2003 DODGE RAM automatic transmission fluid

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 either
part 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, thefilter 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.
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.
Fig. 322 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 - 46REDR
VALVE BODY (Continued)

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-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. 321).
(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.
322).
(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. 323).
(2) Install filter screen in upper housing separator
plate (Fig. 324).
Fig. 323 Rear Clutch And Rear Servo Check Ball
Locations
1 - REAR CLUTCH CHECK BALL
2 - REAR SERVO CHECK BALL
3 - TRANSFER PLATE
Fig. 324 Separator Plate Filter Screen Installation
1 - UPPER HOUSING SEPARATOR PLATE
2 - FILTER SCREEN
DRAUTOMATIC TRANSMISSION - 46RE 21 - 299
VALVE BODY (Continued)

(4) Position lower housing separator plate on
transfer plate (Fig. 329).
(5) Install lower housing on assembled transfer
plate and upper housing (Fig. 330).
(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. 330).UPPER HOUSING VALVE AND PLUG
Refer to (Fig. 331), (Fig. 332) and (Fig. 333) 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.
(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. 329 Lower Housing Separator Plate
1 - BE SURE TO ALIGN BORES
2 - TRANSFER PLATE
3 - LOWER HOUSING (OVERDRIVE) SEPARATOR PLATE
Fig. 330 Installing Lower Housing On Transfer Plate
And Upper Housing
1 - VALVE BODY SCREWS (13)
2 - LOWER HOUSING
3 - UPPER HOUSING
4 - TRANSFER PLATE
DRAUTOMATIC TRANSMISSION - 46RE 21 - 301
VALVE BODY (Continued)

BOOST VALVE TUBE AND BRACE
(1) Position valve body assembly so lower housing
is facing upward (Fig. 334).
(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. 334).
(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. 335).
(6) Install and finger tighten three screws that
secure tube brace to valve body housings (Fig. 335).
(7) Bend tube brace tabs up and against tube to
hold it in position (Fig. 336).
(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. 333 Upper Housing Shift Valve and Pressure Plug Locations
1 - UPPER HOUSING 8 - RETAINER
2 - 1-2 SHIFT VALVE AND SPRING 9 - 1-2 SHIFT CONTROL VALVE AND SPRING
3 - 2-3 SHIFT VALVE AND SPRING 10 - PRESSURE PLUG COVER
4 - 2-3 THROTTLE PLUG 11 - LINE PRESSURE PLUG
5 - LIMIT VALVE HOUSING 12 - PLUG SLEEVE
6 - LIMIT VALVE COVER 13 - THROTTLE PRESSURE SPRING AND PLUG
7 - LIMIT VALVE AND SPRING
Fig. 334 Boost Valve Tube
1 - BOOST VALVE TUBE
2 - LOWER HOUSING
3 - DISENGAGE THIS END OF TUBE FIRST
4 - UPPER HOUSING
21 - 304 AUTOMATIC TRANSMISSION - 46REDR
VALVE BODY (Continued)

(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. 342). Solenoid harness must be clear of
manual lever and park rod and not be pinched
between accumulator housing and cover.
GOVERNOR BODY, SENSOR AND SOLENOID
(1) Turn valve body assembly over so accumulator
side of transfer plate is facing down.
(2) Install new O-rings on governor pressure sole-
noid and sensor.
(3) Lubricate solenoid and sensor O-rings with
clean transmission fluid.
(4) Install governor pressure sensor in governor
body.
(5) Install governor pressure solenoid in governor
body. Push solenoid in until it snaps into place in
body.
(6) Position governor body gasket on transfer
plate.
(7) Install retainer plate on governor body and
around solenoid. Be sure solenoid connector is posi-
tioned in retainer cutout.
(8) Align screw holes in governor body and trans-
fer plate. Then install and tighten governor body
screws to 4 N´m (35 in. lbs.) torque.
(9) Connect harness wires to governor pressure
solenoid and governor pressure sensor.
(10) Install fluid filter and pan.(11) Lower vehicle.
(12) Fill transmission with recommended fluid and
road test vehicle to verify repair.
INSTALLATION
(1) Check condition of O-ring seals on valve body
harness connector (Fig. 343). Replace seals on con-
nector body if cut or worn.
(2) Check condition of manual lever shaft seal in
transmission case. Replace seal if lip is cut or worn.
Install new seal with 15/16 deep well socket (Fig.
344).
(3) Check condition of seals on accumulator piston.
Install new piston seals, if necessary.
(4) Verify that transmission range sensor isNOT
installed. Valve body cannot be installed with sensor
in place.
(5) Place valve body manual lever in low (1 posi-
tion) so ball on park lock rod will be easier to install
in sprag.
(6) Lubricate shaft of manual lever with petroleum
jelly. This will ease inserting shaft through seal in
case.
(7) Lubricate seal rings on valve body harness con-
nector with petroleum jelly.
(8) Position valve body in case and work end of
park lock rod into and through pawl sprag. Turn pro-
peller shaft to align sprag and park lock teeth if nec-
essary. The rod will click as it enters pawl. Move rod
to check engagement.
CAUTION: It is possible for the park rod to displace
into a cavity just above the pawl sprag during
installation. Make sure the rod is actually engaged
in the pawl and has not displaced into this cavity.
(9) Install accumulator spring and piston into case.
Then swing valve body over piston and outer spring
to hold it in place.
(10) Align accumulator piston and outer spring,
manual lever shaft and electrical connector in case.
(11) Then seat valve body in case and install one
or two bolts to hold valve body in place.
(12) Tighten valve body bolts alternately and
evenly to 11 N´m (100 in. lbs.) torque.
(13) Install new fluid filter on valve body. Tighten
filter screws to 4 N´m (35 in. lbs.) torque.
(14) Install throttle and gearshift levers on valve
body manual lever shaft.
Fig. 342 Solenoid Harness Routing
1 - OVERDRIVE/CONVERTER SOLENOID WIRE HARNESS
2 - 3-4 ACCUMULATOR COVER PLATE
DRAUTOMATIC TRANSMISSION - 46RE 21 - 307
VALVE BODY (Continued)

(15) Check and adjust front and rear bands if nec-
essary.
(16) Connect solenoid case connector wires.
(17) Install the transmission range sensor.
(18) Install oil pan and new gasket. Tighten pan
bolts to 17 N´m (13 ft. lbs.) torque.
(19) Lower vehicle and fill transmission with
MopartATF +4, Automatic Transmission fluid.
(20) Check and adjust gearshift and throttle valve
cables, if necessary.ADJUSTMENTS - VALVE BODY
CONTROL PRESSURE ADJUSTMENTS
There are two control pressure adjustments on the
valve body;
²Line Pressure
²Throttle Pressure
Line and throttle pressures are interdependent
because each affects shift quality and timing. As a
result, both adjustments must be performed properly
and in the correct sequence. Adjust line pressure first
and throttle pressure last.
LINE PRESSURE ADJUSTMENT
Measure distance from the valve body to the inner
edge of the adjusting screw with an accurate steel
scale (Fig. 345).
Distance should be 33.4 mm (1-5/16 in.).
If adjustment is required, turn the adjusting screw
in, or out, to obtain required distance setting.
NOTE: The 33.4 mm (1-5/16 in.) setting is an
approximate setting. Manufacturing tolerances may
make it necessary to vary from this dimension to
obtain desired pressure.
One complete turn of the adjusting screw changes
line pressure approximately 1-2/3 psi (9 kPa).
Turning the adjusting screw counterclockwise
increases pressure while turning the screw clockwise
decreases pressure.
Fig. 343 Valve Body Harness Connector O-Ring Seal
1 - CONNECTOR O-RINGS
2 - VALVE BODY HARNESS CONNECTOR
3 - HARNESS
Fig. 344 Manual Lever Shaft Seal
1 - 15/1688SOCKET
2 - SEAL
Fig. 345 Line Pressure Adjustment
1 - WRENCH
2 - 1±5/16 INCH
21 - 308 AUTOMATIC TRANSMISSION - 46REDR
VALVE BODY (Continued)

AUTOMATIC TRANSMISSION - 48RE
TABLE OF CONTENTS
page page
AUTOMATIC TRANSMISSION - 48RE
DESCRIPTION........................312
OPERATION..........................314
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - AUTOMATIC
TRANSMISSION.....................320
DIAGNOSIS AND TESTING - PRELIMINARY. . 320
DIAGNOSIS AND TESTING - ROAD
TESTING...........................320
DIAGNOSIS AND TESTING - HYDRAULIC
PRESSURE TEST....................321
DIAGNOSIS AND TESTING - AIR TESTING
TRANSMISSION CLUTCH AND BAND
OPERATION........................324
DIAGNOSIS AND TESTING - CONVERTER
HOUSING FLUID LEAK................324
DIAGNOSIS AND TESTING - DIAGNOSIS
CHARTS...........................325
STANDARD PROCEDURE - ALUMINUM
THREAD REPAIR.....................337
REMOVAL............................337
DISASSEMBLY........................339
CLEANING...........................345
INSPECTION.........................345
ASSEMBLY...........................346
INSTALLATION........................353
SCHEMATICS AND DIAGRAMS
HYDRAULIC SCHEMATICS.............355
SPECIFICATIONS
TRANSMISSION.....................368
SPECIAL TOOLS
RE TRANSMISSION..................370
ACCUMULATOR
DESCRIPTION........................372
OPERATION..........................373
INSPECTION.........................373
BANDS
DESCRIPTION........................373
OPERATION..........................374
ADJUSTMENTS
ADJUSTMENT - BANDS...............374
BRAKE TRANSMISSION SHIFT INTERLOCK
SYSTEM
DESCRIPTION........................375
OPERATION..........................375
DIAGNOSIS AND TESTING - BRAKE
TRANSMISSION SHIFT INTERLOCK......375
ADJUSTMENTS - BRAKE TRANSMISSION
SHIFT INTERLOCK...................376ELECTRONIC GOVERNOR
DESCRIPTION........................376
OPERATION..........................377
REMOVAL............................378
INSTALLATION........................379
EXTENSION HOUSING SEAL
REMOVAL............................380
INSTALLATION........................380
FLUID AND FILTER
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - EFFECTS OF
INCORRECT FLUID LEVEL.............381
DIAGNOSIS AND TESTING - CAUSES OF
BURNT FLUID.......................381
DIAGNOSIS AND TESTING - FLUID
CONTAMINATION....................381
STANDARD PROCEDURE
STANDARD PROCEDURE - FLUID LEVEL
CHECK............................381
STANDARD PROCEDURE - FLUID AND
FILTER REPLACEMENT...............383
STANDARD PROCEDURE - TRANSMISSION
FILL...............................383
FRONT CLUTCH
DESCRIPTION........................384
OPERATION..........................384
DISASSEMBLY........................384
INSPECTION.........................385
ASSEMBLY...........................386
FRONT SERVO
DESCRIPTION........................387
OPERATION..........................387
DISASSEMBLY........................388
CLEANING...........................388
INSPECTION.........................388
ASSEMBLY...........................388
GEARSHIFT CABLE
DIAGNOSIS AND TESTING - GEARSHIFT
CABLE.............................389
REMOVAL............................389
INSTALLATION........................390
ADJUSTMENTS
GEARSHIFT CABLE..................391
OIL PUMP
DESCRIPTION........................392
OPERATION..........................392
DISASSEMBLY........................393
CLEANING...........................393
INSPECTION.........................393
ASSEMBLY...........................393
21 - 310 AUTOMATIC TRANSMISSION - 48REDR

AUTOMATIC TRANSMISSION -
48RE
DESCRIPTION
The 48RE (Fig. 1) is a four speed fully automatic
transmission with an electronic governor. The 48RE
is equipped with a lock-up clutch in the torque con-
verter. First through third gear ranges are provided
by the clutches, bands, overrunning clutch, and plan-
etary gear sets in the transmission. Fourth gear
range is provided by the overdrive unit that contains
an overdrive clutch, direct clutch, planetary gear set,
and overrunning clutch.
The transmission contains a front, rear, and direct
clutch which function as the input driving compo-
nents. It also contains the kickdown (front) and thelow/reverse (rear) bands which, along with the over-
running clutch and overdrive clutch, serve as the
holding components. The driving and holding compo-
nents combine to select the necessary planetary gear
components, in the front, rear, or overdrive planetary
gear set, transfer the engine power from the input
shaft through to the output shaft.
The valve body is mounted to the lower side of the
transmission and contains the valves to control pres-
sure regulation, fluid flow control, and clutch/band
application. The oil pump is mounted at the front of
the transmission and is driven by the torque con-
verter hub. The pump supplies the oil pressure nec-
essary for clutch/band actuation and transmission
lubrication.
21 - 312 AUTOMATIC TRANSMISSION - 48REDR