1998 DODGE RAM 1500 Body

BOOST VALVE TUBE AND BRACE
(1) Position valve body assembly so lower housing
is facing upward (Fig. 318).
(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. 318).
(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. 319).
(6) Install and finger tighten three screws that
secure tube brace to valve body housings (Fig. 319).
(7) Bend tube brace tabs up and against tube to
hold it in position (Fig. 320).
(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. 318 Boost Valve Tube
1 - BOOST VALVE TUBE
2 - LOWER HOUSING
3 - DISENGAGE THIS END OF TUBE FIRST
4 - UPPER HOUSING
Fig. 319 Boost Valve Tube And Brace
1 - BOOST VALVE TUBE
2 - TUBE BRACE
Fig. 320 Securing Boost Valve Tube With Brace
Tabs
1 - BEND TABS UP AGAINST TUBE AS SHOWN
21 - 306 AUTOMATIC TRANSMISSION - 48REDR
VALVE BODY (Continued)

3-4 ACCUMULATOR
(1) Position converter clutch valve and 3-4 shift
valve springs in housing (Fig. 321).
(2) Loosely attach accumulator housing with right-
side screw (Fig. 321). 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. 322). 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. 323).(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.
Fig. 323 Detent Ball Spring
1 - SPECIAL TOOL 6583 POSITIONED ON DETENT HOUSING
Fig. 321 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. 322 Seating 3-4 Accumulator On Lower
Housing
1 - ACCUMULATOR BOX
2 - CONVERTER CLUTCH VALVE PLUG
DRAUTOMATIC TRANSMISSION - 48RE 21 - 307
VALVE BODY (Continued)

(7) Verify that throttle lever is aligned with end of
kickdown valve stem and that manual lever arm is
engaged in manual valve (Fig. 324).
(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.
(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. 325). 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. 326). Solenoid harness must be clear of
manual lever and park rod and not be pinched
between accumulator housing and cover.
Fig. 324 Manual And Throttle Lever Alignment
1 - THROTTLE LEVER
2 - MANUAL LEVER VALVE ARM
3 - MANUAL VALVE
4 - KICKDOWN VALVE
Fig. 325 Solenoid Harness Case Connector
Shoulder Bolt
1 - SOLENOID HARNESS CASE CONNECTOR
2 - 3-4 ACCUMULATOR HOUSING
Fig. 326 Solenoid Harness Routing
1 - OVERDRIVE/CONVERTER SOLENOID WIRE HARNESS
2 - 3-4 ACCUMULATOR COVER PLATE
21 - 308 AUTOMATIC TRANSMISSION - 48REDR
VALVE BODY (Continued)

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. 327). 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.
328).
(3) Check condition of seals on accumulator piston.
Install new piston seals, if necessary.
(4) Place valve body manual lever in low (1 posi-
tion) so ball on park lock rod will be easier to install
in sprag.
(5) Lubricate shaft of manual lever with petroleum
jelly. This will ease inserting shaft through seal in
case.
(6) Lubricate seal rings on valve body harness con-
nector with petroleum jelly.
(7) 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.(8) Install accumulator spring and piston into case.
Then swing valve body over piston and outer spring
to hold it in place.
(9) Align accumulator piston and outer spring,
manual lever shaft and electrical connector in case.
(10) Then seat valve body in case and install one
or two bolts to hold valve body in place.
(11) Tighten valve body bolts alternately and
evenly to 11 N´m (100 in. lbs.) torque.
(12) Install new fluid filter on valve body. Tighten
filter screws to 4 N´m (35 in. lbs.) torque.
(13) Install throttle and gearshift levers on valve
body manual lever shaft.
(14) Check and adjust front and rear bands if nec-
essary.
(15) Install the transmission range sensor (Refer
to 21 - TRANSMISSION/AUTOMATIC/TRANSMIS-
SION RANGE SENSOR - INSTALLATION).
(16) Connect solenoid case connector wires.
(17) Install oil pan and new gasket. Tighten pan
bolts to 13.6 N´m (125 in. lbs.) torque.
(18) Lower vehicle and fill transmission with
MopartATF +4, Automatic Transmission fluid.
(19) Check and adjust gearshift and throttle valve
cables, if necessary.
Fig. 327 Valve Body Harness Connector O-Ring Seal
1 - CONNECTOR O-RINGS
2 - VALVE BODY HARNESS CONNECTOR
3 - HARNESS
DRAUTOMATIC TRANSMISSION - 48RE 21 - 309
VALVE BODY (Continued)

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. 329).
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.THROTTLE PRESSURE ADJUSTMENT
Insert Gauge Tool C-3763 between the throttle
lever cam and the kickdown valve stem (Fig. 330).
Push the gauge tool inward to compress the kick-
down valve against the spring and bottom the throt-
tle valve.
Maintain pressure against kickdown valve spring.
Turn throttle lever stop screw until the screw head
touches throttle lever tang and the throttle lever cam
touches gauge tool.
NOTE: The kickdown valve spring must be fully
compressed and the kickdown valve completely
bottomed to obtain correct adjustment.
Fig. 328 Manual Lever Shaft Seal
1 - 15/1688SOCKET
2 - SEALFig. 329 Line Pressure Adjustment
1 - WRENCH
2 - 1±5/16 INCH
Fig. 330 Throttle Pressure Adjustment
1 - HEX WRENCH (IN THROTTLE LEVER ADJUSTING SCREW)
2 - SPECIAL TOOL C-3763 (POSITIONED BETWEEN THROTTLE
LEVER AND KICKDOWN VALVE)
21 - 310 AUTOMATIC TRANSMISSION - 48REDR
VALVE BODY (Continued)

INSTALLATION........................391
OUTPUT SPEED SENSOR
DESCRIPTION........................391
OPERATION..........................391
REMOVAL............................391
INSTALLATION........................392
TOW/HAUL OVERDRIVE SWITCH
DESCRIPTION........................392
OPERATION..........................392
REMOVAL............................392
INSTALLATION........................393
PISTONS
DESCRIPTION........................393
OPERATION..........................393
PLANETARY GEARTRAIN
DESCRIPTION........................395
OPERATION..........................396
DISASSEMBLY........................396
CLEANING...........................396
INSPECTION.........................397
ASSEMBLY...........................397
SHIFT MECHANISM
DESCRIPTION........................398
OPERATION..........................398
SOLENOID SWITCH VALVE
DESCRIPTION........................398
OPERATION..........................398
SOLENOIDS
DESCRIPTION........................398OPERATION..........................399
TORQUE CONVERTER
DESCRIPTION........................399
OPERATION..........................403
REMOVAL............................404
INSTALLATION........................404
TRANSMISSION CONTROL RELAY
DESCRIPTION........................405
OPERATION..........................405
TRANSMISSION RANGE SENSOR
DESCRIPTION........................405
OPERATION..........................405
TRANSMISSION SOLENOID/TRS ASSEMBLY
DESCRIPTION........................406
OPERATION..........................406
REMOVAL............................407
INSTALLATION........................408
TRANSMISSION TEMPERATURE SENSOR
DESCRIPTION........................408
OPERATION..........................408
VALVE BODY
DESCRIPTION........................408
OPERATION..........................408
REMOVAL............................410
DISASSEMBLY........................410
CLEANING...........................412
INSPECTION.........................413
ASSEMBLY...........................414
INSTALLATION........................414
AUTOMATIC TRANSMISSION -
45RFE/545RFE
DESCRIPTION
The 45RFE/545RFE automatic transmissions is a
sophisticated, multi-range, electronically controlled
transmission which combines optimized gear ratios
for responsive performance, state of the art efficiency
features and low NVH. Other features include driver
adaptive shifting and three planetary gear sets to
provide wide ratio capability with precise ratio steps
for optimum driveability. The three planetary gear
sets also make available a unique alternate second
gear ratio. The primary 2nd gear ratio fits between
1st and 3rd gears for normal through-gear accelera-
tions. The alternate second gear ratio (2prime) allows
smoother 4-2 kickdowns at high speeds to provide
2nd gear passing performance over a wider highway
cruising range.
The hydraulic portion of the transmission consists
of the transmission fluid, fluid passages, hydraulic
valves, and various line pressure control components.The primary mechanical components of the trans-
mission consist of the following:
²Three multiple disc input clutches
²Three multiple disc holding clutches
²Five hydraulic accumulators
²Three planetary gear sets
²Dual Stage Hydraulic oil pump
²Valve body
²Solenoid pack
The TCM is the ªheartº or ªbrainº of the electronic
control system and relies on information from vari-
ous direct and indirect inputs (sensors, switches, etc.)
to determine driver demand and vehicle operating
conditions. With this information, the TCM can cal-
culate and perform timely and quality shifts through
various output or control devices (solenoid pack,
transmission control relay, etc.).
21 - 312 AUTOMATIC TRANSMISSION - 45RFE/545RFEDR

DIAGNOSIS AND TESTING - HYDRAULIC
PRESSURE TEST
An accurate tachometer and pressure test gauges
are required. Test Gauge C-3293-SP has a 300 psi
range and is used at all locations where pressures
exceed 100 psi.
Pressure Test Port Locations
Only two pressure ports are supplied on the trans-
mission case. The torque converter clutch apply and
release ports are located on the right side of the
transmission case (Fig. 2).
To determine the line pressure, there are two avail-
able methods. The DRBtscan tool can be used to
read line pressure from the line pressure sensor. The
second method is to install Line Pressure Adapter
8259 (Fig. 4) into the transmission case and then
install the pressure gauge and the original sensor
into the adapter. This will allow a comparison of the
DRBtreadings and the gauge reading to determine
the accuracy of the line pressure sensor. The DRBt
line pressure reading should match the gauge read-
ing within  10 psi.
In order to access any other pressure tap locations,
the transmission oil pan must be removed, the pres-
sure port plugs removed and Valve Body Pressure
Tap Adapter 8258-A (Fig. 5) installed. The extensions
supplied with Adapter 8258-A will allow the installa-
tion of pressure gauges to the valve body. Refer to
(Fig. 3) for correct pressure tap location identifica-
tion.
TEST PROCEDURE
All pressure readings should be taken with the
transmission fluid level full, transmission oil at the
normal operating temperature, and the engine at
1500 rpm. Check the transmission for proper opera-
tion in each gear position that is in question or if a
specific element is in question, check the pressure
readings in at least two gear positions that employ
that element. Refer to the Hydraulic Schematics at
the rear of this section to determine the correct pres-
sures for each element in a given gear position.
Fig. 2 Torque Converter Pressure Locations
1 - TCC RELEASE
2 - TO COOLER
3 - TCC APPLY
4 - FROM COOLER
5 - LINE PRESSURE SENSOR
Fig. 3 Pressure Tap Locations
Fig. 4 Line Pressure Adapter 8259
1 - LINE PRESSURE SENSOR PORT
2 - LINE PRESSURE SENSOR
3 - TOOL 8259
4 - PRESSURE TAP
21 - 316 AUTOMATIC TRANSMISSION - 45RFE/545RFEDR
AUTOMATIC TRANSMISSION - 45RFE/545RFE (Continued)

NOTE: The 45RFE/545RFE utilizes closed loop con-
trol of pump line pressure. The pressure readings
may therefore vary greatly but should always follow
line pressure.
Some common pressures that can be measured to
evaluate pump and clutch performance are the
upshift/downshift pressures, garage shift pressures,
and TCC pressure. The upshift/downshift pressure
for all shifts are shown in UPSHIFT PRESSURES
and DOWNSHIFT PRESSURES. In-gear maximum
pressure for each gear position is shown in IN-GEAR
PRESSURES. The garage shift pressure when per-
forming a N-R shift is 220 psi for 3.7L/4.7L equipped
vehicles and 250 psi for 5.7L equipped vehicles. The
garage shift pressure for the R-N shift is 120 psi. The
garage shift pressure for the N-1 shift is 135 psi for
3.7L/4.7L equipped vehicles and 165 psi for 5.7L
equipped vehicles. Torque converter lock-up pressure
is 120 psi for 3.7L/4.7L equipped vehicles and 125 psi
for 5.7L equipped vehicles.
UPSHIFT PRESSURES
ENGINE 1-2 2-3 2prime-3 3-4 2prime-4 2-5 3-5 4-5
5.7L150 125 125 135 135 135 135 135
3.7L/
4.7L120 120 120 120 120 120 120 130
DOWNSHIFT PRESSURES
ENG-
INE5-
45-3 5-2 4-34-2
prime3-23-2
prime2
prime-
12-
13-1
5.7L135 135 135 135 135 135 135 135 135 135
3.7L/
4.7L120 120 120 120 120 120 120 120 120 120
IN-GEAR PRESSURES
ENGINE 1 22
prime345NEUT-
RALREV-
ERSE
5.7L160 135 135 135 135 135 120 250
3.7L/
4.7L135 120 120 120 120 120 120 220
DIAGNOSIS AND TESTING - AIR CHECKING
TRANSMISSION CLUTCH OPERATION
Air-pressure testing can be used to check transmis-
sion clutch operation. The test can be conducted with
the transmission either in the vehicle or on the work
bench, as a final check.
Air-pressure testing requires that the oil pan and
valve body be removed from the transmission. The
clutch apply passages are shown (Fig. 6).
NOTE: The air supply which is used must be free of
moisture and dirt. Use a pressure of 30 psi to test
clutch operation.
Apply air pressure at each port. If the clutch is
functioning, a soft thump will be heard as the clutch
Fig. 5 Valve Body Pressure Tap Adapter 8258-A
1 - 45RFE TRANSMISSION
2 - TOOL 8258-A
Fig. 6 Air Pressure Test Passages
1 - LOW REVERSE CLUTCH
2 - 4TH CLUTCH
3 - 2ND CLUTCH
4 - OVERDRIVE CLUTCH
5 - UNDERDRIVE CLUTCH
6 - REVERSE CLUTCH
DRAUTOMATIC TRANSMISSION - 45RFE/545RFE 21 - 317
AUTOMATIC TRANSMISSION - 45RFE/545RFE (Continued)