Fig. 167 42RE Direct Clutch Pack Components
1 - REACTION PLATE 2 - PRESSURE PLATE
Fig. 168 Correct Position Of Direct Clutch Reaction
Plate
1 - REACTION PLATE COUNTERBORE
2 - DIRECT CLUTCH REACTION PLATE (FLUSH WITH END OF
HUB)
3 - CLUTCH HUB
Fig. 169 Correct Position Of Direct Clutch Pressure
Plate
1 - DIRECT CLUTCH PRESSURE PLATE
2 - CLUTCH PACK
3 - BE SURE SHOULDER SIDE OF PLATE FACES UPWARD
WJAUTOMATIC TRANSMISSION - 42RE 21 - 99
OVERDRIVE UNIT (Continued)
WARNING: THE NEXT STEP IN GEARTRAIN
ASSEMBLY INVOLVES COMPRESSING THE DIRECT
CLUTCH HUB AND SPRING. IT IS EXTREMELY
IMPORTANT THAT PROPER EQUIPMENT BE USED
TO COMPRESS THE SPRING AS SPRING FORCE IS
APPROXIMATELY 830 POUNDS. USE COMPRES-
SOR TOOL C-6227-1 AND A HYDRAULIC-TYPE
SHOP PRESS WITH A MINIMUM RAM TRAVEL OF 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.
(20) Position Compressor Tool 6227-1 on clutch
hub.
(21) Compress clutch hub and spring just enough
to place tension on hub and hold it in place.
(22) Slowly compress clutch hub and spring. Com-
press spring and hub only enough to expose ring
grooves for clutch pack snap ring and clutch hub
retaining ring.
(23) Realign clutch pack on hub and seat clutch
discs and plates in clutch drum.
(24) Install direct clutch pack snap-ring (Fig. 171).
Be very sure snap-ring is fully seated in clutch drum
ring groove.
(25) Install clutch hub retaining ring (Fig. 172). Be
very sure retaining ring is fully seated in sun gear
ring groove.
(26) Slowly release press ram, remove compressor
tools and remove geartrain assembly.
GEAR CASE
(1) Position park pawl and spring in case and
install park pawl shaft. Verify that end of spring
with 90É bend is hooked to pawl and straight end of
spring is seated against case.
(2) Install pawl shaft retaining bolt. Tighten bolt
to 27 N´m (20 ft. lbs.) torque.
(3) Install park lock reaction plug. Note that plug
has locating pin at rear (Fig. 173). Be sure pin is
seated in hole in case before installing snap-ring.
(4) Install reaction plug snap-ring (Fig. 174). Com-
press snap ring only enough for installation; do not
distort it.
Fig. 170 Direct Clutch
1 - CLUTCH HUB
2 - DIRECT CLUTCH PACK
3 - CLUTCH DRUM
Fig. 171 Direct Clutch Pack Snap-Ring Installation
1 - SPECIAL TOOL 6227-1
2 - DIRECT CLUTCH PACK SNAP-RING
Fig. 172 Clutch Hub Retaining Ring Installation
1 - SPECIAL TOOL 6227-1
2 - CLUTCH HUB RETAINING RING
21 - 100 AUTOMATIC TRANSMISSION - 42REWJ
OVERDRIVE UNIT (Continued)
(5) Install new seal in gear case. On 4x4 gear case,
use Tool Handle C-4171 and Installer C-3860-A to
seat seal in case. On4x2gear case, use same Han-
dle C-4171 and Installer C-3995-A to seat seal in
case.
(6) Verify that tab ends of rear bearing locating
ring extend into access hole in gear case (Fig. 175).
(7) Support geartrain on Tool 6227-1 (Fig. 176). Be
sure tool is securely seated in clutch hub.
(8) Install overdrive gear case on geartrain (Fig.
176).
(9) Expand front bearing locating ring with snap-
ring pliers (Fig. 177). Then slide case downward until
locating ring locks in bearing groove and release
snap-ring.
(10) Install locating ring access cover and gasket
in overdrive unit case (Fig. 178).
OVERDRIVE CLUTCH
(1) Install overdrive clutch reaction ring first.
Reaction ring is flat with notched ends (Fig. 179).
(2) Install wave spring on top of reaction ring (Fig.
180). Reaction ring and wave ring both fit in same
ring groove. Use screwdriver to seat each ring
securely in groove. Also ensure that the ends of the
two rings are offset from each other.
NOTE: The 42RE transmission has 3 overdrive
clutch discs and 2 plates.
(3) Assemble overdrive clutch pack (Fig. 181).
(4) Install overdrive clutch reaction plate first.
Fig. 173 Reaction Plug Locating Pin And Snap-Ring
1 - REACTION PLUG SNAP-RING (DO NOT OVERCOMPRESS
TO INSTALL)
2 - LOCATING PIN
3 - PARK LOCK REACTION PLUG
Fig. 174 Reaction Plug And Snap-Ring Installation
1 - REACTION PLUG SNAP-RING
2 - SNAP-RING PLIERS
Fig. 175 Correct Rear Bearing Locating Ring
Position
1 - CASE ACCESS HOLE
2 - TAB ENDS OF LOCATING RING
Fig. 176 Overdrive Gear Case Installation
1 - GEARTRAIN ASSEMBLY
2 - GEAR CASE
WJAUTOMATIC TRANSMISSION - 42RE 21 - 101
OVERDRIVE UNIT (Continued)
NOTE: The reaction plate is thinner than the pres-
sure plate in a 42RE transmission.
(5) Install first clutch disc followed by first clutch
plate. Then install remaining clutch discs and plates
in same order.
(6) Install clutch pack pressure plate.
(7) Install clutch pack wire-type retaining ring
(Fig. 182).
INTERMEDIATE SHAFT SPACER SELECTION
(1) Place overdrive unit in vertical position. Mount
it on blocks, or in workbench with appropriate size
mounting hole cut into it. Be sure unit is facing
upward for access to direct clutch hub. Also be sure
output shaft is not loaded and internal components
are moved rearward for accurate measurement.
(2) Determine correct thickness intermediate shaft
spacer as follows:
(a) Insert Special Tool 6312 through sun gear,
planetary 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. 183). 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
Gauge Alignment Tool 6312. Lock scale in place.
Remove dial caliper tool and note distance mea-
sured (Fig. 183).
(d) Select proper thickness end play spacer from
spacer chart based on distance measured (Fig.
184).
(e) Remove Gauge Alignment Tool 6312.
Fig. 177 Seating Locating Ring In Rear Bearing
1 - EXPAND BEARING LOCATING RING WITH SNAP-RING
PLIERS
2 - ACCESS HOLE
Fig. 178 Locating Ring Access Cover And Gasket
Installation
1 - TORX SCREWDRIVER (T25)
2 - ACCESS COVER SCREWS
Fig. 179 Overdrive Clutch Reaction Ring Installation
1 - REACTION RING
2 - CLUTCH HUB
Fig. 180 Overdrive Clutch Wave Spring Installation
1 - WAVE SPRING
21 - 102 AUTOMATIC TRANSMISSION - 42REWJ
OVERDRIVE UNIT (Continued)
OD THRUST PLATE SELECTION
(1) Place overdrive unit in vertical position. Mount
it on blocks, or in workbench with appropriate size
mounting hole cut into it. Be sure unit is facing
upward for access to direct clutch hub. Also be sure
output shaft is not loaded and internal components
are moved rearward for accurate measurement.
(2) 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. 185).
(b) Measure distance to clutch hub thrust bear-
ing seat at four points 90É apart. Then average
measurements by adding them and dividing by 4.
(c) Select and install required thrust plate from
information in thrust plate chart (Fig. 186).
Fig. 181 42RE Overdrive Clutch Components
1 - REACTION PLATE 2 - PRESSURE PLATE
Fig. 182 Overdrive Clutch Pack Retaining Ring
Installation
1 - OVERDRIVE CLUTCH PACK RETAINING RING
Fig. 183 Shaft End Play Measurement
1 - SPECIAL TOOL 6312
2 - SPECIAL TOOL 6311
3 - SPECIAL TOOL C-4962
WJAUTOMATIC TRANSMISSION - 42RE 21 - 103
OVERDRIVE UNIT (Continued)
REAR CLUTCH
DESCRIPTION
The rear clutch assembly (Fig. 224) 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.
Fig. 224 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 - 118 AUTOMATIC TRANSMISSION - 42REWJ
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 pis-
ton. The check-valve is needed to eliminate the pos-
sibility of plate drag caused by centrifugal force
acting on the residual fluid trapped in the clutch pis-
ton retainer.
DISASSEMBLY
(1) Remove fiber thrust washer from forward side
of clutch retainer.
(2) Remove input shaft front/rear seal rings.
(3) Remove selective clutch pack snap-ring (Fig.
225).(4) Remove top pressure plate, clutch discs, steel
plates, bottom pressure plate and wave snap-ring
and wave spring (Fig. 225).
(5) Remove clutch piston with rotating motion.
(6) Remove and discard piston seals.
(7) Remove input shaft snap-ring (Fig. 226). It
may be necessary to press the input shaft in slightly
to relieve tension on the snap-ring
(8) Press input shaft out of retainer with shop
press and suitable size press tool. Use a suitably
sized press tool to support the retainer as close to the
input shaft as possible.CLEANING
Clean the clutch components with solvent and dry
them with compressed air. Do not use rags or shop
towels to dry any of the clutch parts. Lint from such
materials will adhere to component surfaces and
could restrict or block fluid passages after assembly.
Fig. 225 Rear Clutch Components
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)
WJAUTOMATIC TRANSMISSION - 42RE 21 - 119
REAR CLUTCH (Continued)
INSPECTION
Replace the clutch discs if warped, worn, scored,
burned/charred, the lugs are damaged, or if the fac-
ing is flaking off. Replace the top and bottom pres-
sure plates if scored, warped, or cracked. Be sure the
driving lugs on the pressure and clutch plates are
also in good condition. The lugs must not be bent,
cracked or damaged in any way.
Replace the piston spring and wave spring if either
part is distorted, warped or broken.
Check the lug grooves in the clutch retainer. The
clutch and pressure plates should slide freely in the
slots. Replace the retainer if the grooves are worn or
damaged. Also check action of the check balls in the
retainer and piston. Each check ball must move
freely and not stick.
Replace the retainer bushing if worn, scored, or
doubt exists about bushing condition.
Inspect the piston and retainer seal surfaces for
nicks or scratches. Minor scratches can be removed
with crocus cloth. However, replace the piston and/or
retainer if the seal surfaces are seriously scored.
Check condition of the fiber thrust washer and
metal output shaft thrust washer. Replace either
washer if worn or damaged.
Check condition of the seal rings on the input shaft
and clutch retainer hub. Replace the seal rings only
if worn, distorted, or damaged. The input shaft front
seal ring is teflon with chamfered ends. The rear ring
is metal with interlocking ends.
Check the input shaft for wear, or damage. Replace
the shaft if worn, scored or damaged in any way.
ASSEMBLY
(1) Soak clutch discs in transmission fluid while
assembling other clutch parts.
(2) Install new seal rings on clutch retainer hub
and input shaft, if necessary, (Fig. 227) and (Fig.
228).
(a) Be sure clutch hub seal ring is fully seated in
groove and is not twisted.
(3) Lubricate splined end of input shaft and clutch
retainer with transmission fluid. Then press input
shaft into retainer (Fig. 229). Use a suitably sized
press tool to support retainer as close to input shaft
as possible.
(4) Install input shaft snap-ring (Fig. 226).
(5) Invert retainer and press input shaft in oppo-
site direction until snap-ring is seated.
(6) Install new seals on clutch piston. Be sure lip
of each seal faces interior of clutch retainer.
(7) Lubricate lip of piston seals with generous
quantity of MopartDoor Ease. Then lubricate
retainer hub and bore with light coat of transmission
fluid.
(8) Install clutch piston in retainer. Use twisting
motion to seat piston in bottom of retainer. A thin
strip of plastic (about 0.0209thick), can be used to
guide seals into place if necessary.
CAUTION: Never push the clutch piston straight in.
This will fold the seals over causing leakage and
clutch slip. In addition, never use any type of metal
tool to help ease the piston seals into place. Metal
tools will cut, shave, or score the seals.
(9) Install piston spring in retainer and on top of
piston (Fig. 230). Concave side of spring faces down-
ward (toward piston).
(10) Install wave spring in retainer (Fig. 230). Be
sure spring is completely seated in retainer groove.
(11) Install bottom pressure plate (Fig. 225).
Ridged side of plate faces downward (toward piston)
and flat side toward clutch pack.
(12) Install first clutch disc in retainer on top of
bottom pressure plate. Then install a clutch plate fol-
lowed by a clutch disc until entire clutch pack is
installed (4 discs and 3 plates are required) (Fig.
225).
(13) Install top pressure plate.
(14) Install selective snap-ring. Be sure snap-ring
is fully seated in retainer groove.
(15) Using a suitable gauge bar and dial indicator,
measure clutch pack clearance (Fig. 231).
(a) Position gauge bar across the clutch drum
with the dial indicator pointer on the pressure
plate (Fig. 231).
(b) Using two small screw drivers, lift the pres-
sure plate and release it.
Fig. 226 Removing Input Shaft Snap-Ring
1 - REAR CLUTCH RETAINER
2 - INPUT SHAFT SNAP-RING
3 - SNAP-RING PLIERS
21 - 120 AUTOMATIC TRANSMISSION - 42REWJ
REAR CLUTCH (Continued)