1998 DODGE RAM 1500 Driver seat

(9) Mark annulus gear and output shaft for assem-
bly alignment reference (Fig. 144). Use punch or
scriber to mark gear and shaft.
(10) Remove snap-ring that secures annulus gear
on output shaft (Fig. 145). Use two screwdrivers to
unseat and work snap-ring out of groove as shown.
(11) Remove annulus gear from output shaft (Fig.
146). Use rawhide or plastic mallet to tap gear off
shaft.
GEAR CASE AND PARK LOCK
(1) Remove locating ring from gear case.
(2) Remove park pawl shaft retaining bolt and
remove shaft, pawl and spring.
(3) Remove reaction plug snap-ring and remove
reaction plug.
(4) Remove output shaft seal.
CLEANING
Clean the geartrain and case components with sol-
vent. Dry all parts except the bearings with com-
pressed air. Allow bearings to air dry.
Do not use shop towels for wiping parts dry unless
the towels are made from a lint-free material. A suf-
ficient quantity of lint (from shop towels, cloths, rags,
etc.) could plug the transmission filter and fluid pas-
sages.
Discard the old case gasket and seals. Do not
attempt to salvage these parts. They are not reus-
able. Replace any of the overdrive unit snap-rings if
distorted or damaged.
Minor nicks or scratches on components can be
smoothed with crocus cloth. However, do not attempt
to reduce severe scoring on any components with
abrasive materials. Replace severely scored compo-
nents; do not try to salvage them.
INSPECTION
Check condition of the park lock components and
the overdrive case.
Check the bushings in the overdrive case. Replace
the bushings if severely scored or worn. Also replace
the case seal if loose, distorted, or damaged.
Examine the overdrive and direct clutch discs and
plates. Replace the discs if the facing is worn,
severely scored, or burned and flaking off. Replace
the clutch plates if worn, heavily scored, or cracked.
Fig. 144 Marking Annulus Gear And Output Shaft
For Assembly Alignment
1 - OUTPUT SHAFT
2 - HAMMER
3 - PUNCH
Fig. 145 Annulus Gear Snap-Ring Removal
1 - OUTPUT SHAFT
2 - ANNULUS GEAR
3 - SNAP-RING
Fig. 146 Annulus Gear Removal
1 - OUTPUT SHAFT
2 - ANNULUS GEAR
DRAUTOMATIC TRANSMISSION - 48RE 21 - 225
OVERDRIVE UNIT (Continued)

(7) Install overdrive gear case on geartrain (Fig.
166).
(8) Expand front bearing locating ring with snap-
ring pliers (Fig. 167). Then slide case downward until
locating ring locks in bearing groove and release
snap-ring.
(9) Install locating ring access cover and gasket in
overdrive unit case (Fig. 168).
OVERDRIVE CLUTCH
NOTE: The overdrive clutch in a 48RE transmission
uses 5 or 6 clutch discs depending on the applica-
tion.(1) Install overdrive clutch reaction ring first.
Reaction ring is flat with notched ends (Fig. 169).
(2) For 5 disc overdrive clutch versions, install
wave spring on top of reaction ring (Fig. 170). Reac-
tion ring and wave ring both fit in same ring groove.
Use screwdriver to seat each ring securely in groove.
Also ensure that the ends of the two rings are offset
from each other.
(3) Assemble overdrive clutch pack.
(4) Install overdrive clutch reaction plate first.
Fig. 166 Overdrive Gear Case Installation
1 - GEARTRAIN ASSEMBLY
2 - GEAR CASE
Fig. 167 Seating Locating Ring In Rear Bearing
1 - EXPAND BEARING LOCATING RING WITH SNAP-RING
PLIERS
2 - ACCESS HOLE
Fig. 168 Locating Ring Access Cover And Gasket
Installation
1 - TORX SCREWDRIVER (T25)
2 - ACCESS COVER SCREWS
Fig. 169 Overdrive Clutch Reaction Ring Installation
1 - REACTION RING
2 - CLUTCH HUB
Fig. 170 Overdrive Clutch Wave Spring Installation -
5 Disc Clutch Only
1 - WAVE SPRING
21 - 232 AUTOMATIC TRANSMISSION - 48REDR
OVERDRIVE UNIT (Continued)

(10) Install the spacer ring and wave spring into
the retainer. Be sure spring is completely seated in
retainer groove.
(11) Install pressure plate (Fig. 214). Ridged side
of plate faces downward (toward piston) and flat side
toward clutch pack.
(12) Install first clutch disc in retainer on top of
pressure plate. Then install a clutch plate followed
by a clutch disc until entire clutch pack is installed
(4 discs and 3 plates are required) (Fig. 214).
(13) Install the reaction plate.
(14) Install selective snap-ring. Be sure snap-ring
is fully seated in retainer groove.
(15) Using a suitable gauge bar and dial indicator,
measure clutch pack clearance (Fig. 216).
(a) Position gauge bar across the clutch drum
with the dial indicator pointer on the pressure
plate (Fig. 216).
(b) Using two small screw drivers, lift the pres-
sure plate and release it.
(c) Zero the dial indicator.
(d) Lift the pressure plate until it contacts the
snap-ring and record the dial indicator reading.
Clearance should be 0.635 - 0.914 mm (0.025 -
0.036 in.). If clearance is incorrect, steel plates, discs,
selective snap ring and pressure plates may have to
be changed.
The selective snap ring thicknesses are:²0.107 - 0.109 in.
²0.098 - 0.100 in.
²0.095 - 0.097 in.
²0.083 - 0.085 in.
²0.076 - 0.078 in.
²0.071 - 0.073 in.
²0.060 - 0.062 in.
(16) Coat rear clutch thrust washer with petro-
leum jelly and install washer over input shaft and
into clutch retainer (Fig. 217). Use enough petroleum
jelly to hold washer in place.
(17) Set rear clutch aside for installation during
final assembly.
Fig. 215 Pressing Input Shaft Into Rear Clutch
Retainer
1 - INPUT SHAFT
2 - REAR CLUTCH RETAINER
3 - PRESS RAM
Fig. 216 Checking Rear Clutch Pack Clearance
1 - DIAL INDICATOR
2 - PRESSURE PLATE
3 - SNAP-RING
4-STAND
5 - REAR CLUTCH
6 - GAUGE BAR
Fig. 217 Installing Rear Clutch Thrust Washer
1 - REAR CLUTCH RETAINER
2 - REAR CLUTCH THRUST WASHER
21 - 250 AUTOMATIC TRANSMISSION - 48REDR
REAR CLUTCH (Continued)

INSTALLATION
(1) Place TRS selector plate in the PARK position.
(2) Position the transmission solenoid/TRS assem-
bly onto the valve body. Be sure that both alignment
dowels are fully seated in the valve body and that
the TRS switch contacts are properly positioned in
the selector plate
(3) Install the screws to hold the transmission
solenoid/TRS assembly onto the valve body.
(4) Tighten the solenoid assembly screws adjacent
to the arrows cast into the bottom of the valve body
first. Tighten the screws to 5.7 N´m (50 in.lbs.).
(5) Tighten the remainder of the solenoid assembly
screws to 5.7 N´m (50 in.lbs.).
(6) Install the valve body into the transmission.
TRANSMISSION
TEMPERATURE SENSOR
DESCRIPTION
The transmission temperature sensor is a ther-
mistor that is integral to the Transmission Range
Sensor (TRS).
OPERATION
The transmission temperature sensor is used by
the TCM to sense the temperature of the fluid in the
sump. Since fluid temperature can affect transmis-
sion shift quality and convertor lock up, the TCM
requires this information to determine which shift
schedule to operate in.
Calculated Temperature
A failure in the temperature sensor or circuit will
result in calculated temperature being substituted for
actual temperature. Calculated temperature is a pre-
dicted fluid temperature which is calculated from a
combination of inputs:
²Battery (ambient) temperature
²Engine coolant temperature
²In-gear run time since start-up
VALVE BODY
DESCRIPTION
The valve body consists of a cast aluminum valve
body, a separator plate, and a transfer plate. The
valve body contains valves and check balls that con-
trol fluid delivery to the torque converter clutch,
bands, and frictional clutches. The valve body con-
tains the following components (Fig. 129) and (Fig.
130):
²Solenoid switch valve
²Manual valve
²Low/reverse switch valve
²5 Accumulators
²7 check balls
OPERATION
NOTE: Refer to the Hydraulic Schematics for a
visual aid in determining valve location, operation
and design.
SOLENOID SWITCH VALVE
The Solenoid Switch Valve (SSV) controls the direc-
tion of the transmission fluid when the L/R-TCC sole-
noid is energized.
When shifting into 1st gear, a special hydraulic
sequence is performed to ensure SSV movement into
the downshifted position. The L/R pressure switch is
monitored to confirm SSV movement. If the move-
ment is not confirmed (the L/R pressure switch does
not close), 2nd gear is substituted for 1st. A DTC will
be set after three unsuccessful attempts are made to
get into 1st gear in one given key start.
MANUAL VALVE
The manual valve is a relay valve. The purpose of
the manual valve is to direct fluid to the correct cir-
cuit needed for a specific gear or driving range. The
manual valve, as the name implies, is manually oper-
ated by the driver with a lever located on the top of
the valve body. The valve is connected mechanically
by a cable to the gearshift mechanism. The valve is
held in each of its positions by a roller detent spring
(Fig. 131) that engages the ªroostercombº of the TRS
selector plate.
21 - 408 AUTOMATIC TRANSMISSION - 45RFE/545RFEDR
TRANSMISSION SOLENOID/TRS ASSEMBLY (Continued)

INSTRUMENT PANEL
TABLE OF CONTENTS
page page
CLUSTER BEZEL
REMOVAL.............................49
INSTALLATION.........................49
ASH RECEIVER
REMOVAL.............................50
INSTALLATION.........................51
CUP HOLDER
REMOVAL.............................51
INSTALLATION.........................51
GLOVE BOX
REMOVAL.............................52
INSTALLATION.........................52
GLOVE BOX LATCH
REMOVAL.............................52
INSTALLATION.........................52
INSTRUMENT PANEL ASSEMBLY
REMOVAL.............................52
INSTALLATION.........................55
INSTRUMENT PANEL HEADLAMP SWITCH
BEZEL
REMOVAL.............................56
INSTALLATION.........................56INSTRUMENT PANEL CENTER BEZEL
REMOVAL.............................57
INSTALLATION.........................57
INSTRUMENT PANEL DRIVER SIDE BEZEL
REMOVAL.............................58
INSTALLATION.........................58
INSTRUMENT PANEL TOP COVER
REMOVAL.............................58
INSTALLATION.........................59
INSTRUMENT PANEL LOWER SURROUND
REMOVAL.............................59
INSTALLATION.........................59
STEERING COLUMN OPENING COVER
REMOVAL.............................60
INSTALLATION.........................60
STEERING COLUMN OPENING SUPPORT
BRACKET
REMOVAL.............................60
INSTALLATION.........................60
STORAGE BIN
REMOVAL.............................61
INSTALLATION.........................61
CLUSTER BEZEL
REMOVAL
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE AIRBAG SYSTEM BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, SEAT BELT TENSIONER, OR INSTRU-
MENT PANEL COMPONENT DIAGNOSIS OR SER-
VICE. DISCONNECT AND ISOLATE THE BATTERY
NEGATIVE (GROUND) CABLE, THEN WAIT TWO
MINUTES FOR THE AIRBAG SYSTEM CAPACITOR
TO DISCHARGE BEFORE PERFORMING FURTHER
DIAGNOSIS OR SERVICE. THIS IS THE ONLY SURE
WAY TO DISABLE THE AIRBAG SYSTEM. FAILURE
TO TAKE THE PROPER PRECAUTIONS COULD
RESULT IN ACCIDENTAL AIRBAG DEPLOYMENT
AND POSSIBLE PERSONAL INJURY.
(1) Remove the headlamp switch bezel. (Refer to
23 - BODY/INSTRUMENT PANEL/INSTRUMENT
PANEL SWITCH BEZEL - REMOVAL)
(2) Remove the center bezel. (Refer to 23 - BODY/
INSTRUMENT PANEL/INSTRUMENT PANEL
CENTER BEZEL - REMOVAL)(3) Remove the two top screws. (Fig. 1)
(4) Using a trim stick C-4755 or equivalent, sepa-
rate the two lower clips.
(5) Disengage the two top attachment bosses and
remove the bezel.
INSTALLATION
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE AIRBAG SYSTEM BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, SEAT BELT TENSIONER, OR INSTRU-
MENT PANEL COMPONENT DIAGNOSIS OR SER-
VICE. DISCONNECT AND ISOLATE THE BATTERY
NEGATIVE (GROUND) CABLE, THEN WAIT TWO
MINUTES FOR THE AIRBAG SYSTEM CAPACITOR
TO DISCHARGE BEFORE PERFORMING FURTHER
DIAGNOSIS OR SERVICE. THIS IS THE ONLY SURE
WAY TO DISABLE THE AIRBAG SYSTEM. FAILURE
TO TAKE THE PROPER PRECAUTIONS COULD
RESULT IN ACCIDENTAL AIRBAG DEPLOYMENT
AND POSSIBLE PERSONAL INJURY.
(1) Position the cluster bezel over the cluster and
seat the outer bosses over the posts on the left and
right sides.
DRINSTRUMENT PANEL 23 - 49

(23) Remove the two right side mounting bolts on
the a-pillar and one right mounting bolt on the cowl
side panel. (Fig. 14)
(24) Remove the four top instrument panel screws.
(Fig. 15)
(25) Remove the two top instrument panel bolts
and remove the instrument panel.INSTALLATION
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE AIRBAG SYSTEM BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, SEAT BELT TENSIONER, OR INSTRU-
MENT PANEL COMPONENT DIAGNOSIS OR SER-
VICE. DISCONNECT AND ISOLATE THE BATTERY
NEGATIVE (GROUND) CABLE, THEN WAIT TWO
MINUTES FOR THE AIRBAG SYSTEM CAPACITOR
TO DISCHARGE BEFORE PERFORMING FURTHER
DIAGNOSIS OR SERVICE. THIS IS THE ONLY SURE
WAY TO DISABLE THE AIRBAG SYSTEM. FAILURE
TO TAKE THE PROPER PRECAUTIONS COULD
RESULT IN ACCIDENTAL AIRBAG DEPLOYMENT
AND POSSIBLE PERSONAL INJURY.
(1) Position the instrument panel assembly in
vehicle.
(2) Route the park brake release rod through the
instrument panel. (Fig. 16)
(3) Install the instrument panel onto the left side
guide pin and the right side guide hook.
(4) Install the left side mounting bolts and tighten
to 12 N´m (9 ft. lbs.).
(5) Install the instrument panel drivers side bezel.
(Refer to 23 - BODY/INSTRUMENT PANEL/IN-
STRUMENT PANEL DRIVERS SIDE BEZEL -
INSTALLATION)
(6) Install the left cowl trim panel. (Refer to 23 -
BODY/INTERIOR/COWL TRIM - INSTALLATION)
(7) Connect the headliner harness electrical con-
nector at the a-pillar.
Fig. 14 PASSENGER SIDE MOUNTING
1 - INSTRUMENT PANEL
2 - RIGHT SIDE MOUNTING HOOK
3 - A-PILLAR
4 - END CAP
5 - MOUNTING BOLTS (3)
Fig. 15 UPPER COWL PANEL BOLTS
1 - COWL PANEL
2 - FORWARD MOST SCREWS (4)
3 - BOLT INSERTS (4)
4 - REARWARD BOLTS (2)
5 - INSTRUMENT PANEL
Fig. 16 BRAKE RELEASE ROD
1 - PARK BRAKE RELEASE HANDLE
2 - PARK BRAKE RELEASE ROD
3 - INSTRUMENT PANEL
DRINSTRUMENT PANEL 23 - 55
INSTRUMENT PANEL ASSEMBLY (Continued)

(8) Install the left a-pillar trim. (Refer to 23 -
BODY/INTERIOR/A-PILLAR TRIM - INSTALLA-
TION)
(9) Position the left end cap and seat the attach-
ment clips fully.
(10) Install the right side mounting bolts on the
a-pillar and one right mounting bolt on the cowl side
panel and tighten to 12 N´m (9 ft. lbs.).
(11) Install the right a-pillar trim panel. (Refer to
23 - BODY/INTERIOR/A-PILLAR TRIM - INSTAL-
LATION)
(12) Position the right end cap and seat the
attachment clips fully.
(13) Install the one HVAC mounting screw.
(14) Connect the radio antenna.
(15) Connect the two electrical connectors at the
right cowl panel.
(16) Install the right cowl trim cover. (Refer to 23 -
BODY/INTERIOR/COWL TRIM - INSTALLATION)
(17) Connect the air bag control module electrical
connector.
(18) Install the center bracket bolts and tighten to
12 N´m (9 ft. lbs.).
(19) Install the floor console, if equipped. (Refer to
23 - BODY/INTERIOR/FLOOR CONSOLE - INSTAL-
LATION)
(20) Install the air bag control module cover, if
equipped.
(21) Connect the park brake release handle actua-
tor rod.
(22) Install the hood release handle and tighten
the screws.
(23) Install the two bolts at the column support
bracket and tighten to 14 N´m (10 ft. lbs.).
(24) Install the steering column. (Refer to 19 -
STEERING/COLUMN - INSTALLATION)
(25) Connect the wire harness electrical connectors
above the brake pedal.
(26) Install the two top instrument panel bolts and
tighten to 12 N´m (9 ft. lbs.).
(27) Install the four top instrument panel screws.
(28) Install the instrument panel top cover. (Refer
to 23 - BODY/INSTRUMENT PANEL/INSTRUMENT
PANEL TOP COVER - INSTALLATION)
INSTRUMENT PANEL
HEADLAMP SWITCH BEZEL
REMOVAL
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE AIRBAG SYSTEM BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, SEAT BELT TENSIONER, OR INSTRU-
MENT PANEL COMPONENT DIAGNOSIS OR SER-VICE. DISCONNECT AND ISOLATE THE BATTERY
NEGATIVE (GROUND) CABLE, THEN WAIT TWO
MINUTES FOR THE AIRBAG SYSTEM CAPACITOR
TO DISCHARGE BEFORE PERFORMING FURTHER
DIAGNOSIS OR SERVICE. THIS IS THE ONLY SURE
WAY TO DISABLE THE AIRBAG SYSTEM. FAILURE
TO TAKE THE PROPER PRECAUTIONS COULD
RESULT IN ACCIDENTAL AIRBAG DEPLOYMENT
AND POSSIBLE PERSONAL INJURY.
(1) Using a trim stick C-4755 or equivalent,
release the top clips on the steering column opening
cover and the lower drivers side bezel.
(2) Using a trim stick C-4755 or equivalent,
release the switch bezel. (Fig. 17)
(3) Disconnect the electrical connector and remove
the bezel.
INSTALLATION
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE AIRBAG SYSTEM BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, SEAT BELT TENSIONER, OR INSTRU-
MENT PANEL COMPONENT DIAGNOSIS OR SER-
VICE. DISCONNECT AND ISOLATE THE BATTERY
NEGATIVE (GROUND) CABLE, THEN WAIT TWO
MINUTES FOR THE AIRBAG SYSTEM CAPACITOR
TO DISCHARGE BEFORE PERFORMING FURTHER
DIAGNOSIS OR SERVICE. THIS IS THE ONLY SURE
WAY TO DISABLE THE AIRBAG SYSTEM. FAILURE
TO TAKE THE PROPER PRECAUTIONS COULD
RESULT IN ACCIDENTAL AIRBAG DEPLOYMENT
AND POSSIBLE PERSONAL INJURY.
(1) Connect the electrical connector.
Fig. 17 HEADLIGHT SWITCH BEZEL
1 - SWITCH BEZEL
2 - INSTRUMENT PANEL
3 - ELECTRICAL CONNECTOR
4 - HEADLIGHT SWITCH
23 - 56 INSTRUMENT PANELDR
INSTRUMENT PANEL ASSEMBLY (Continued)

(2) Position the switch bezel and seat the attach-
ment clips fully.
(3) Seat the clips on the steering column opening
cover and the lower drivers side bezel fully.
INSTRUMENT PANEL CENTER
BEZEL
REMOVAL
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE AIRBAG SYSTEM BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, SEAT BELT TENSIONER, OR INSTRU-
MENT PANEL COMPONENT DIAGNOSIS OR SER-
VICE. DISCONNECT AND ISOLATE THE BATTERY
NEGATIVE (GROUND) CABLE, THEN WAIT TWO
MINUTES FOR THE AIRBAG SYSTEM CAPACITOR
TO DISCHARGE BEFORE PERFORMING FURTHER
DIAGNOSIS OR SERVICE. THIS IS THE ONLY SURE
WAY TO DISABLE THE AIRBAG SYSTEM. FAILURE
TO TAKE THE PROPER PRECAUTIONS COULD
RESULT IN ACCIDENTAL AIRBAG DEPLOYMENT
AND POSSIBLE PERSONAL INJURY.
CAUTION: When removing and installing the center
bezel, use tape or other suitable material to protect
the cupholder and ash receiver from damage.
(1) Disconnect and isolate the negative battery
cable.
(2) Remove the steering column opening cover.
(Refer to 23 - BODY/INSTRUMENT PANEL/STEER-
ING COLUMN OPENING COVER - REMOVAL)
(3) Open the ashtray and cup holder.
(4) Remove the one center bezel retaining screw
(Fig. 18).
CAUTION: Extreme care must be taken not to
scratch the ashtray door while removing the instru-
ment panel center bezel. Apply masking tape to the
ashtray door if the center bezel is not being com-
pletely removed from the instrument panel.
(5) Using a trim stick C-4755 or equivalent, gently
pry the center bezel free from the instrument panel.
(6) Working behind the center bezel, disconnect all
electrical connectors and remove the bezel.
INSTALLATION
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE AIRBAG SYSTEM BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, SEAT BELT TENSIONER, OR INSTRU-
MENT PANEL COMPONENT DIAGNOSIS OR SER-
VICE. DISCONNECT AND ISOLATE THE BATTERY
NEGATIVE (GROUND) CABLE, THEN WAIT TWO
MINUTES FOR THE AIRBAG SYSTEM CAPACITOR
TO DISCHARGE BEFORE PERFORMING FURTHER
DIAGNOSIS OR SERVICE. THIS IS THE ONLY SURE
WAY TO DISABLE THE AIRBAG SYSTEM. FAILURE
TO TAKE THE PROPER PRECAUTIONS COULD
RESULT IN ACCIDENTAL AIRBAG DEPLOYMENT
AND POSSIBLE PERSONAL INJURY.
CAUTION: When removing and installing the center
bezel, use tape or other suitable material to protect
the cupholder and ash receiver from damage.
(1) Working behind the center bezel, connect all
electrical connectors.
(2) Gently install the center bezel on the instru-
ment panel by pushing straight in and seat the
attachment clips fully.
(3) Install the one center bezel screw.
(4) Install the steering column opening cover.
(Refer to 23 - BODY/INSTRUMENT PANEL/STEER-
ING COLUMN OPENING COVER - INSTALLA-
TION)
(5) Connect the negative battery cable.
Fig. 18 CENTER BEZEL
1 - INSTRUMENT PANEL
2 - CENTER BEZEL
3 - SCREW
DRINSTRUMENT PANEL 23 - 57
INSTRUMENT PANEL HEADLAMP SWITCH BEZEL (Continued)