Page 2057 of 2895

OVERDRIVE CLUTCH
DESCRIPTION
The overdrive clutch (Fig. 132) 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 pro-
vided 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 overdrive clutch discs are attached to the over-
drive clutch hub while the overdrive clutch plates, reac-
tion plate, and pressure plate are lugged to the
overdrive housing. This allows the intermediate shaft totransfer the engine torque to the planetary gear and
overrunning 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 appli-
cation of the clutch pack.
OVERDRIVE SWITCH
DESCRIPTION
The overdrive OFF (control) switch is located in
the shift lever arm (Fig. 133). The switch is a
momentary contact device that signals the PCM to
toggle current status of the overdrive function.
OPERATION
At key-on, overdrive operation is allowed. Pressing
the switch once causes the overdrive OFF mode to be
entered and the overdrive OFF switch lamp to be
illuminated. Pressing the switch a second time
causes normal overdrive operation to be restored and
the overdrive lamp to be turned off. The overdrive
OFF mode defaults to ON after the ignition switch is
cycled OFF and ON. The normal position for the con-
trol switch is the ON position. The switch must be in
this position to energize the solenoid and allow a 3-4
upshift. The control switch indicator light illuminates
only when the overdrive switch is turned to the OFF
position, or when illuminated by the transmission
control module.
Fig. 132 Overdrive Clutch
1 - REACTION PLATE 2 - PRESSURE PLATE
21 - 218 AUTOMATIC TRANSMISSION - 46REDR
Page 2058 of 2895

DIAGNOSIS AND TESTING - OVERDRIVE
ELECTRICAL CONTROLS
The overdrive off switch, valve body solenoid, case
connectors and related wiring can all be tested with
a 12 volt test lamp or a volt/ohmmeter. Check conti-
nuity of each component when diagnosis indicates
this is necessary.
Switch and solenoid continuity should be checked
whenever the transmission fails to shift into fourth
gear range.
REMOVAL
(1) Using a plastic trim tool, remove the overdrive
off switch retainer from the shift lever (Fig. 134).
(2) Pull the switch outwards to release it from the
connector in the lever (Fig. 135)
INSTALLATION
NOTE: There is enough slack in the wire to pull out
the connector from the lever.
(1) Pull the connector out of the lever just enough
to grasp it.
CAUTION: Be careful not to bend the pins on the
overdrive off switch. Use care when installing the
switch, as it is not indexed, and can be accidentally
installed incorrectly.
(2) Install the overdrive off switch into the connec-
tor (Fig. 136)
(3) Push the overdrive off switch and wiring into
the shift lever.
(4) Install the overdrive off switch retainer onto
the shift lever.
Fig. 133 Overdrive Off Switch
Fig. 134 Overdrive Off Switch Retainer
1 - GEAR SHIFT LEVER
2 - OVERDRIVE OFF SWITCH RETAINER
3 - PLASTIC TRIM TOOL
Fig. 135 Remove the Overdrive Off Switch
1 - GEAR SHIFT LEVER
2 - OVERDRIVE OFF SWITCH
Fig. 136 Install the Overdrive Off Switch
1 - GEAR SHIFT LEVER
2 - OVERDRIVE OFF SWITCH WIRING CONNECTOR
3 - OVERDRIVE OFF SWITCH
DRAUTOMATIC TRANSMISSION - 46RE 21 - 219
OVERDRIVE SWITCH (Continued)
Page 2059 of 2895

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 neces-
sary.
(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. 137).
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.
DISASSEMBLY
(1) Remove transmission speed sensor and o-ring
seal from overdrive case (Fig. 138).
(2) Remove overdrive piston thrust bearing (Fig.
139).
Fig. 137 Overdrive Unit Bolts
1 - OVERDRIVE UNIT
2 - ATTACHING BOLTS (7)
Fig. 138 Transmission Speed Sensor
1 - SOCKET AND WRENCH
2 - SPEED SENSOR
3 - O-RING
21 - 220 AUTOMATIC TRANSMISSION - 46REDR
Page 2060 of 2895
OVERDRIVE PISTON
(1) Remove overdrive piston thrust plate (Fig.
140). Retain thrust plate. It is a select fit part and
may possibly be reused.(2) Remove intermediate shaft spacer (Fig. 141).
Retain spacer. It is a select fit part and may possibly
be reused.
(3) Remove overdrive piston from retainer (Fig.
142).
Fig. 139 Overdrive Piston Thrust Bearing Removal/
Installation
1 - THRUST BEARING
2 - OVERDRIVE PISTON
3 - THRUST PLATE
Fig. 140 Overdrive Piston Thrust Plate Removal/
Installation
1 - OVERDRIVE PISTON
2 - OVERDRIVE PISTON SPACER (SELECT FIT)
Fig. 141 Intermediate Shaft Spacer Location
1 - INTERMEDIATE SHAFT
2 - INTERMEDIATE SHAFT SPACER (SELECT FIT)
Fig. 142 Overdrive Piston Removal
1 - PISTON RETAINER
2 - OVERDRIVE PISTON
DRAUTOMATIC TRANSMISSION - 46RE 21 - 221
OVERDRIVE UNIT (Continued)
Page 2061 of 2895
OVERDRIVE CLUTCH PACK
(1) Remove overdrive clutch pack wire retaining
ring (Fig. 143).
(2) Remove overdrive clutch pack (Fig. 144).
(3) Note position of clutch pack components for
assembly reference (Fig. 145).
OVERDRIVE GEARTRAIN
(1) Remove overdrive clutch wave spring (Fig.
146).
(2) Remove overdrive clutch reaction snap-ring
(Fig. 147). Note that snap-ring is located in same
groove as wave spring.
Fig. 143 Removing Overdrive Clutch Pack Retaining
Ring
1 - OVERDRIVE CLUTCH PACK RETAINING RING
Fig. 144 Overdrive Clutch Pack Removal
1 - OVERDRIVE CLUTCH PACK
Fig. 145 Overdrive Clutch Component Position -
Typical
1 - REACTION PLATE 3 - PRESSURE PLATE
2 - CLUTCH PLATES (3) 4 - CLUTCH DISCS (4)
Fig. 146 Overdrive Clutch Wave Spring Removal
1 - WAVE SPRING
Fig. 147 Overdrive Clutch Reaction Snap-Ring
Removal
1 - REACTION RING
2 - CLUTCH HUB
21 - 222 AUTOMATIC TRANSMISSION - 46REDR
OVERDRIVE UNIT (Continued)
Page 2062 of 2895
(3) Remove TorxŸ head screws that attach access
cover and gasket to overdrive case (Fig. 148).
(4) Remove access cover and gasket (Fig. 149).
(5) Expand output shaft bearing snap-ring with
expanding-type snap-ring pliers. Then push output
shaft forward to release shaft bearing from locating
ring (Fig. 150).(6) Lift gear case up and off geartrain assembly
(Fig. 151).
(7) Remove snap-ring that retains rear bearing on
output shaft.
(8) Remove rear bearing from output shaft (Fig.
152).
Fig. 148 Access Cover Screw Removal
1 - TORX SCREWDRIVER (T25)
2 - ACCESS COVER SCREWS
Fig. 149 Access Cover And Gasket Removal
1 - ACCESS COVER AND GASKET
Fig. 150 Releasing Bearing From Locating Ring
1 - EXPAND BEARING LOCATING RING WITH SNAP-RING
PLIERS
2 - ACCESS HOLE
Fig. 151 Removing Geartrain
1 - GEARTRAIN ASSEMBLY
2 - GEAR CASE
Fig. 152 Rear Bearing Removal
1 - OUTPUT SHAFT
2 - REAR BEARING
3 - SNAP-RING
DRAUTOMATIC TRANSMISSION - 46RE 21 - 223
OVERDRIVE UNIT (Continued)
Page 2063 of 2895

DIRECT CLUTCH, HUB AND SPRING
WARNING: THE NEXT STEP IN DISASSEMBLY
INVOLVES COMPRESSING THE DIRECT CLUTCH
SPRING. IT IS EXTREMELY IMPORTANT THAT PROPER
EQUIPMENT BE USED TO COMPRESS THE SPRING AS
SPRING FORCE IS APPROXIMATELY 830 POUNDS. USE
SPRING COMPRESSOR TOOL 6227-1 AND A HYDRAU-
LIC SHOP PRESS WITH A MINIMUM RAM TRAVEL OF
5-6 INCHES. THE PRESS MUST ALSO HAVE A BED
THAT CAN BE ADJUSTED UP OR DOWN AS REQUIRED.
RELEASE CLUTCH SPRING TENSION SLOWLY AND
COMPLETELY TO AVOID PERSONAL INJURY.
(1)Mount geartrain assembly in shop press (Fig. 153).
(2) Position Compressor Tool 6227-1 on clutch hub
(Fig. 153). Support output shaft flange with steel
press plates as shown and center assembly under
press ram.
(3) Apply press pressure slowly. Compress hub and
spring far enough to expose clutch hub retaining ring
and relieve spring pressure on clutch pack snap-ring
(Fig. 153).(4) Remove direct clutch pack snap-ring (Fig. 154).
(5)
Remove direct clutch hub retaining ring (Fig. 155).
Fig. 153 Geartrain Mounted In Shop Press
1 - PRESS RAM
2 - SPECIAL TOOL C-3995-A (OR SIMILAR TOOL)
3 - CLUTCH HUB
4 - PLATES
5 - PRESS BED
6 - SPECIAL TOOL 6227-1
Fig. 154 Direct Clutch Pack Snap-Ring Removal
1 - CLUTCH HUB
2 - SPECIAL TOOL 6227-1
3 - DIRECT CLUTCH PACK SNAP-RING
4 - PRESS PLATES
5 - CLUTCH DRUM
Fig. 155 Direct Clutch Hub Retaining Ring Removal
1 - SPECIAL TOOL 6227-1
2 - CLUTCH HUB RETAINING RING
3 - PRESS BED
4 - PRESS PLATES
21 - 224 AUTOMATIC TRANSMISSION - 46REDR
OVERDRIVE UNIT (Continued)
Page 2064 of 2895

(6) Release press load slowly and completely (Fig.
156).
(7) Remove Special Tool 6227-1. Then remove
clutch pack from hub (Fig. 156).
GEARTRAIN
(1) Remove direct clutch hub and spring (Fig. 157).
(2) Remove sun gear and spring plate. Then
remove planetary thrust bearing and planetary gear
(Fig. 158).(3) Remove overrunning clutch assembly with
expanding type snap-ring pliers (Fig. 159). Insert pli-
ers into clutch hub. Expand pliers to grip hub splines
and remove clutch with counterclockwise, twisting
motion.
Fig. 159 Overrunning Clutch Assembly Removal/
Installation
1 - OVERRUNNING CLUTCH
2 - NEEDLE BEARING
Fig. 156 Direct Clutch Pack Removal
1 - SPECIAL TOOL 6227-1
2 - DIRECT CLUTCH HUB
3 - DIRECT CLUTCH PACK
Fig. 157 Direct Clutch Hub And Spring Removal
1 - DIRECT CLUTCH SPRING
2 - DIRECT CLUTCH HUB
Fig. 158 Removing Sun Gear, Thrust Bearing And
Planetary Gear
1 - PLANETARY GEAR
2 - PLANETARY THRUST BEARING
3 - CLUTCH SPRING PLATE
4 - SPRING PLATE SNAP-RING
5 - SUN GEAR
DRAUTOMATIC TRANSMISSION - 46RE 21 - 225
OVERDRIVE UNIT (Continued)