1998 DODGE RAM 1500 Valve

(11) Remove the retainer ring set screw from the
valve housing (Fig. 12).
(12) Using special tool reatainer ring wrench to
remove the steering gear worm thrust bearing
reatainer ring (Fig. 13).(13) Separate the wormshaft assembly from the
valve housing, Then remove the wormshaft assembly
from the vise (Fig. 14).
(14) Remove the dust seal with a pick (Fig. 15).
Fig. 12 SET SCREW FOR THE RETAINER RING
1 - SET SCREW
2 - 3/32 ALLEN HEAD SOCKET
3 - RETAINER RING
Fig. 13 REATINER RING REMOVAL
1 - SPECIAL TOOL
8988
2 - RATCHET
Fig. 14 WORMSHAFT AND VALVE ASSEMBLY
1 - PISTON TEFLON SEALS
2 - RETAINER RING
Fig. 15 DUST SEAL REMOVAL
1 - PICK
2 - VALVE HOUSING
3 - SEAL
19 - 28 GEAR - LINK/COILDR
STEERING GEAR INPUT SHAFT SEAL (Continued)

CAUTION: Use care not to score the housing bore
when removing seals.
(15) Remove the snap ring with snap ring pliers
(Fig. 16).
(16) Using special tool slide hammer C-3752 with
adapter 8990 remove the oil seal (Fig. 17).
INSTALLATION
(1) Inspect the piston teflon seals for damage.
Replace if needed.
NOTE: To replace the teflon seals, use a pick to
remove the teflon o-ring and the rubber o-ringunderneath. Install a new rubber o-ring in the piston
seal grove and a new teflon o-ring over the top of it.
(2) Install the valve into the valve housing.
(3) Thread the retainer ring into the valve housing
(Fig. 18). Tighten to 97 N´m (72 ft. lbs.)
NOTE: It is very important to make sure to compen-
sate for the added length of the torque wrench
when torquing to proper specifications.
(4) Install the retainer ring set screw. Tighten to
2.26 N´m (20 in. lbs.)
(5) Clean the steering gear housing.
CAUTION: Valve assembly must be centered to the
housing (Fig. 19).
(6) Install the valve assembly into the steering
gear (Fig. 19). Tighten the new bolts to 54 N´m (40 ft.
lbs.)
Fig. 16 SNAP RING REMOVAL
1 - SNAP RING PLIERS
2 - SNAP RING
3 - VALVE HOUSING
Fig. 17 OIL SEAL REMOVAL
1 - SPECIAL TOOL
8990
WITH SLIDE HAMMER C-3752
2 - VALVE HOUSING
Fig. 18 RETAINER RING INSTALLATION
1 - VALVE HOUSING
2 - SPECIAL TOOL
3 - TORQUE WRENCH
Fig. 19 CENTERED GEAR TEETH
1 - GEAR INSTALLED WITH THE CENTER TOOTH CENTERED IN
HOLE
2 - VALVE HOUSING
DRGEAR - LINK/COIL 19 - 29
STEERING GEAR INPUT SHAFT SEAL (Continued)

(7) Install the input shaft seal protector 8986 (Fig.
20).
(8) Coat the new seal inhigh temp greaseand
Install the new oil seal using special tool 8987 driver
and C-4171 handle (Fig. 21).
NOTE: Drive the oil seal into the housing until the
outer edge does not quite clear the snap ring
groove.
(9) Insert the snap ring into the housing. Using
special tool 8987 driver and C-4171 handle push the
snap ring and oil seal together until the snap ring
seats in the groove.NOTE: Generous amounts of the high temperature
grease from the seal kit should be applied to areas
between the pitman shaft bearing and oil seals and
also between the dust seals and snap ring.
(10) Install the new dust seal usinghigh temp
grease, special tool C-4171 (driver) and 8987 (han-
dle).
(11) Check to make sure the gear is centered in
the middle tooth before installing the pitman shaft
(Fig. 19).
(12) Install the pitman shaft into the steering gear
(Refer to 19 - STEERING/GEAR/PITMAN SHAFT -
INSTALLATION).
(13) Perform over-center meshload adjustment
(Refer to 19 - STEERING/GEAR - ADJUSTMENTS).
(14) Install the steering gear to the vehicle (Refer
to 19 - STEERING/GEAR - INSTALLATION).
(15) Perform a wheel alignment (Refer to 2 - SUS-
PENSION/WHEEL ALIGNMENT - STANDARD
PROCEDURE).
PITMAN SHAFT
REMOVAL
REMOVAL - GAS
(1) Separate the pitman arm from the gear box
(Refer to 19 - STEERING/LINKAGE/PITMAN ARM -
REMOVAL).
(2) Clean exposed end of pitman shaft and housing
with a wire brush.
(3) Rotate the steering wheel from stop to stop and
count the number of turns.
(4) Center the steering wheel by rotating it from
the stop back 1 1/2 turns to achieve center position.
(5) Remove the pitman shaft cover bolts.
NOTE: The pitman shaft will not clear the housing if
it is not centered.
(6) Remove the pitman shaft from the gear (Fig.
22).
(7) Remove the cover if needed by loosing the
adjuster nut, Then removing the cover from the pit-
man shaft.
REMOVAL - DIESEL
(1) Separate the pitman arm from the gear box
(Refer to 19 - STEERING/LINKAGE/PITMAN ARM -
REMOVAL).
(2) Remove the steering gear box (Refer to 19 -
STEERING/GEAR - REMOVAL).
(3) Install the steering gear in a soft jawed bench
vise.
Fig. 20 INPUT SHAFT SEAL PROTECTOR
1 - INPUT SHAFT
2 - SPECIAL TOOL 8986
Fig. 21 INPUT SHAFT SEAL INSTALLATION
1 - VALVE HOUSING
2 - SPECIAL TOOL 8987
3 - SPECIAL TOOL C-4171
19 - 30 GEAR - LINK/COILDR
STEERING GEAR INPUT SHAFT SEAL (Continued)

OPERATION
Hydraulic pressure is provided for the power steer-
ing gear by the belt driven power steering pump (Fig.
1). The power steering pumps are constant flow rate
and displacement, vane-type pumps.
DIAGNOSIS AND TESTING - PUMP LEAKAGE
The pump is serviced as an assembly and should
not be disassembled. The plastic pump reservoir and
the reservoir o-rings can be replaced.
Check for leaks in the following areas:
²Pump shaft seal behind the pulley
²Pump to reservoir O-ring
²Reservoir cap
²Pressure and return lines
²Flow control valve fitting
STANDARD PROCEDURE
STANDARD PROCEDURE - POWER STEERING
PUMP - INITIAL OPERATION
WARNING: THE FLUID LEVEL SHOULD BE
CHECKED WITH ENGINE OFF TO PREVENT INJURY
FROM MOVING COMPONENTS.
CAUTION: MOPARTATF+4 is to be used in the
power steering system. No other power steering or
automatic transmission fluid is to be used in the
system. Damage may result to the power steeringpump and system if any other fluid is used, and do
not overfill.
Wipe filler cap clean, then check the fluid level.
The dipstick should indicateCOLDwhen the fluid is
at normal temperature.
(1) Turn steering wheel all the way to the left
(2) Fill the pump fluid reservoir to the proper level
and let the fluid settle for at least two (2) minutes.
(3) Raise the front wheels off the ground.
(4) Slowly turn the steering wheel lock-to-lock 20
times with the engine off while checking the fluid
level.
NOTE: For vehicles with long return lines or oil
coolers turn wheel 40 times.
(5) Start the engine. With the engine idling main-
tain the fluid level.
(6) Lower the front wheels and let the engine idle
for two minutes.
(7) Turn the steering wheel in both direction and
verify power assist and quiet operation of the pump.
If the fluid is extremely foamy or milky looking,
allow the vehicle to stand a few minutes and repeat
the procedure.
CAUTION: Do not run a vehicle with foamy fluid for
an extended period. This may cause pump damage.
STANDARD PROCEDURE - FLUSHING POWER
STEERING SYSTEM
Flushing is required when the power steering/hy-
draulic booster system fluid has become contami-
nated. Contaminated fluid in the steering/booster
system can cause seal deterioration and affect steer-
ing gear/booster spool valve operation.
(1) Raise the front end of the vehicle off the
ground until the wheels are free to turn.
(2) Remove the return line from the pump.
NOTE: If vehicle is equipped with a hydraulic
booster remove both return lines from the pump.
(3) Plug the return line port/ports at the pump.
(4) Position the return line/lines into a large con-
tainer to catch the fluid.
(5) While an assistant is filling the pump reservoir
start the engine.
(6) With the engine running at idle turn the wheel
back and forth.
NOTE: Do not contact or hold the wheel against the
steering stops.
(7) Run a quart of fluid through the system then
stop the engine and install the return line/lines.
Fig. 1 POWER STEERING PUMP
1 - 3.7L & 4.7L (6 GROOVE)
PHENOLIC (PLASTIC TYPE) PULLEY
1 - 5.7L,5.9L & 8.0L (7 GROOVE)
PHENOLIC (PLASTIC TYPE) PULLEY
1 - 5.9L DIESEL (8 GROOVE)
STEEL PULLEY
2 - PUMP ASSEMBLY
3 - RESERVOIR
4 - CAP
19 - 40 PUMPDR
PUMP (Continued)

(8) Fill the system with fluid and perform Steering
Pump Initial Operation, (Refer to 19 - STEERING/
PUMP - STANDARD PROCEDURE).
(9) Start the engine and run it for fifteen minutes
then stop the engine.
(10) Remove the return line/lines from the pump
and plug the pump port/ports.
(11) Pour fresh fluid into the reservoir and check
the draining fluid for contamination. If the fluid is
still contaminated, then flush the system again.
(12) Install the return line/lines and perform
Steering Pump Initial Operation, (Refer to 19 -
STEERING/PUMP - STANDARD PROCEDURE).
REMOVAL
REMOVAL - GAS
(1) Drain and siphon the power steering fluid from
the reservoir.
(2) Remove the serpentine belt.
CAUTION: Do not remove the fitting on the pump
that the high pressure hose screws into. The fitting
may come loose unless it is backed up using
another wrench. If the fitting does come loose, it
must be retightened before continuing. (57 - 67Nm,
40 - 50 lbft) If this fitting comes out of the pump
body, the internal spring and valve parts will fall out
of the pump and they cannot be reinstalled prop-
erly. If this occurs the pump needs to be replaced
with a new pump.
(3) Disconnect the return hose. (Fig. 2)
(4) Disconnect the pressure hose. (Fig. 2)
(5) Access to remove the three bolts securing the
pump to the cylinder head can be gained thru the
pulley holes. (Fig. 2)
REMOVAL - DIESEL
(1) Drain and siphon the power steering fluid from
the reservoir.
(2) Remove the serpentine belt.
CAUTION: Do not remove the fitting on the pump
that the high pressure hose screws into. The fitting
may come loose unless it is backed up using
another wrench. If the fitting does come loose, it
must be retightened before continuing. (57 - 67Nm,
40 - 50 lbft) If this fitting comes out of the pump
body, the internal spring and valve parts will fall out
of the pump and they cannot be reinstalled prop-
erly. If this occurs the pump needs to be replaced
with a new pump.
(3) Disconnect the return hose.
(4) Disconnect the pressure hose.(5) Access to remove the three bolts securing the
pump to the cylinder head can be gained thru the
pulley holes.
(6) Loosen the pump bracket to the block.
(7) Remove the 6 intake plenum bolts (Fig. 3).
(8) loosen the inner cooler tube clamp at the
intake plenum and remove the intake plenum.
(9) Loosen the inner cooler tube clamp at the radi-
ator support side and remove the tube from the vehi-
cle.
(10) Remove the power steering pump from the top
of the engine compartment where the intake plenum
was (Fig. 3).
Fig. 2 POWER STEERING PUMP
1 - POWER STEERING PULLEY
2 - POWER STEERING RESERVOIR
3 - RETURN HOSE
4 - HIGH PRESSURE HOSE
Fig. 3 POWER STEERING PUMP ACCESS
1 - INTAKE PLENUM MOUNTING
2 - POWER STEERING PUMP
DRPUMP 19 - 41
PUMP (Continued)

OUTPUT SHAFT FRONT BEARING
REMOVAL............................216
INSTALLATION........................216
OUTPUT SHAFT REAR BEARING
REMOVAL............................216
INSTALLATION........................217
OVERDRIVE CLUTCH
DESCRIPTION........................217
OPERATION..........................217
OVERDRIVE UNIT
REMOVAL............................218
DISASSEMBLY........................218
CLEANING...........................225
INSPECTION.........................225
ASSEMBLY...........................226
INSTALLATION........................235
OVERRUNNING CLUTCH CAM/OVERDRIVE
PISTON RETAINER
DESCRIPTION........................236
OPERATION..........................236
DISASSEMBLY........................236
CLEANING...........................236
INSPECTION.........................237
ASSEMBLY...........................237
PISTONS
DESCRIPTION........................239
OPERATION..........................239
PLANETARY GEARTRAIN/OUTPUT SHAFT
DESCRIPTION........................241
OPERATION..........................241
DISASSEMBLY........................242
INSPECTION.........................243
ASSEMBLY...........................244
REAR CLUTCH
DESCRIPTION........................247
OPERATION..........................248
DISASSEMBLY........................248
CLEANING...........................248
INSPECTION.........................248
ASSEMBLY...........................249
REAR SERVO
DESCRIPTION........................251
OPERATION..........................251
DISASSEMBLY........................251
CLEANING...........................251
ASSEMBLY...........................251
SHIFT MECHANISM
DESCRIPTION........................252OPERATION..........................252
SOLENOID
DESCRIPTION........................252
OPERATION..........................252
SPEED SENSOR
DESCRIPTION........................253
OPERATION..........................253
THROTTLE VALVE CABLE
DESCRIPTION........................253
ADJUSTMENTS - THROTTLE VALVE CABLE . 254
TORQUE CONVERTER
DESCRIPTION........................255
OPERATION..........................259
REMOVAL............................260
INSTALLATION........................260
TORQUE CONVERTER DRAINBACK VALVE
DESCRIPTION........................261
OPERATION..........................261
STANDARD PROCEDURE - TORQUE
CONVERTER DRAINBACK VALVE........261
TOW/HAUL OVERDRIVE SWITCH
DESCRIPTION........................261
OPERATION..........................262
DIAGNOSIS AND TESTING - OVERDRIVE
ELECTRICAL CONTROLS..............262
REMOVAL............................262
INSTALLATION........................262
TRANSMISSION RANGE SENSOR
DESCRIPTION........................263
OPERATION..........................263
DIAGNOSIS AND TESTING - TRANSMISSION
RANGE SENSOR (TRS)................264
REMOVAL............................265
INSTALLATION........................266
TRANSMISSION TEMPERATURE SENSOR
DESCRIPTION........................267
OPERATION..........................267
VALVE BODY
DESCRIPTION........................267
OPERATION..........................272
REMOVAL............................286
DISASSEMBLY........................287
CLEANING...........................298
INSPECTION.........................298
ASSEMBLY...........................299
INSTALLATION........................309
ADJUSTMENTS - VALVE BODY...........310
DRAUTOMATIC TRANSMISSION - 48RE 21 - 131

AUTOMATIC TRANSMISSION -
48RE
DESCRIPTION
The 48RE (Fig. 1) is a four speed fully automatic
transmissions 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 - 132 AUTOMATIC TRANSMISSION - 48REDR

IDENTIFICATION
Transmission identification numbers are stamped
on the left side of the case just above the oil pan gas-
ket surface (Fig. 2). Refer to this information when
ordering replacement parts.
GEAR RATIOS
The 48RE gear ratios are:
1st.................................2.45:1
2nd................................1.45:1
3rd................................1.00:1
4th.................................0.69:1
Rev.................................2.20:1
OPERATION
The application of each driving or holding compo-
nent is controlled by the valve body based upon the
manual lever position, throttle pressure, and gover-
nor pressure. The governor pressure is a variable
pressure input to the valve body and is one of the
signals that a shift is necessary. First through fourth
gear are obtained by selectively applying and releas-
ing the different clutches and bands. Engine power is
thereby routed to the various planetary gear assem-
blies which combine with the overrunning clutch
assemblies to generate the different gear ratios. The
torque converter clutch is hydraulically applied and
is released when fluid is vented from the hydraulic
circuit by the torque converter control (TCC) solenoid
on the valve body. The torque converter clutch is con-
trolled by the Powertrain Control Module (PCM). The
torque converter clutch engages in fourth gear, and
in third gear under various conditions, such as when
the O/D switch is OFF, when the vehicle is cruising
on a level surface after the vehicle has warmed up.
The torque converter clutch can also be engaged in
the MANUAL SECOND gear position if high trans-
mission temperatures are sensed by the PCM. The
torque converter clutch will disengage momentarily
when an increase in engine load is sensed by the
PCM, such as when the vehicle begins to go uphill or
the throttle pressure is increased. The torque con-
verter clutch feature increases fuel economy and
reduces the transmission fluid temperature.
Since the overdrive clutch is applied in fourth gear
only and the direct clutch is applied in all ranges
except fourth gear, the transmission operation for
park, neutral, and first through third gear will be
described first. Once these powerflows are described,
the third to fourth shift sequence will be described.
1 - TORQUE CONVERTER 10 - OVERDRIVE CLUTCH
2 - INPUT SHAFT 11 - DIRECT CLUTCH
3 - OIL PUMP 12 - PLANETARY GEAR
4 - FRONT BAND 13 - INTERMEDIATE SHAFT
5 - FRONT CLUTCH 14 - OVERDRIVE OVERRUNNING CLUTCH
6 - REAR CLUTCH 15 - DIRECT CLUTCH SPRING
7 - PLANETARIES 16 - OVERDRIVE PISTON RETAINER
8 - REAR BAND 17 - OIL PAN
9 - OVERRUNNING CLUTCH 18 - VALVE BODY
Fig. 2 Transmission Part Number And Serial
Number Location
1 - PART NUMBER
2 - BUILD DATE
3 - SERIAL NUMBER
21 - 134 AUTOMATIC TRANSMISSION - 48REDR
AUTOMATIC TRANSMISSION - 48RE (Continued)