
•
OVERDRIVE
UNIT
OVERHAUL—42RH/46RH
21 - 333 Check the machined surfaces on the output shaft.
These surfaces should clean and smooth. Very minor nicks or scratches can be smoothed with crocus cloth.
Replace the shaft if worn, scored or damaged in any
way.
Check condition of the governor components. Re
place the governor drive seal rings if damaged. Be sure the drive ring grooves are in good condition. Check operation of the governor valve, weights and
shaft. The valves and weights should slide freely in
the governor body (Fig. 36).
There are two governor component changes in
current overdrive unit units. The first involves
the governor valve which is now made of alumi
num. The second involves the output shaft which has a spotface for governor valve end
clearance. The new aluminum valve is not inter
changeable. It must only be used with an output
shaft that has the spotface for valve end clear ance.
Inspect the governor support and the two oil pres
sure tubes (Fig. 36). The tubes are an integral
part of the support. Do not attempt to remove
them.
The oil tubes must not be pinched, kinked, col
lapsed, or distorted. Blow them out with compressed
air to be sure they are clear. The tubes are designed
to be a slip fit in the piston retainer boss. Do not modify the tube ends in an effort to make them fit
tighter.
Replace the governor support and the oil tubes as
an assembly if either component is damaged.
Check condition of the governor valve and weight
snap rings. Replace any snap ring that appears bent
or distorted. Replace any snap ring if its condition is
doubtful.
Inspect the output shaft bushings (Fig. 37). The
small bushing is the intermediate shaft pilot bush
ing. The large bushing is the overrunning clutch hub
bushing. Replace either bushing if scored, pitted, cracked, or worn.
The bushings can be removed with "blind hole
puller tools" such as Snap-On set CG40CB for small
bushings and set CG46 for large bushings. New
bushings can be installed with tools from an all pur
pose installer kit such as the Snap-On A257 bushing driver set.
OVERDRIVE
GEARTRAIN
ASSEMBLY
(1) Lubricate geartrain components with Mopar
ATF Plus or Dexron II™ transmission fluid. (2) Soak direct and overdrive clutch discs in trans
mission fluid before installation. (3) Install new pilot bushing and clutch hub bush
ing in output shaft if necessary (Fig. 37). Lubricate
new (or old) bushings with petroleum jelly. (4) Install front bearing and bearing snap ring on
output shaft (Fig. 38)
Fig.
37 Output Shaft
Bushing
Location
(5) Align and install annulus gear on output shaft
(Fig. 38). (6) Install annulus snap ring (Fig. 38).
Fig.
38 Installing
Annulus
Gear And
Snap Ring
(7) Align and install clutch drum on annulus gear
(Fig. 39). Be sure drum is engaged in annulus gear
lugs.
(8) Install clutch drum outer retaining ring (Fig.
31).
(9) Slide clutch drum forward and install inner re
taining ring (Fig. 39).
(10) Install overrunning clutch on hub (Fig. 40).
Note that clutch only fits one way. Shoulder on
clutch should seat in small recess at edge of
hub.
(11) Install thrust bearing on overrunning clutch
hub (Fig. 41). Use generous amount of petroleum
jelly to hold bearing in place for installation. Bear ing fits one way only. Be sure bearing is seated squarely against hub. Reinstall bearing if it does
not seat squarely.

21
- 334
OVERDRIVE
UNIT
OVERHAUL—42RH/46RH
•
INNER
RETAINING RING ANNULUS
GEAR
J9121-294
Fig.
39 installing
Clutch
Drum
Inner
Retaining
Ring
CLUTCH HUB OVERRUNNING
CLUTCH
J9121-322
Fig.
40
Assembling
Overrunning
Clutch
And Hub
BE
SURE
THRUST
BEARING
IS
SEATED SQUARELY
AGAINST CLUTCH
HUB
CLUTCH HUB
J9121-323
Fig.
41 Installing Overrunning
Clutch
Thrust
Bearing
(12) Install overrunning clutch (Fig. 42). Insert
snap
ring
pliers in hub splines. Expand pliers to grip
hub.
Then install assembly with counterclockwise, twisting motion.
CLUTCH
DRUM OVERRUNNING
CLUTCH
ASSEMBLY
EXPAN DING-TYPE
SNAP
RING
PLIERS
OVERRUNNING
CLUTCH ASSEMBLY
SEATED
IN
OUTPUT
SHAFT
CLUTCH DRUM
ANNULUS
GEAR
J9121-314
Fig.
42 Installing Overrunning
Clutch
(13) Install planetary gear in annulus gear (Fig.
43).
Be sure planetary pinions are fully seated in annulus gear before proceeding.
PLANETARY
GEAR
ANNULUS
GEAR
J9121-324
Fig.
43 Installing Planetary Gear

•
OVERDRIVE
UNIT
OVERHAUL—42RH/46RH
21 - 335 (14) Install direct clutch spring plate on sun gear.
Shoulder side of plate should face outward and to
ward front. Then secure plate to sun gear with snap
ring (Fig. 44).
SUN
Fig.
44 Sun Gear And
Spring
Plate
Assembly
(15) Coat planetary thrust bearing and bearing
contact surface of spring plate with generous amount
of petroleum jelly. This will help hold bearing in
place during installation.
(16) Install planetary thrust bearing on sun gear
(Fig. 45). Slide bearing onto gear and seat it against
spring plate as shown. Bearing fits one way only.
If it does not seat squarely against spring plate,
remove and reposition bearing.
J9121-326
Fig.
45 Installing Planetary Thrust Bearing
(17) Install assembled sun gear, spring plate and
thrust bearing (Fig. 46). Be sure sun gear and thrust
bearing are fully seated before proceeding.
(18) Align splines in hubs of planetary gear and
overrunning clutch with Alignment tool 6227-2 (Fig.
47).
Insert tool through sun gear and into splines of
both hubs. Be sure alignment tool is fully seated be fore proceeding.
Fig.
46 Sun Gear
Installation
(19) Install direct clutch spring. Be sure spring is
properly seated on spring plate (Fig. 47).
Fig.
47 Installing Direct
Clutch
Spring
(20) Assemble direct clutch pack for installation on
hub (Fig. 48).
(21) Install direct clutch reaction plate on clutch
hub.
Note that one side of reaction plate is coun- terbored. Be sure this side faces rearward. Splines at rear of hub are raised slightly. Coun-
terbore in plate fits over raised splines. Plate should be flush with this end of hub (Fig. 49).
(22) Install remainder of direct clutch components
as follows: (a) Install first clutch disc on reaction plate fol
lowed by a steel plate.
(b) Install remaining discs and plates alternately
until required number of discs and plates are in stalled.

21 - 336
OVERDRIVE
UNIT
OVERHAUL—42RH/46RH
CLUTCH
DISCS
(6) A
42RH
PRESSURE
PLATE
REACTION
PLATE
CLUTCH
PLATES
(5)
CLUTCH
DISCS
(8)
46RH
PRESSURE
PLATE
REACTION
PLATE
COUNTERBORE
REACTION
CLUTCH
PLATE
PLATES
(7)
Fig. 48 Direct Clutch Pack Components (c) Check direct clutch pack. 42RH requires 6
discs and 5 steel plates. 46RH requires 8 discs and 7 steel plates (Fig. 48).
(d) Last clutch pack item installed is clutch pres
sure plate. Be sure plate is installed with shoulder
side of plate facing upward (Fig. 50). (23) Install clutch hub and clutch pack on direct
clutch spring (Fig. 51).
(24) Mount geartrain assembly in shop press (Fig.
52)
WARNING:
THE
NEXT
STEP
IN
GEARTRAIN
AS
SEMBLY
INVOLVES COMPRESSING
THE
DIRECT CLUTCH
HUB AND
SPRING.
IT IS
EXTREMELY
IM
PORTANT
THAT
PROPER EQUIPMENT
BE
USED
TO COMPRESS
THE
SPRING AS SPRING FORCE
IS
APPROXIMATELY 800 POUNDS. USE SPRING COM
PRESSOR
TOOL
C-6227-1
AND A
HYDRAULIC-
TYPE 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.
J922M41
(25) Position Compressor Tool 6227-2 on clutch
hub (Fig. 52). (26) Position Tool MB990891 or similar size tool on
top of compressor tool (Fig. 52). Similar size tool
DIRECT
CLUTCH
REACTION
PLATE
(FLUSH
WITH
END OF
HUB)
CLUTCH
HUB
J9121-329
Fig.
49
Correct
Position
Of
Direct
Clutch
Reaction
Plate

OVERDRIVE
UNIT
OVERHAUL—42RH/4IRH
21 - 337
DIRECT
CLUTCH
PRESSURE PLATE
BE
SURE
SHOULDER
SIDE
OF
PLATE
FACES
UPWARD
CLUTCH
PACK
J9121-330
Fig.
50 Correct Position Of Direct
Clutch
Pressure
Plate
DIRECT
CLUTCH PACK
CLUTCH
HUB
J9121-331
should have minimum outside diameter of 3-1/2 inch,
minimum wall thickness of 1/4 inch and be approxi
mately 4 inches long.
(27) Slide direct clutch pack upwards on hub (Fig.
52).
Slide pack upward and set it partially on edge of
hub and compressor tool as shown in Figure 52.
SPECIAL
TOOL
MB990891
SPECIAL TOOL 6227-2
CLUTCH
HUB
SPECIAL
TOOL 6227-1
DIRECT
CLUTCH PACK
CLUTCH
DRUM
J9221-2
Fig.
52
Mounting
Geartrain
Assembly
In
Shop
Press
(28) Slowly compress clutch hub and spring (Fig.
53).
Compress spring and hub only enough to expose
ring grooves for clutch pack snap ring and clutch hub
retaining ring.
(29) Realign clutch pack on hub and seat clutch
discs and plates in clutch drum (Fig. 53).
SPECIAL
TOOL 6227-2 DIRECT
CLUTCH
PLATES/DISCS
Fig.
51 Installing
Assembled
Direct
Clutch
Pack
And
CLUTCH
Hub
DRUM J9221-3
Fig.
53 Seating
Clutch
Pack
In
Drum

21
- 338
OVERDRIVE
UNIT
OVERHAUL—42RH/46RH
• (30) Install direct clutch pack snap ring
(Fig. 54).
Be very sure snap ring
Is
fully seated
In
clutch drum ring groove.
(31) Install clutch
hub
retaining ring
(Fig. 55). Be
very sure retaining ring
Is
fully seated
in sun
gear ring groove.
(32) Slowly release press
ram,
remove compressor
tools
and
remove geartrain assembly.
Fig.
54
Installing Direct
Clutch
Pack Snap Ring
J9221-5
Fig.
55
Installing
Clutch
Hub
Retaining
Ring
OVERDRIVE
UNIT ASSEMBLY AND ADJUSTMENT
(1) Install front bearing
and
snap ring
on
output
shaft
(Fig. 56). Be
sure locating ring groove
in
bearing
is
toward rear
of
shaft. (2) Install governor drive
key in
output shaft
(Fig.
56).
(3) Install
new
seal rings
on
governor drive.
Be
sure ring ends
are
securely interlocked before pro
ceeding
(Fig. 57).
(4) Assemble governor drive
and
body.
Be
sure fil
ter
is
properly seated
and
positioned
in
governor
body before tightening attaching bolts. (5) Assemble governor inner
and
outer weights
and spring. Then install weight assembly
in
governor
Fig.
56
Front Bearing
And
Drive
Key
Installation
GOVERNOR
BODY
GOVERNOR DRIVE
Fig.
57
Governor
Drive
Seal Rings
Fig.
58
Installing
Governor
Weight
Assembly
body
(Fig. 58). Be
sure
all
retaining snap rings
are
securely seated.

21
- 340
OVERDRIVE
UNIT OVERHAUL—42RH/46RH
(16) Install governor support snap ring (Fig. 64).
SNAP
/ ©
^S^^S^
/^SCREWDRIVER RING
7
8921-264
Fig.
64 Installing
Governor
Support
Snap Ring
(17) Install output shaft front bearing locating ring
in case (Fig. 65).
OUTPUT SHAFT
FRONT BEARING LOCATING RING
J9121-339
Fig.
65 Front Bearing Locating
Ring
Installation
(18) Support geartrain on Tool 6227-1 (Fig. 66). Be
sure tool is securely seated in clutch hub. (19) Install overdrive unit case over geartrain (Fig.
66).
(20) Expand front bearing locating ring with snap
ring pliers. Then slide case downward until locating ring locks in bearing groove and release snap ring.
(21) Install locating ring access plate and gasket in
overdrive unit case (Fig. 9).
(22) Install overdrive clutch components as follows: (a) Install reaction ring first. Reaction ring is
flat with notched ends (Fig. 67). (b) Install wave spring on top of reaction ring.
Reaction ring and wave ring both fit in same
ring groove. Use screwdriver to seat each ring se curely in groove. (c) Install reaction plate (Fig. 68). (d) Install first clutch disc followed by first
clutch plate.
SPECIAL
TOOL
6227-2
CASE
GEARTRAIN
SPECIAL
TOOL
6227-1
J9221-6
Fig.
66 Installing Overdrive
Case
On
Geartrain
(e) Install remaining clutch discs and plates in
same order.
(f) Verify clutch pack before proceeding:
• gas engine version of 42RH/46RH, requires 4
clutch discs, 3 steel plates, 1 reaction plate and 1
pressure plate.
• diesel engine version of 46RH, requires 5 clutch
discs,
4 steel plates, 1 reaction plate and 1 pressure
plate.
(g) Install clutch pack pressure plate (Fig. 68).
(h) Install clutch pack wire-type retaining ring
(Fig. 67).
WAVE
SPRING
REACTION RING RETAINING RING
(WIRE-TYPE)
J9121-470
Fig.
67 Overdrive
Clutch
Ring
Identification
(23) Place overdrive unit in vertical position.
Mount unit in vise or in workbench with appropriate size mounting hole cut into it. Be sure unit is facing
upward for access to direct clutch hub.

•
NP205
TRANSFER
CASE
21 - 341
REACTION
PLATE
CLUTCH
DISCS
(4)
J9321-227
Fig.
68 Overdrive
Clutch
Pack
(Gas
Engine
Version
Shown)
(24) Determine correct thickness intermediate
shaft spacer as follows: (a) Insert Special Tool 6312 through sun gear, plan
etary gear and into pilot bushing in output shaft. Be
sure tool bottoms against planetary shoulder.
(b) Position Gauge Tool 6311 across face of over
drive case (Fig. 69). Then position Dial Caliper C-4962 over gauge tool.
(c) Extend sliding scale of dial caliper downward
through gauge tool slot until scale contacts end of
Alignment Tool 6312. Lock scale in place. Remove
dial caliper tool and note distance measured (Fig. 69). (d) Select proper thickness end play spacer from
spacer chart based on distance measured (Fig. 70). (e) Remove Alignment Tool 6312.
SPECIAL
TOOL
6311
SPECIAL
TOOL
6312
J9221-47
Fig.
69 Shaft End Play Measurement
(25) Determine correct thickness overdrive piston
thrust plate as follows: (a) Position Gauge Tool 6311 across face of over
drive case. Then position Dial Caliper C-4962 over
gauge tool (Fig. 71).
(b) Measure distance to clutch hub thrust bear
ing seat at four points 90° apart. Then average
measurements by adding them and dividing by 4.
End
Play
Measurement
(Inches)
Spacer
Thickness
(Inches)
.7336
-
.7505
.158
- .159
.7506
-
.7675
.175
- .176
.7676
-
.7855
.193
- .194
.7856-
.8011
.211
- .212
J9121-341 Fig. 70
Intermediate
Shaft
End
Play
Spacer
Selection
(c) Select and install required thrust plate from in
formation provided in thrust plate chart (Fig. 72).
(26) Leave Alignment Tool 6227-2 in place. Tool
will keep planetary and clutch hub splines in align
ment until overdrive unit is ready for installation on
transmission.
(27) Set overdrive unit aside for final assembly of
transmission.
Fig.
71 Overdrive
Piston
Thrust
Plate
Measurement
End
Ploy
Measurement
(Inches)
Spacer
Thickness
(Inches)
1.7500
- 1.7649
.108
- .110
1.7650-
1.7799
.123
- .125
1.7800
- 1.7949
.138
- .140
1.7950
- 1.8099
.153
- .155
1.8100
- 1.8249
.168
- .170
1.8250
- 1.8399
.183
- .185
1.8400
- 1.8549
.198
- .200
1.8550
- 1.8699
.213
- .215
1.8700
- 1.8849
.228
- .230
1.8850
- 1.8999
.243
- .245
J9121-342
Fig.
72 Overdrive
Piston
Thrust
Plate
Selection