STANDARD PROCEDURE - OIL PUMP VOLUME
CHECK
Measuring the oil pump output volume will deter-
mine if sufficient oil flow to the transmission oil
cooler exists, and whether or not an internal trans-
mission failure is present.
Verify that the transmission fluid is at the proper
level. Refer to the Fluid Level Check procedure in
this section. If necessary, fill the transmission to the
proper level with MopartATF +4, type 9602, Auto-
matic Transmission Fluid.
(1) Disconnect theTo coolerline at the cooler
inlet and place a collecting container under the dis-
connected line.
CAUTION: With the fluid set at the proper level,
fluid collection should not exceed (1) quart or inter-
nal damage to the transmission may occur.
(2) Run the engineat curb idle speed, with the
shift selector in neutral.
(3) If one quart of transmission fluid is collected in
the container in 20 seconds or less, oil pump flow vol-
ume is within acceptable limits. If fluid flow is inter-
mittent, or it takes more than 20 seconds to collect
one quart of fluid, refer to the Hydraulic Pressure
tests in this section for further diagnosis.
(4) Re-connect theTo coolerline to the transmis-
sion cooler inlet.
(5) Refill the transmission to proper level.
DISASSEMBLY
(1) Remove seal ring from housing and reaction
shaft support (Fig. 98).
(2) Mark pump housing and support assembly for
alignment reference.
(3) Remove bolts attaching pump body to support
(Fig. 99).(4) Separate support from pump housing (Fig.
100).
Fig. 100 Separating Pump Housing From Reaction
Shaft Support
1 - REACTION SHAFT SUPPORT
2 - PUMP HOUSING
Fig. 98 Removing Pump Seal Ring
1 - PUMP HOUSING SEAL RING
Fig. 99 Pump Support Bolts
1 - REACTION SHAFT SUPPORT
2 - PUMP
BR/BEAUTOMATIC TRANSMISSION - 42RE 21 - 209
OIL PUMP (Continued)
(5) Remove inner and outer gears from reaction
shaft support (Fig. 101).
(6) If pump seal was not removed during transmis-
sion disassembly, remove seal with punch and ham-
mer.
(7) Remove front clutch thrust washer from sup-
port hub (Fig. 102).
OIL PUMP BUSHING REPLACEMENT
(1) Remove pump bushing with Tool Handle
C-4171 and Bushing Remover SP-3551 from Tool Set
C-3887-J (Fig. 103).
(2) Install new pump bushing with Tool Handle
C-4171 and Bushing Installer SP-5117 (Fig. 103).
Bushing should be flush with pump housing bore.
(3) Stake new pump bushing in two places with
blunt punch (Fig. 104). Remove burrs from stake
points with knife blade afterward.
Fig. 101 Pump Gear Removal
1 - REACTION SHAFT SUPPORT
2 - INNER GEAR
3 - OUTER GEAR
Fig. 102 Support Hub Thrust Washer
1 - BUSHING
2 - REACTION SHAFT SUPPORT
3 - THRUST WASHER
4 - HUB
Fig. 103 Removing Oil Pump Bushing
1 - SPECIAL TOOL C-4171
2 - SPECIAL TOOL SP-3551
3 - BUSHING
4 - SPECIAL TOOL SP-5117
5 - BUSHING
6 - SPECIAL TOOL C-4171
7 - PUMP HOUSING
Fig. 104 Staking Oil Pump Bushing
1 - NARROW BLADE
2 - BLUNT PUNCH
3 - TWO STAKES
21 - 210 AUTOMATIC TRANSMISSION - 42REBR/BE
OIL PUMP (Continued)
REACTION SHAFT SUPPORT BUSHING REMOVAL
(1) Assemble Bushing Remover Tools SP-1191,
3633 and 5324 (Fig. 105). Do not clamp any part of
reaction shaft or support in vise.
(2) Hold Cup Tool SP-3633 firmly against reaction
shaft and thread remover SP-5324 into bushing as
far as possible by hand. Then thread remover tool 3-4
additional turns into bushing with a wrench.
(3) Turn remover tool hex nut down against
remover cup to pull bushing from shaft. Clean all
chips from shaft after bushing removal.
(4) Lightly grip old bushing in vise or with pliers
and back remover tool out of bushing.
(5) Assemble Bushing Installer Tools C-4171 and
SP-5325 (Fig. 105).
(6) Slide new bushing onto Installer Tool SP-5325.
(7) Position reaction shaft support upright on a
clean smooth surface.
(8) Align bushing in bore. Then tap bushing into
place until Bushing Installer SP-5325 bottoms.
(9) Clean reaction shaft support thoroughly after
installing bushing.
CLEANING
Clean pump and support components with solvent
and dry them with compressed air.
INSPECTION
Check condition of the seal rings and thrust
washer on the reaction shaft support. The seal rings
do not need to be replaced unless cracked, broken, or
severely worn.
Inspect the pump and support components. Replace
the pump or support if the seal ring grooves or
machined surfaces are worn, scored, pitted, or dam-
aged. Replace the pump gears if pitted, worn
chipped, or damaged.
Inspect the pump bushing. Then check the reaction
shaft support bushing. Replace either bushing only if
heavily worn, scored or damaged. It is not necessary
to replace the bushings unless they are actually dam-
aged.
Clearance between outer gear and reaction shaft
housing should be 0.010 to 0.063 mm (0.0004 to
0.0025 in.). Clearance between inner gear and reac-tion shaft housing should be 0.010 to 0.063 mm
(0.0004 to 0.0025 in.). Both clearances can be mea-
sured at the same time by installing the gears in the
pump body and measure pump component clearances
as follows:
(1) Position an appropriate piece of PlastigageŸ
across both gears.
(2) Align the plastigage to a flat area on the reac-
tion shaft housing.
(3) Install the reaction shaft to the pump housing.
(4) Separate the reaction shaft housing from the
pump housing and measure the PlastigageŸ follow-
ing the instructions supplied with it.
Clearance between inner gear tooth and outer gear
should be 0.08 to 0.19 mm (0.0035 to 0.0075 in.).
Measure clearance with an appropriate feeler gauge.
Clearance between outer gear and pump housing
should be 0.10 to 0.19 mm (0.004 to 0.0075 in.). Mea-
sure clearance with an appropriate feeler gauge.
Fig. 105 Replacing Reaction Shaft Support Bushing
1 - SPECIAL TOOL SP-1191
2 - SPECIAL TOOL SP-3633
3 - SPECIAL TOOL C-4171
4 - SPECIAL TOOL SP-5325
5 - REACTION SHAFT
6 - SPECIAL TOOL SP-5324
7 - BUSHING
BR/BEAUTOMATIC TRANSMISSION - 42RE 21 - 211
OIL PUMP (Continued)
ASSEMBLY
(1) Lubricate gear bore in pump housing with
transmission fluid.
(2) Lubricate pump gears with transmission fluid.
(3) Support pump housing on wood blocks (Fig.
106).
(4) Install outer gear in pump housing (Fig. 106).
Gear can be installed either way (it is not a one-way
fit).
(5) Install pump inner gear (Fig. 107).
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. 108).
Lubricate 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
being installed, spread them only enough for instal-
lation. 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. 109).
(9) Align reaction support on pump housing. Use
alignment marks made at disassembly. Or, rotate
support until bolt holes in support and pump housing
are all aligned (holes are offset for one-way fit).
Fig. 106 Supporting Pump And Installing Outer Gear
1 - OUTER GEAR
2 - PUMP HOUSING
3 - WOOD BLOCKS
Fig. 107 Pump Inner Gear Installation
1 - OUTER GEAR
2 - INNER GEAR
Fig. 108 Hub Seal Ring Position
1 - SEAL RINGS
2 - SUPPORT HUB
Fig. 109 Assembling Reaction Shaft Support And
Pump Housing
1 - PUMP HOUSING
2 - REACTION SHAFT SUPPORT
21 - 212 AUTOMATIC TRANSMISSION - 42REBR/BE
OIL PUMP (Continued)
(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 N´m (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. 110). 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.
OUTPUT SHAFT FRONT
BEARING
REMOVAL
(1) Remove overdrive unit from the vehicle.
(2) Remove overdrive geartrain from housing.
(3) Remove snap-ring holding output shaft front
bearing to overdrive geartrain. (Fig. 111).
(4) Pull bearing from output shaft.
INSTALLATION
(1) Place replacement bearing in position on
geartrain with locating retainer groove toward the
rear.
(2) Push bearing onto shaft until the snap-ring
groove is visible.
(3) Install snap-ring to hold bearing onto output
shaft.(4) Install overdrive geartrain into housing.
(5) Install overdrive unit in vehicle.
OUTPUT SHAFT REAR
BEARING
REMOVAL
(1) Remove overdrive unit from the vehicle. (Refer
to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC/
OVERDRIVE - REMOVAL)
(2) Remove overdrive geartrain from housing.
(3) Remove snap-ring holding output shaft rear
bearing into overdrive housing (Fig. 112).
(4) Using a suitable driver inserted through the
rear end of housing, drive bearing from housing.
INSTALLATION
(1) Place replacement bearing in position in hous-
ing.
(2) Using a suitable driver, drive bearing into
housing until the snap-ring groove is visible.
(3) Install snap-ring to hold bearing into housing
(Fig. 112).
(4) Install overdrive geartrain into housing.
(5) Install overdrive unit in vehicle.
Fig. 110 Pump Oil Seal Installation
1 - PUMP BODY
2 - PUMP SEAL
3 - SPECIAL TOOL C-4193
Fig. 111 Output Shaft Front Bearing
1 - OUTPUT SHAFT FRONT BEARING
2 - SNAP-RING
3 - OUTPUT SHAFT
4 - GROOVE TO REAR
5 - OVERDRIVE GEARTRAIN
BR/BEAUTOMATIC TRANSMISSION - 42RE 21 - 213
OIL PUMP (Continued)
OVERDRIVE CLUTCH
DESCRIPTION
The overdrive clutch (Fig. 113) is composed of the
pressure plate, clutch plates, holding discs, overdrive
piston retainer, piston, piston spacer, and snap-rings.
The overdrive clutch is the forwardmost component
in the transmission overdrive unit and is considered
a holding component. The overdrive piston retainer,piston, and piston spacer are located on the rear of
the main transmission case.
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 piston retainer and piston. The fluid pressure is
provided by the oil pump, transferred through the
control valves and passageways, and enters the
clutch through passages at the lower rear portion of
the valve body area. With pressure applied between
the piston retainer and piston, the piston moves
away from the piston retainer and compresses the
clutch pack. This action applies the clutch pack,
allowing torque to flow through the intermediate
shaft into the overdrive planetary gear set. The over-
drive clutch discs are attached to the overdrive clutch
hub while the overdrive clutch plates, reaction plate,
and pressure plate are lugged to the overdrive hous-
ing. This allows the intermediate shaft to transfer
the engine torque to the planetary gear and overrun-
ning clutch. This drives the planetary gear inside the
annulus, which is attached to the overdrive clutch
drum and output shaft, creating the desired gear
ratio. The waved snap-ring is used to cushion the
application of the clutch pack.
Fig. 113 Overdrive Clutch
1 - REACTION PLATE 2 - PRESSURE PLATE
Fig. 112 Output Shaft Rear Bearing
1 - OUTPUT SHAFT REAR BEARING
2 - OVERDRIVE HOUSING
3 - SNAP-RING
21 - 214 AUTOMATIC TRANSMISSION - 42REBR/BE
OUTPUT SHAFT REAR BEARING (Continued)
(2) Install the overdrive off switch into the connec-
tor (Fig. 117)
(3) Push the overdrive off switch and wiring into
the shift lever.
(4) Install the overdrive off switch retainer onto
the shift lever.
OVERDRIVE UNIT
REMOVAL
(1) Shift transmission into PARK.
(2) Raise vehicle.
(3) Remove transfer case, if equipped.
(4) Mark propeller shaft universal joint(s) and axle
pinion yoke, or the companion flange and flange
yoke, for alignment reference at installation, if necc-
esary.
(5) Disconnect and remove the rear propeller shaft,
if necessary. (Refer to 3 - DIFFERENTIAL & DRIV-
ELINE/PROPELLER SHAFT/PROPELLER SHAFT -
REMOVAL)
(6) Remove transmission oil pan, remove gasket,
drain oil and reinstall pan.
(7) If overdrive unit had malfunctioned, or if fluid
is contaminated, remove entire transmission. If diag-
nosis indicated overdrive problems only, remove just
the overdrive unit.(8) Support transmission with transmission jack.
(9) Remove bolts attaching overdrive unit to trans-
mission (Fig. 118).
CAUTION: Support the overdrive unit with a jack
before moving it rearward. This is necessary to pre-
vent damaging the intermediate shaft. Do not allow
the shaft to support the entire weight of the over-
drive unit.
(10) Carefully work overdrive unit off intermediate
shaft. Do not tilt unit during removal. Keep it as
level as possible.
(11) If overdrive unit does not require service,
immediately insert Alignment Tool 6227-2 in splines
of planetary gear and overrunning clutch to prevent
splines from rotating out of alignment. If misalign-
ment occurs, overdrive unit will have to be disassem-
bled in order to realign splines.
(12) Remove and retain overdrive piston thrust
bearing. Bearing may remain on piston or in clutch
hub during removal.
(13) Position drain pan on workbench.
(14) Place overdrive unit over drain pan. Tilt unit
to drain residual fluid from case.
(15) Examine fluid for clutch material or metal
fragments. If fluid contains these items, overhaul will
be necessary.
(16) If overdrive unit does not require any service,
leave alignment tool in position. Tool will prevent
accidental misalignment of planetary gear and over-
running clutch splines.
Fig. 117 Install the Overdrive Off Switch
1 - GEAR SHIFT LEVER
2 - OVERDRIVE OFF SWITCH WIRING CONNECTOR
3 - OVERDRIVE OFF SWITCH
Fig. 118 Overdrive Unit Bolts
1 - OVERDRIVE UNIT
2 - ATTACHING BOLTS (7)
21 - 216 AUTOMATIC TRANSMISSION - 42REBR/BE
OVERDRIVE OFF SWITCH (Continued)
REAR CLUTCH
DESCRIPTION
The rear clutch assembly (Fig. 215) is composed of
the rear clutch retainer, pressure plate, clutch plates,
driving discs, piston, Belleville spring, and snap-
rings. The Belleville spring acts as a lever to multi-
ply the force applied on to it by the apply piston. The
increased apply force on the rear clutch pack, in com-
parison 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 spring is
used to cushion the application of the clutch pack.
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
Fig. 215 Rear Clutch
1 - PISTON SPRING 10 - TOP PRESSURE PLATE
2 - REAR CLUTCH PISTON 11 - CLUTCH DISCS (4)
3 - CLUTCH PISTON SEALS 12 - BOTTOM PRESSURE PLATE
4 - OUTPUT SHAFT THRUST WASHER (METAL) 13 - WAVE SPRING
5 - INPUT SHAFT SNAP-RING 14 - CLUTCH PLATES (3)
6 - REAR CLUTCH RETAINER 15 - RETAINER SEAL RING
7 - INPUT SHAFT 16 - SHAFT REAR SEAL RING (PLASTIC)
8 - REAR CLUTCH THRUST WASHER (FIBER) 17 - SHAFT FRONT SEAL RING (TEFLON)
9 - CLUTCH PACK SNAP-RING (SELECTIVE)
21 - 246 AUTOMATIC TRANSMISSION - 42REBR/BE