BOOST VALVE
The boost valve (Fig. 277) provides increased fluid
apply pressure to the overdrive clutch during 3-4
upshifts (Fig. 278), and when accelerating in fourth
gear. The boost valve also serves to increase line
pressure during torque converter lock-up.
REMOVAL
The valve body can be removed for service without
having to remove the transmission assembly.
The valve body can be disassembled for cleaning
and inspection of the individual components.
The only replaceable valve body components are:
²Manual lever.
²Manual lever washer, seal, E-clip, and shaft
seal.
²Manual lever detent ball.
²Throttle lever.
²Fluid filter.
²Pressure adjusting screw bracket.
²Governor pressure solenoid.
²Governor pressure sensor (includes transmission
temperature thermistor).
²Converter clutch/overdrive solenoid assembly
and harness.
²Governor housing gasket.
²Solenoid case connector O-rings.
(1) Shift transmission into NEUTRAL.
(2) Raise vehicle.
(3) Remove gearshift and throttle levers from shaft
of valve body manual lever.
(4) Disconnect wires at solenoid case connector
(Fig. 279).
(5) Position drain pan under transmission oil pan.
(6) Remove transmission oil pan and gasket.
(7) Remove fluid filter from valve body.
(8) Remove bolts attaching valve body to transmis-
sion case.
(9) Lower valve body enough to remove accumula-
tor piston and springs.
(10) Work manual lever shaft and electrical con-
nector out of transmission case.
(11) Lower valve body, rotate valve body away
from case, pull park rod out of sprag, and remove
valve body (Fig. 280).
Fig. 277 Boost Valve Before Lock-up
Fig. 278 Boost Valve After Lock-up
Fig. 279 Transmission Case Connector
1 - SOLENOID CASE CONNECTOR
2 - PARK/NEUTRAL POSITION SWITCH
21 - 154 AUTOMATIC TRANSMISSION - 42REWJ
VALVE BODY (Continued)
²pressure adjusting screw and bracket assembly
²throttle lever
²manual lever and shaft seal
²throttle lever shaft seal, washer, and E-clip
²fluid filter and screws
²detent ball and spring
²valve body screws
²governor pressure solenoid
²governor pressure sensor and retaining clip
²park lock rod and E-clip
ASSEMBLY
CAUTION: Do not force valves or plugs into place
during reassembly. If the valve body bores, valves
and plugs are free of distortion or burrs, the valve
body components should all slide into place easily.
In addition, do not overtighten the transfer plate
and valve body screws during reassembly. Over-
tightening can distort the housings resulting in
valve sticking, cross leakage and unsatisfactory
operation. Tighten valve body screws to recom-
mended torque only.
LOWER HOUSING
(1) Lubricate valves, springs, and the housing
valve and plug bores with clean transmission fluid
(Fig. 309).
(2) Install 3-4 timing valve spring and valve in
lower housing.
(3) Install 3-4 quick fill valve in lower housing.
(4) Install 3-4 quick fill valve spring and plug in
housing.
(5) Install timing valve end plate. Tighten end
plate screws to 4 N´m (35 in. lbs.) torque.
3-4 ACCUMULATOR
(1) Lubricate accumulator piston, seals and hous-
ing piston bore with clean transmission fluid (Fig.
310).
(2) Install new seal rings on accumulator piston.
(3) Install piston and spring in housing.
(4) Install end plate on housing.
TRANSFER PLATE
(1) Install rear clutch and rear servo check balls in
transfer plate (Fig. 311).
(2) Install filter screen in upper housing separator
plate (Fig. 312).
(3) Align and position upper housing separator
plate on transfer plate (Fig. 313).
(4) Install brace plate (Fig. 313). Tighten brace
attaching screws to 4 N´m (35 in. lbs.) torque.
(5) Install remaining separator plate attaching
screws. Tighten screws to 4 N´m (35 in. lbs.) torque.
UPPER AND LOWER HOUSING
(1) Position upper housing so internal passages
and check ball seats are facing upward. Then install
check balls in housing (Fig. 314). Eight check balls
are used. The single large check ball is approxi-
mately 8.7 mm (11/32 in.) diameter. The single small
check ball is approximately 4.8 mm (3/16 in.) in
diameter. The remaining 6 check balls are approxi-
mately 6.3 mm (1/4 in.) in diameter.
(2) Position assembled transfer plate and upper
housing separator plate on upper housing (Fig. 315).
Be sure filter screen is seated in proper housing
recess.
Fig. 311 Rear Clutch And Rear Servo Check Ball
Locations
1 - REAR CLUTCH CHECK BALL
2 - REAR SERVO CHECK BALL
3 - TRANSFER PLATE
Fig. 312 Separator Plate Filter Screen Installation
1 - UPPER HOUSING SEPARATOR PLATE
2 - FILTER SCREEN
WJAUTOMATIC TRANSMISSION - 42RE 21 - 167
VALVE BODY (Continued)
(3) Install the ECE check ball into the transfer
plate (Fig. 301). The ECE check ball is approximately
4.8 mm (3/16 in.) in diameter.
(4) Position lower housing separator plate on
transfer plate (Fig. 316).
(5) Install lower housing on assembled transfer
plate and upper housing (Fig. 317).
(6) Install and start all valve body screws by hand
except for the screws to hold the boost valve tube
brace. Save those screws for later installation. Then
tighten screws evenly to 4 N´m (35 in. lbs.) torque.
Start at center and work out to sides when tighten-
ing screws (Fig. 317).
Fig. 313 Brace Plate
1 - BRACE
2 - TRANSFER PLATE
3 - SEPARATOR PLATE
Fig. 314 Check Ball Locations In Upper Housing
1 - SMALL DIAMETER CHECK BALLS (6)
2 - LARGE DIAMETER CHECK BALL (1)
Fig. 315 Installing Transfer Plate On Upper Housing
1 - FILTER SCREEN
2 - TRANSFER PLATE/SEPARATOR PLATE ASSEMBLY
3 - UPPER HOUSING
Fig. 316 Lower Housing Separator Plate
1 - BE SURE TO ALIGN BORES
2 - TRANSFER PLATE
3 - LOWER HOUSING (OVERDRIVE) SEPARATOR PLATE
21 - 168 AUTOMATIC TRANSMISSION - 42REWJ
VALVE BODY (Continued)
UPPER HOUSING VALVE AND PLUG
Refer to (Fig. 318), (Fig. 319) and (Fig. 320) to per-
form the following steps.
(1) Lubricate valves, plugs, springs with clean
transmission fluid.
(2) Assemble regulator valve line pressure plug,
sleeve, throttle plug and spring. Insert assembly in
upper housing and install cover plate. Tighten cover
plate screws to 4 N´m (35 in. lbs.) torque.
(3) Install 1-2 and 2-3 shift valves and springs.
(4) Install 1-2 shift control valve and spring.
(5) Install retainer, spring, limit valve, and 2-3
throttle plug from limit valve housing.
Fig. 318 Shuttle And Boost Valve Components
1 - SPRING 8 - SHUTTLE VALVE COVER
2 - RETAINER 9 - SHUTTLE VALVE
3 - BOOST VALVE 10 - SHUTTLE VALVE PRIMARY SPRING
4 - BOOST VALVE PLUG 11 - GOVERNOR PLUG COVER
5 - SPRING GUIDES 12 - THROTTLE PLUG
6 - E-CLIP 13 - UPPER HOUSING
7 - SHUTTLE VALVE SECONDARY SPRING 14 - BOOST VALVE COVER
Fig. 317 Installing Lower Housing On Transfer Plate
And Upper Housing
1 - VALVE BODY SCREWS (13)
2 - LOWER HOUSING
3 - UPPER HOUSING
4 - TRANSFER PLATE
WJAUTOMATIC TRANSMISSION - 42RE 21 - 169
VALVE BODY (Continued)
(6) Install limit valve housing and cover plate.
Tighten screws to 4 N´m (35 in. lbs.).
(7) Install shuttle valve as follows:
(a) Insert plastic guides in shuttle valve second-
ary spring and install spring on end of valve.
(b) Install shuttle valve into housing.
(c) Hold shuttle valve in place.
(d) Compress secondary spring and install E-clip
in groove at end of shuttle valve.
(e) Verify that spring and E-clip are properly
seated before proceeding.(8) Install shuttle valve cover plate. Tighten cover
plate screws to 4 N´m (35 in. lbs.) torque.
(9) Install 1-2 and 2-3 valve governor plugs in
valve body.
(10) Install shuttle valve primary spring and
throttle plug.
(11) Align and install governor plug cover. Tighten
cover screws to 4 N´m (35 in. lbs.) torque.
Fig. 319 Upper Housing Control Valve Locations
1 - UPPER HOUSING 8 - MANUAL VALVE
2 - REGULATOR VALVE 9 - 1-2 GOVERNOR PLUG
3 - SWITCH VALVE 10 - GOVERNOR PLUG COVER
4 - REGULATOR VALVE SPRING 11 - THROTTLE PLUG
5 - KICKDOWN VALVE 12 - 2-3 GOVERNOR PLUG
6 - KICKDOWN DETENT 13 - SHUTTLE VALVE PRIMARY SPRING
7 - THROTTLE VALVE AND SPRING
21 - 170 AUTOMATIC TRANSMISSION - 42REWJ
VALVE BODY (Continued)
BOOST VALVE TUBE AND BRACE
(1) Position valve body assembly so lower housing
is facing upward (Fig. 321).
(2) Lubricate tube ends and housing ports with
transmission fluid or petroleum jelly.
(3) Start tube in lower housing port first. Then
swing tube downward and work opposite end of tube
into upper housing port (Fig. 321).
(4) Insert and seat each end of tube in housings.
(5) Slide tube brace under tube and into alignment
with valve body screw holes (Fig. 322).
(6) Install and finger tighten three screws that
secure tube brace to valve body housings (Fig. 322).
(7) Bend tube brace tabs up and against tube to
hold it in position (Fig. 323).
(8) Tighten all valve body housing screws to 4 N´m
(35 in. lbs.) torque after tube and brace are installed.
Tighten screws in diagonal pattern starting at center
and working outward.
Fig. 321 Boost Valve Tube
1 - BOOST VALVE TUBE
2 - LOWER HOUSING
3 - DISENGAGE THIS END OF TUBE FIRST
4 - UPPER HOUSING
Fig. 322 Boost Valve Tube And Brace
1 - BOOST VALVE TUBE
2 - TUBE BRACE
Fig. 323 Securing Boost Valve Tube With Brace
Tabs
1 - BEND TABS UP AGAINST TUBE AS SHOWN
21 - 172 AUTOMATIC TRANSMISSION - 42REWJ
VALVE BODY (Continued)
3-4 ACCUMULATOR
(1) Position converter clutch valve and 3-4 shift
valve springs in housing (Fig. 324).
(2) Loosely attach accumulator housing with right-
side screw (Fig. 324). Install only one screw at this
time as accumulator must be free to pivot upward for
ease of installation.
(3) Install 3-4 shift valve and spring.
(4) Install converter clutch timing valve and
spring.
(5) Position plug on end of converter clutch valve
spring. Then compress and hold springs and plug in
place with fingers of one hand.
(6) Swing accumulator housing upward over valve
springs and plug.
(7) Hold accumulator housing firmly in place and
install remaining two attaching screws. Be sure
springs and clutch valve plug are properly seated
(Fig. 325). Tighten screws to 4 N´m (35 in. lbs.).
VALVE BODY FINAL
(1) Install boost valve, valve spring, retainer and
cover plate. Tighten cover plate screws to 4 N´m (35
in. lbs.) torque.
(2) Insert manual lever detent spring in upper
housing.
(3) Position detent ball on end of spring. Then hold
detent ball and spring in detent housing with
Retainer Tool 6583 (Fig. 326).(4) Install throttle lever in upper housing. Then
install manual lever over throttle lever and start
manual lever into housing.
(5) Align manual lever with detent ball and man-
ual valve. Hold throttle lever upward. Then press
down on manual lever until fully seated. Remove
detent ball retainer tool after lever is seated.
(6) Then install manual lever seal, washer and
E-clip.
(7) Verify that throttle lever is aligned with end of
kickdown valve stem and that manual lever arm is
engaged in manual valve (Fig. 327).
(8) Position line pressure adjusting screw in
adjusting screw bracket.
(9) Install spring on end of line pressure regulator
valve.
(10) Install switch valve spring on tang at end of
adjusting screw bracket.
(11) Install manual valve.
(12) Install throttle valve and spring.
(13) Install kickdown valve and detent.
(14) Install pressure regulator valve.
(15) Install switch valve.
(16) Position adjusting screw bracket on valve
body. Align valve springs and press bracket into
place. Install short, upper bracket screws first and
long bottom screw last. Verify that valve springs and
bracket are properly aligned. Then tighten all three
bracket screws to 4 N´m (35 in. lbs.) torque.
(17) Perform Line Pressure and Throttle Pressure
adjustments. (Refer to 21 - TRANSMISSION/TRANS-
AXLE/AUTOMATIC/VALVE BODY - ADJUST-
MENTS)
(18) Lubricate solenoid case connector O-rings and
shaft of manual lever with light coat of petroleum
jelly.
Fig. 324 Converter Clutch And 3-4 Shift Valve
Springs
1 - RIGHT-SIDE SCREW
2 - 3-4 ACCUMULATOR
3 - 3-4 SHIFT VALVE SPRING
4 - CONVERTER CLUTCH VALVE SPRING
Fig. 325 Seating 3-4 Accumulator On Lower
Housing
1 - ACCUMULATOR BOX
2 - CONVERTER CLUTCH VALVE PLUG
WJAUTOMATIC TRANSMISSION - 42RE 21 - 173
VALVE BODY (Continued)
(19) Attach solenoid case connector to 3-4 accumu-
lator with shoulder-type screw. Connector has small
locating tang that fits in dimple at top of accumula-
tor housing (Fig. 328). Seat tang in dimple before
tightening connector screw.
(20) Install solenoid assembly and gasket. Tighten
solenoid attaching screws to 8 N´m (72 in. lbs.)
torque.
(21) Verify that solenoid wire harness is properly
routed (Fig. 329). Solenoid harness must be clear of
manual lever and park rod and not be pinched
between accumulator housing and cover.
Fig. 326 Detent Ball Spring
1 - SPECIAL TOOL 6583 POSITIONED ON DETENT HOUSING
Fig. 327 Manual And Throttle Lever Alignment
1 - THROTTLE LEVER
2 - MANUAL LEVER VALVE ARM
3 - MANUAL VALVE
4 - KICKDOWN VALVE
Fig. 328 Solenoid Harness Case Connector
Shoulder Bolt
1 - SOLENOID HARNESS CASE CONNECTOR
2 - 3-4 ACCUMULATOR HOUSING
Fig. 329 Solenoid Harness Routing
1 - OVERDRIVE/CONVERTER SOLENOID WIRE HARNESS
2 - 3-4 ACCUMULATOR COVER PLATE
21 - 174 AUTOMATIC TRANSMISSION - 42REWJ
VALVE BODY (Continued)