Page 1992 of 2627

(12) Secure detent ball and spring with Retainer
Tool 6583 (Fig. 281).
(13) Remove park rod E-clip and separate rod from
manual lever (Fig. 282).
(14) Remove E-clip and washer that retains throt-
tle lever shaft in manual lever (Fig. 283).
(15) Remove manual lever and throttle lever (Fig.
284). Rotate and lift manual lever off valve body and
throttle lever shaft. Then slide throttle lever out of
valve body.
(16) Position pencil magnet next to detent housing
to catch detent ball and spring. Then carefully
remove Retainer Tool 6583 and remove detent ball
and spring (Fig. 285).
Fig. 281 Detent Ball Spring
1 - SPECIAL TOOL 6583 POSITIONED ON DETENT HOUSING
Fig. 282 Park Rod
1 - MANUAL LEVER
2 - E-CLIP
3 - PARK ROD
Fig. 283 Throttle Lever E-Clip And Washer
1 - THROTTLE LEVER SHAFT
2 - E-CLIP AND WASHER
3 - MANUAL SHAFT
Fig. 284 Manual And Throttle Lever
1 - PARK ROD
2 - MANUAL LEVER ASSEMBLY
3 - THROTTLE LEVER
Fig. 285 Detent Ball And Spring
1 - DETENT HOUSING
2 - DETENT SPRING
3 - DETENT BALL
4 - PENCIL MAGNET
DRAUTOMATIC TRANSMISSION - 48RE 21 - 289
VALVE BODY (Continued)
Page 1993 of 2627

(17) Remove screws attaching pressure adjusting
screw bracket to valve body and transfer plate (Fig.
286). Hold bracket firmly against spring tension
while removing last screw.
(18) Remove adjusting screw bracket, line pressure
adjusting screw, pressure regulator valve spring and
switch valve spring (Fig. 287). Do not remove throttle
pressure adjusting screw from bracket and do not
disturb setting of either adjusting screw during
removal.
(19) Turn upper housing over and remove switch
valve, regulator valve and spring, and manual valve
(Fig. 288).(20) Remove kickdown detent, kickdown valve, and
throttle valve and spring (Fig. 288).
(21) Loosen left-side 3-4 accumulator housing
attaching screw about 2-3 threads. Then remove cen-
ter and right-side housing attaching screws (Fig.
289).
(22) Carefully rotate 3-4 accumulator housing
upward and remove 3-4 shift valve spring and con-
verter clutch valve plug and spring (Fig. 290).
Fig. 287 Adjusting Screw Bracket
1 - SWITCH VALVE SPRING
2 - LINE PRESSURE SCREW
3 - THROTTLE PRESSURE ADJUSTING SCREW
4 - ADJUSTING SCREW BRACKET
5 - PRESSURE REGULATOR VALVE SPRING
Fig. 286 Adjusting Screw Bracket Fastener
1 - T25 TORXŸ BIT
2 - REMOVE THESE SCREWS FIRST
3 - BRACKET
4 - BRACKET
5 - REMOVE THIS SCREW LAST
21 - 290 AUTOMATIC TRANSMISSION - 48REDR
VALVE BODY (Continued)
Page 1994 of 2627
Fig. 288 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
Fig. 289 Accumulator Housing Screw Locations
1 - LOOSEN THIS SCREW
2 - REMOVE THESE SCREWS
3 - 3-4 ACCUMULATOR HOUSINGFig. 290 3-4 Shift And Converter Clutch Valve
Springs and Plug
1 - ACCUMULATOR HOUSING
2 - CONVERTER CLUTCH VALVE SPRING
3 - CLUTCH VALVE PLUG
4 - 3-4 SHIFT VALVE SPRING
DRAUTOMATIC TRANSMISSION - 48RE 21 - 291
VALVE BODY (Continued)
Page 1997 of 2627

VALVE BODY UPPER HOUSING
(1) Note location of check balls in valve body upper
housing (Fig. 299). Then remove the one large diam-
eter and the five smaller diameter check balls.
(2) Remove governor plug and shuttle valve covers
(Fig. 301).
(3) Remove E-clip that secures shuttle valve sec-
ondary spring on valve stem (Fig. 300).
(4) Remove throttle plug, primary spring, shuttle
valve, secondary spring, and spring guides (Fig. 301).
(5) Remove boost valve retainer, spring and valve
if not previously removed.
(6) Remove throttle plug and 1-2 and 2-3 governor
plugs (Fig. 288).
(7) Turn upper housing around and remove limit
valve and shift valve covers (Fig. 302).
(8) Remove limit valve housing. Then remove
retainer, spring, limit valve, and 2-3 throttle plug
from limit valve housing (Fig. 302).
(9) Remove 1-2 shift control valve and spring (Fig.
302).
(10) Remove 1-2 shift valve and spring (Fig. 302).
(11) Remove 2-3 shift valve and spring from valve
body (Fig. 302).
(12) Remove pressure plug cover (Fig. 302).
(13) Remove line pressure sleeve, throttle pressure
plug and spring (Fig. 302).
Fig. 299 Check Ball Locations In Upper Housing
1 - SMALL DIAMETER CHECK BALLS (5)
2 - LARGE DIAMETER CHECK BALL (1)
Fig. 300 Shuttle Valve E-Clip And Secondary Spring
1 - E-CLIP
2 - SECONDARY SPRING AND GUIDES
3 - SHUTTLE VALVE
21 - 294 AUTOMATIC TRANSMISSION - 48REDR
VALVE BODY (Continued)
Page 1998 of 2627
Fig. 301 Shuttle and Boost Valve Location
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
DRAUTOMATIC TRANSMISSION - 48RE 21 - 295
VALVE BODY (Continued)
Page 1999 of 2627
Fig. 302 Upper Housing Shift Valve and Pressure Plug Locations
1 - UPPER HOUSING 7 - LIMIT VALVE AND SPRING
2 - 1-2 SHIFT VALVE AND SPRING 8 - RETAINER
3 - 2-3 SHIFT VALVE AND SPRING 9 - 1-2 SHIFT CONTROL VALVE AND SPRING
4 - 2-3 THROTTLE PLUG 10 - PRESSURE PLUG COVER
5 - LIMIT VALVE HOUSING 11 - PLUG SLEEVE
6 - LIMIT VALVE COVER 12 - THROTTLE PRESSURE SPRING AND PLUG
21 - 296 AUTOMATIC TRANSMISSION - 48REDR
VALVE BODY (Continued)
Page 2001 of 2627

3-4 ACCUMULATOR HOUSING
(1) Remove end plate from housing.
(2) Remove piston spring.
(3) Remove piston. Remove and discard piston
seals (Fig. 304).
CLEANING
Clean the valve housings, valves, plugs, springs,
and separator plates with a standard parts cleaning
solution only. Do not use gasoline, kerosene, or any
type of caustic solution.
Do not immerse any of the electrical components in
cleaning solution. Clean the governor solenoid and
sensor and the dual solenoid and harness assembly
by wiping them off with dry shop towels only.
Dry all except the electrical parts with compressed
air. Make sure all passages are clean and free from
obstructions.Do not use rags or shop towels to
dry or wipe off valve body components. Lint
from these materials can stick to valve body
parts, interfere with valve operation, and clog
filters and fluid passages.
Wipe the governor pressure sensor and solenoid
valve with dry, lint free shop towels only. The O-rings
on the sensor and solenoid valve are the only service-
able components. Be sure the vent ports in the sole-
noid valve are open and not blocked by dirt or debris.
Replace the valve and/or sensor only when DRB scan
tool diagnosis indicates this is necessary. Or, if eitherpart has sustained physical damage (dented,
deformed, broken, etc.).
CAUTION: Do not turn the small screw at the end of
the solenoid valve for any reason. Turning the
screw in either direction will ruin solenoid calibra-
tion and result in solenoid failure. In addition, the
filter on the solenoid valve is NOT serviceable. Do
not try to remove the filter as this will damage the
valve housing.
INSPECTION
Inspect the throttle and manual valve levers and
shafts. Do not attempt to straighten a bent shaft or
correct a loose lever. Replace these components if
worn, bent, loose or damaged in any way.
Inspect all of the valve body mating surfaces for
scratches, nicks, burrs, or distortion. Use a straight-
edge to check surface flatness. Minor scratches may
be removed with crocus cloth using only very light
pressure.
Minor distortion of a valve body mating surface
may be corrected by smoothing the surface with a
sheet of crocus cloth. Position the crocus cloth on a
surface plate, sheet of plate glass or equally flat sur-
face. If distortion is severe or any surfaces are
heavily scored, the valve body will have to be
replaced.
CAUTION: Many of the valves and plugs, such as
the throttle valve, shuttle valve plug, 1-2 shift valve
and 1-2 governor plug, are made of coated alumi-
num. Aluminum components are identified by the
dark color of the special coating applied to the sur-
face (or by testing with a magnet). Do not sand alu-
minum valves or plugs under any circumstances.
This practice could damage the special coating
causing the valves/plugs to stick and bind.
Inspect the valves and plugs for scratches, burrs,
nicks, or scores. Minor surface scratches on steel
valves and plugs can be removed with crocus cloth
butdo not round off the edges of the valve or
plug lands.Maintaining sharpness of these edges is
vitally important. The edges prevent foreign matter
from lodging between the valves and plugs and the
bore.
Inspect all the valve and plug bores in the valve
body. Use a penlight to view the bore interiors.
Replace the valve body if any bores are distorted or
scored. Inspect all of the valve body springs. The
springs must be free of distortion, warpage or broken
coils.
Fig. 304 3-4 Accumulator and Housing
1 - ACCUMULATOR PISTON
2 - 3-4 ACCUMULATOR HOUSING
3 - TEFLON SEALS
4 - PISTON SPRING
5 - COVER PLATE AND SCREWS
21 - 298 AUTOMATIC TRANSMISSION - 48REDR
VALVE BODY (Continued)
Page 2002 of 2627

Check the two separator plates for distortion or
damage of any kind. Inspect the upper housing,
lower housing, 3-4 accumulator housing, and transfer
plate carefully. Be sure all fluid passages are clean
and clear. Check condition of the upper housing and
transfer plate check balls as well. The check balls
and ball seats must not be worn or damaged.
Trial fit each valve and plug in its bore to check
freedom of operation. When clean and dry, the valves
and plugs should drop freely into the bores.
Valve body bores do not change dimensionally with
use. If the valve body functioned correctly when new,
it will continue to operate properly after cleaning and
inspection. It should not be necessary to replace a
valve body assembly unless it is damaged in han-
dling.
The only serviceable valve body components are
listed below. The remaining valve body components
are serviced only as part of a complete valve body
assembly. Serviceable parts are:
²dual solenoid and harness assembly
²solenoid gasket
²solenoid case connector O-rings and shoulder
bolt
²switch valve and spring
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-clipASSEMBLY
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. 305).
(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.
DRAUTOMATIC TRANSMISSION - 48RE 21 - 299
VALVE BODY (Continued)