: The transmission and differential sump have
a common oil sump with a communicating opening
between the two.
FLUID LEVEL CHECK
The torque converter fills in both the P Park and N
Neutral positions. Place the selector lever in P Park
to be sure that the fluid level check is accurate.The
engine should be running at idle speed for at
least one minute, with the vehicle on level
ground. This will assure complete oil level sta-
bilization between differential and transmis-
sion.The fluid should be at normal operating
temperature (approximately 82 C. or 180 F.). The
fluid level is correct if it is in the HOT region (cross-
hatched area) on the fluid level indicator (Fig. 165).
Low fluid level can cause a variety of conditions
because it allows the pump to take in air along with
the fluid. As in any hydraulic system, air bubbles
make the fluid spongy, therefore, pressures will be
low and build up slowly.
Improper filling can also raise the fluid level too
high. When the transaxle has too much fluid, the
gears churn up foam and cause the same conditions
which occur with a low fluid level.
In either case, the air bubbles can cause overheat-
ing, fluid oxidation, and varnishing. This can inter-
fere with normal valve, clutch, and servo operation.
Foaming can also result in fluid escaping from thetransaxle dipstick where it may be mistaken for a
leak.
FLUID CONDITION
Along with fluid level, it is important to check the
condition of the fluid. MopartATF+4 (Automatic
Transmission Fluid-Type 9602) when new is red in
color. The ATF is dyed red so it can be identified from
other fluids used in the vehicle such as engine oil or
antifreeze. The red color is not permanent and is not
an indicator of fluid condition. As the vehicle is
driven, the ATF will begin to look darker in color and
may eventually become brown.This is normal.
ATF+4 also has a unique odor that may change with
age. Consequently,odor and color cannot be used
to indicate the fluid condition, or the need for a
fluid change.
After the fluid has been checked, seat the dipstick
fully to seal out water and dirt.
STANDARD PROCEDURE - FLUID AND FILTER
CHANGE
NOTE: For the recommended maintenance (fluid/fil-
ter change) intervals for this transaxle, (Refer to
LUBRICATION & MAINTENANCE/MAINTENANCE
SCHEDULES - DESCRIPTION)
NOTE: Only fluids of the type labeled MoparTATF+4
(Automatic Transmission Fluid) Type 9602 should
be used. A filter change should be made at the time
of the transmission oil change. The magnet (on the
inside of the oil pan) should also be cleaned with a
clean, dry cloth.
NOTE: If the transaxle is disassembled for any rea-
son, the fluid and filter should be changed.
FLUID/FILTER SERVICE (RECOMMENDED)
(1) Raise vehicle on a hoist. Place a drain con-
tainer with a large opening, under transaxle oil pan.
(2) Loosen pan bolts and tap the pan at one corner
to break it loose allowing fluid to drain, then remove
the oil pan.
(3) Remove oil filter-to-valve body screws (Fig.
166).
(4) Remove oil filter and gasket (Fig. 167).
(5) Install a new filter and gasket (Fig. 167).
(6) Clean the oil pan and magnet. Reinstall pan
using new MopartSilicone Rubber Adhesive Sealant.
Torque oil pan bolts to 19 N´m (165 in. lbs.).
(7) Pour four quarts of MopartATF+4 (Automatic
Transmission Fluid-Type 9602) through the dipstick
opening.
Fig. 165 Fluid Level Indicator Markings
1 - TRANSAXLE DIPSTICK
RS31TH AUTOMATIC TRANSAXLE21-99
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SERVO - KICKDOWN
DESCRIPTION
The kickdown servo (Fig. 196) consists of a two-
land piston with an inner piston, a piston rod and
guide, and a return spring. The dual-land piston uses
seal rings on its outer diameters and an O-ring for
the inner piston.
OPERATION
The application of the piston is accomplished by
applying pressure between the two lands of the pis-
ton. The pressure acts against the larger lower land
to push the piston downward, allowing the piston rod
to extend though its guide against the apply lever.
Release of the servo at the 2-3 upshift is accom-
plished by a combination of spring and line pressure,
acting on the bottom of the larger land of the piston.
The small piston is used to cushion the application of
the band by bleeding oil through a small orifice in
the larger piston. The release timing of the kickdown
servo is very important to obtain a smooth but firm
shift. The release has to be very quick, just as the
front clutch application is taking place. Otherwise,
engine runaway or a shift hesitation will occur. To
accomplish this, the band retains its holding capacity
until the front clutch is applied, giving a small
amount of overlap between them.
DISASSEMBLY
(1) Remove kickdown servo snap ring (Fig. 197).
(2) Remove kickdown servo rod guide and snap
ring (Fig. 198).
Fig. 196 Front Servo
1 - VENT
2 -PISTON ROD
3 - PISTON
4 - SPRING
5 - RELEASE PRESSURE
6 - APPLY PRESSURE
Fig. 197 Kickdown Servo Snap Ring
1 - SNAP RING
2 - SNAP RING PLIERS
3 - ACCUMULATOR PLATE
4 - KICKDOWN LEVER
5 - KICKDOWN PISTON ROD GUIDE
Fig. 198 Kickdown Servo Rod Guide and Snap Ring
1 - SNAP RING
2 - ACCUMULATOR PLATE
3 - RETURN SPRING
4 - O-RING
5 - PISTON ROD GUIDE
RS31TH AUTOMATIC TRANSAXLE21 - 111
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valve or plug edges. Squareness of these edges is
vitally important. These edges prevent foreign matter
from lodging between the valves, plugs and bore.
INSPECTION
Inspect the throttle and manual valve levers and
shafts. Do not attempt to straighten a bent shaft or
correct a loose lever. Replace these components if
worn, bent, loose or damaged in any way.
Inspect all of the valve body mating surfaces for
scratches, nicks, burrs, or distortion. Use a straight-
edge to check surface flatness. Minor scratches may
be removed with crocus cloth using only very light
pressure.
Inspect the valves and plugs for scratches, burrs,
nicks, or scores. Also inspect the coating on the alu-
minum valves and plugs. If the coating is damaged
or worn through, the valve (or valve body) should be
replaced.
Inspect all the valve and plug bores in the valve
body. Use a penlight to view the bore interiors.
Replace the valve body if any bores are distorted or
scored. Inspect all of the valve body springs. The
springs must be free of distortion, warpage or broken
coils.
Trial fit each valve and plug in its bore to check
freedom of operation. When clean and dry, the valves
and plugs should drop freely into the bores. Valve
body bores do not change dimensionally with use. If
the valve body functioned correctly when new, it will
continue to operate properly after cleaning and
inspection. It should not be necessary to replace a
valve body assembly unless it is damaged in han-
dling.
ASSEMBLY
(1) Install shift/shuttle valves and springs as
shown in (Fig. 320).
(2) Install torque converter clutch solenoid, spring,
and plug as shown in (Fig. 319).
(3) Install governor plugs as shown in (Fig. 318).
(4) Install pressure regulator and manual control
springs and valves as shown in (Fig. 317).
(5) Install pressure regulator spring retainer/ad-
justing screw bracket (Fig. 321).
(6) Install manual valve from valve body (Fig.
322).
Fig. 321 Pressure Regulator and Adjusting Screw
Bracket
1 - SCREWDRIVER HANDLE
2 - PRESSURE REGULATOR SPRING RETAINER AND
ADJUSTING SCREW BRACKET
3 - VALVE BODY
4 - SCREWS
Fig. 322 Install Manual Valve
1 - MANUAL VALVE
2 - VALVE BODY
RS31TH AUTOMATIC TRANSAXLE21 - 155
VALVE BODY (Continued)
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(8) Install and torque oil pan-to-transaxle bolts
(Fig. 339) to 19 N´m (165 in. lbs.).
(9) Lower vehicle.
(10) Connect torque converter clutch solenoid.
(11) Connect gearshift cable to manual valve lever.
(12) Connect throttle valve cable to throttle valve
lever at transaxle.
(13) Connect battery negative cable.
ADJUSTMENTS
HYDRAULIC CONTROL PRESSURE
ADJUSTMENTS
LINE PRESSURE
An incorrect throttle pressure setting will cause incor-
rect line pressure readings even though line pressure
adjustment is correct. Always inspect and correct throttle
pressure adjustment before adjusting the line pressure.
The approximate adjustment for line pressure is 1-5/16
inches, measured from valve body to inner edge of adjust-
ing nut. However, due to manufacturing tolerances, the
adjustment can be varied to obtain specified line pres-
sure.
The adjusting screw may be turned with an Allen
wrench. One complete turn of adjusting screw
changes closed throttle line pressure approximately
1-2/3 psi. Turning adjusting screw counterclockwise
increases pressure, and clockwise decreases pressure.
THROTTLE PRESSURE
Throttle pressures cannot be tested accurately;
therefore, the adjustment should be measured if a
malfunction is evident.
(1) Insert gauge pin of Tool C-3763 between the
throttle lever cam and kickdown valve.(2) By pushing in on tool, compress kickdown
valve against its spring so throttle valve is com-
pletely bottomed inside the valve body.
(3) While compressing spring, turn throttle lever
stop screw with adapter C-4553. Turn until head of
screw touches throttle lever tang, with throttle lever
cam touching tool and throttle valve bottomed. Be
sure adjustment is made with spring fully com-
pressed and valve bottomed in the valve body.
VEHICLE SPEED SENSOR/
PINION GEAR
REMOVAL
(1)Remove harness connector from sensor (Fig. 340).
Be sure weather seal stays on harness connector.
(2) Remove bolt securing the sensor in the exten-
sion housing (Fig. 340) .
(3) Carefully pull sensor and pinion gear assembly
out of extension housing.
(4) Remove pinion gear from sensor (Fig. 340) .
(5) Inspect pinion gear for damage (missing teeth,
etc.) and replace as necessary.
NOTE: When removing vehicle speed sensor for
any reason, a new o-ring MUST be used.
INSTALLATION
(1) Install vehicle speed sensor and pinion gear to
extension housing with new o-ring (Fig. 340).
(2) Install bolt and torque to 7 N´m (60 in. lbs.).
(3) Connect connector.
(4) Lower vehicle.
Fig. 339 Transaxle Oil Pan Bolts
1 - TRANSAXLE OIL PAN
2 - OIL PAN BOLTS
Fig. 340 Vehicle Speed Sensor Removal/Installation
1 - CONNECTOR
2 - SPEEDO PINION
3 - O-RING
4 - SENSOR
21 - 160 31TH AUTOMATIC TRANSAXLERS
VALVE BODY (Continued)
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