1998 DODGE RAM 1500 Drive shaft

(a) Start park rod into park pawl. If rod will not
slide past park pawl, pawl is engaged in park gear.
Rotate overdrive output shaft with suitable size 12
point socket; this will free pawl and allow rod to
engage.
(b) Align and seat valve body on case. Be sure
manual lever shaft and overdrive connector are
fully seated in case.
(c) Install and start all valve body attaching
bolts by hand. Then tighten bolts evenly, in a diag-
onal pattern to 12 N´m (105 in. lbs.) torque.Do
not overtighten valve body bolts. This could
result in distortion and cross leakage after
installation..
(5) Install new filter on valve body. Tighten filter
screws to 4 N´m (35 in. lbs.).
CAUTION: If the condition of the transmission
before the overhaul procedure caused excessive
metallic or fiber contamination in the fluid, replace
the torque converter and reverse flush the cooler(s)
and cooler lines. Fluid contamination and transmis-
sion failure can result if not done.(6) Move the transmission manual shaft lever to
the manual LOW position.
(7) Install the TRS mounting bracket into the
transmission case. Using Adapter 8581 (Fig. 60),
tighten the mounting bracket to 34 N´m (300 in.lbs.).
(8) Install the TRS (Fig. 61) into the mounting
bracket with the wiring connector facing the front of
the transmission.
Fig. 58 Accumulator Piston And Springs
1 - ACCUMULATOR PISTON
2 - OUTER SPRING
3 - INNER SPRING
Fig. 59 Manual Lever Shaft Seal
1 - 15/1688SOCKET
2 - SEAL
Fig. 60 Tighten the TRS Mounting Bracket
1 - SOLENOID CASE CONNECTOR
2 - TRS MOUNTING BRACKET
3 - ADAPTER 8581
Fig. 61 Remove Transmission Range Sensor
1 - SOLENOID CASE CONNECTOR
2 - TRS MOUNTING BRACKET
3 - TRANSMISSION RANGE SENSOR
DRAUTOMATIC TRANSMISSION - 48RE 21 - 173
AUTOMATIC TRANSMISSION - 48RE (Continued)

(9) Install the two screws to hold the TRS to the
mounting bracket. Tighten the screws to 5 N´m (45
in.lbs.).
(10) Verify proper sensor operation (Fig. 62).
(11) Move the transmission manual shaft lever to
the PARK position.
(12) Install torque converter. Use C-clamp or metal
strap to hold converter in place for installation.
BAND ADJUSTMENT AND FINAL
(1) Adjust front and rear bands as follows:
(a) Loosen locknut on each band adjusting screw
4-5 turns.
(b) Tighten both adjusting screws to 8 N´m (72
in. lbs.).
(c) Back off front band adjusting screw 1-3/4
turns.
(d) Back off rear band adjusting screw 3 turns.
(e) Hold each adjusting screw in position and
tighten locknut to 34 N´m (25 ft. lbs.) torque.
(2) Install magnet in oil pan. Magnet seats on
small protrusion at corner of pan.
(3) Position new oil pan gasket on case and install
oil pan. Tighten pan bolts to 13.6 N´m (125 in. lbs.).
(4) Install throttle valve and shift selector levers
on valve body manual lever shaft.
(5) Apply small quantity of dielectric grease to ter-
minal pins of solenoid case connector and neutral
switch.
(6) Fill transmission with recommended fluid.
INSTALLATION
(1) Check torque converter hub inner and outer
diameters and hub drive notches for sharp edgesburrs, scratches, or nicks. Polish the hub and notches
with 320/400 grit paper and crocus cloth if necessary.
The hub must be smooth to avoid damaging pump
seal at installation.
(2) Lubricate pocket in the rear oil pump seal lip
with transmission fluid.
(3) Lubricate converter pilot hub of the crankshaft
with a light coating of MopartHigh Temp Grease.
(4) Align and install converter in oil pump.
(5) Carefully insert converter in oil pump. Then
rotate converter back and forth until fully seated in
pump gears.
(6) Check converter seating with steel scale and
straightedge (Fig. 63). Surface of converter lugs
should be 19mm (0.75 in.) to rear of straightedge
when converter is fully seated.
(7) Temporarily secure converter with C-clamp.
(8) Position transmission on jack and secure it
with chains.
(9) Check condition of converter driveplate.
Replace the plate if cracked, distorted or damaged.
Also be sure transmission dowel pins are seated
in engine block and protrude far enough to
hold transmission in alignment.
(10) Raise transmission and align converter with
drive plate and converter housing with engine block.
(11) Move transmission forward. Then raise, lower
or tilt transmission to align converter housing with
engine block dowels.
(12) Carefully work transmission forward and over
engine block dowels until converter hub is seated in
crankshaft.
Fig. 62 Transmission Range Sensor Operation
1 - NEUTRAL CONTACT
2 - MANUAL LEVER AND SENSOR PLUNGER IN REVERSE
POSITION
3 - PARK CONTACT
4 - TRANSMISSION RANGE SENSOR
Fig. 63 Checking Converter Seating - Typical
1 - SCALE
2 - STRAIGHTEDGE
21 - 174 AUTOMATIC TRANSMISSION - 48REDR
AUTOMATIC TRANSMISSION - 48RE (Continued)

(13) Install bolts attaching converter housing to
engine.
(14) Install rear support.
(15) Install the rear transmission crossmember.
(16) Lower transmission onto crossmember and
install bolts attaching transmission mount to cross-
member.
(17) Remove engine support fixture.
(18) Install the transfer case, if equipped.
(19) Install crankshaft position sensor. (Refer to 14
- FUEL SYSTEM/FUEL INJECTION/CRANKSHAFT
POSITION SENSOR - INSTALLATION)
(20) Connect gearshift cable (Fig. 64) and throttle
cable to transmission.
(21) Connect wires to the transmission range sen-
sor and transmission solenoid connector. Be sure the
transmission harnesses are properly routed.
CAUTION: It is essential that correct length bolts be
used to attach the converter to the driveplate. Bolts
that are too long will damage the clutch surface
inside the converter.(22) Install torque converter-to-driveplate bolts.
(23) Install converter housing access cover.
(24) Install starter motor and cooler line bracket.
(Refer to 8 - ELECTRICAL/STARTING/STARTER
MOTOR - INSTALLATION)
(25) Connect cooler lines (Fig. 65) to transmission.
(26) Install transmission fill tube. Install new seal
on tube before installation.
(27) Install any exhaust components previously
removed.
(28) Align and connect propeller shaft. (Refer to 3 -
DIFFERENTIAL & DRIVELINE/PROPELLER
SHAFT/PROPELLER SHAFT - INSTALLATION)
(29) Adjust gearshift cable and throttle valve
cable, if necessary.
(30) Install the transfer case skid plate, if
equipped.
(31) Lower vehicle.
(32) Fill transmission with MopartATF +4, Auto-
matic Transmission fluid.
Fig. 64 Gearshift Cable At Transmission
1 - GEARSHIFT CABLE
2 - TRANSMISSION MANUAL LEVER
3 - CABLE SUPPORT BRACKET
Fig. 65 Transmission Cooler Lines
1 - TRANSMISSION
2 - RADIATOR
3 - COOLER LINES
DRAUTOMATIC TRANSMISSION - 48RE 21 - 175
AUTOMATIC TRANSMISSION - 48RE (Continued)

SPECIFICATIONS
TRANSMISSION
GENERAL
Component Metric Inch
Planetary end play 0.150-1.22
mm0.006-0.048
in.
Input shaft end play 0.86-2.13
mm0.034-0.084
in.
Clutch pack clearance/
Front.2.5-4.09
mm0.098-0.161
in.
Clutch pack clearance/
Rear.0.635-0.914
mm0.025-0.036
in.
Front clutch 5 discs
Rear clutch 4 discs
Overdrive clutch 5(STD) OR 6(Diesel HO)
discs
Direct clutch 23 Single Sided discs
Band adjustment from
72 in. lbs.
Front band Back off 1 3/4 turns
Rear band Back off 3 turns
Recommended fluid MoparTAT F + 4GEAR RATIOS
1ST GEAR 2.45:1
2ND GEAR 1.45:1
3RD GEAR 1.0:1
4TH GEAR 0.69:1
REVERSE 2.20:1
THRUST WASHER/SPACER/SNAP-RING DIMENSIONS
Component Metric Inch
Front clutch thrust washer (reaction shaft support hub) 1.55 mm 0.061 in.
2.15 mm 0.084 in.
2.59 mm 0.102 in.
Rear clutch thrust washer (clutch retainer) 1.55 mm 0.061 in.
Intermediate shaft thrust plate (shaft hub pilot) 1.5-1.6 mm 0.060-0.063 in.
Output shaft thrust washer (rear clutch hub) 1.3-1.4 mm 0.052-0.054 in.
1.75-1.8 mm 0.068-0.070 in.
2.1-2.2 mm 0.083-0.085 in.
Rear clutch pack snap-ring 1.5-1.6 mm 0.060-0.062 in.
1.9-1.95 mm 0.074-0.076 in.
Planetary geartrain snap-ring (at front of output shaft) 1.4-1.5 mm 0.055-0.059 in.
1.6-1.7 mm 0.062-0.066 in.
Overdrive piston thrust plate Thrust plate and
spacer are select fit.
Refer to size charts
and selection
procedures in
Overdrive Unit D&A
procedures Intermediate shaft spacer
DRAUTOMATIC TRANSMISSION - 48RE 21 - 189
AUTOMATIC TRANSMISSION - 48RE (Continued)

PRESSURE TEST
Overdrive clutch Fourth gear only Pressure should be 524-565 kPa (76-82 psi) with
closed throttle and increase to 965 kPa (140 psi) at 1/2
to 3/4 throttle.
Line pressure (at
accumulator)Closed throttle 372-414 kPa (54-60 psi).
Front servo Third or Fourth gear only No more than 21 kPa (3 psi) lower than line pressure.
Rear servo 1 range No more than 21 kPa (3 psi) lower than line pressure.
R range 1103 kPa (160 psi) at idle, builds to 1862 kPa (270 psi)
at 1600 rpm.
Governor D range closed throttle Pressure should respond smoothly to changes in mph
and return to 0-7 kPa (0-1.5 psi) when stopped with
transmission in D, 1, 2. Pressure above 7 kPa (1.5 psi)
at stand still will prevent transmission from
downshifting.
TORQUE SPECIFICATIONS
DESCRIPTION N´m Ft. Lbs. In. Lbs.
Fitting, cooler line at trans 18 13 -
Bolt, torque convertor 47 35 -
Bolt, clevis bracket to crossmember 47 35 -
Bolt, clevis bracket to rear support 68 50 -
Bolt, driveplate to crankshaft 75 55 -
Plug, front band reaction 17 13 -
Locknut, front band adj. 34 25 -
Bolt, fluid pan 13.6 - 120
Screws, fluid filter 4 - 35
Bolt, oil pump 20 15 -
Bolt, overrunning clutch cam 17 13 -
Bolt, O/D to trans. 34 25 -
Bolt, O/D piston retainer 17 13 -
Plug, pressure test port 14 10 -
Bolt, reaction shaft support 20 15 -
Locknut, rear band 41 30 -
Bolt, valve body to case 12 - 100
Sensor, trans speed 27 20 -
Screw, solenoid wiring connector 4 - 35
Screw, solenoid to transfer plate 4 - 35
Bracket, transmission range sensor mounting 34 25 -
Screw, transmision range sensor to mounting
bracket5-45
21 - 190 AUTOMATIC TRANSMISSION - 48REDR
AUTOMATIC TRANSMISSION - 48RE (Continued)

sure curve is higher than normal to make the
transmission shift at normal speeds and sooner. The
PCM uses a temperature sensor in the transmission
oil sump to determine when low temperature gover-
nor pressure is needed.
NORMAL OPERATION
Normal operation is refined through the increased
computing power of the PCM and through access to
data on engine operating conditions provided by the
PCM that were not available with the previous
stand-alone electronic module. This facilitated the
development of a load adaptive shift strategy - the
ability to alter the shift schedule in response to vehi-
cle load condition. One manifestation of this capabil-
ity is grade9hunting9prevention - the ability of the
transmission logic to delay an upshift on a grade if
the engine does not have sufficient power to main-
tain speed in the higher gear. The 3-2 downshift and
the potential for hunting between gears occurs with a
heavily loaded vehicle or on steep grades. When
hunting occurs, it is very objectionable because shifts
are frequent and accompanied by large changes in
noise and acceleration.
WIDE OPEN THROTTLE OPERATION
In wide-open throttle (WOT) mode, adaptive mem-
ory in the PCM assures that up-shifts occur at the
preprogrammed optimum speed. WOT operation is
determined from the throttle position sensor, which
is also a part of the emission control system. The ini-
tial setting for the WOT upshift is below the opti-
mum engine speed. As WOT shifts are repeated, the
PCM learns the time required to complete the shifts
by comparing the engine speed when the shifts occur
to the optimum speed. After each shift, the PCM
adjusts the shift point until the optimum speed is
reached. The PCM also considers vehicle loading,
grade and engine performance changes due to high
altitude in determining when to make WOT shifts. It
does this by measuring vehicle and engine accelera-
tion and then factoring in the shift time.
TRANSFER CASE LOW RANGE OPERATION
On four-wheel drive vehicles operating in low
range, the engine can accelerate to its peak more
rapidly than in Normal range, resulting in delayed
shifts and undesirable engine9flare.9The low range
governor pressure curve is also higher than normal
to initiate upshifts sooner. The PCM compares elec-
tronic vehicle speed signal used by the speedometer
to the transmission output shaft speed signal to
determine when the transfer case is in low range.REMOVAL
(1) Hoist and support vehicle on safety stands.
(2) Remove transmission fluid pan and filter.
(3) Disengage wire connectors from pressure sen-
sor and solenoid (Fig. 78).
(4) Remove screws holding pressure solenoid
retainer to governor body.
(5) Separate solenoid retainer from governor (Fig.
79).
Fig. 78 Governor Solenoid And Pressure Sensor
1 - PRESSURE SENSOR
2 - PRESSURE SOLENOID
3 - GOVERNOR
Fig. 79 Pressure Solenoid Retainer
1 - PRESSURE SOLENOID RETAINER
2 - GOVERNOR
DRAUTOMATIC TRANSMISSION - 48RE 21 - 199
ELECTRONIC GOVERNOR (Continued)

(10) Place solenoid retainer in position on governor
(Fig. 84).
(11) Install screws to hold pressure solenoid
retainer to governor body.
(12) Engage wire connectors into pressure sensor
and solenoid (Fig. 85).
(13) Install transmission fluid pan and (new) filter.
(14) Lower vehicle and road test to verify repair.
EXTENSION HOUSING SEAL
REMOVAL
(1) Raise vehicle.
(2) Mark propeller shaft and axle yoke for align-
ment reference.
(3) Disconnect and remove propeller shaft.(4) Remove old seal with a screw mounted in a
slide hammer.
INSTALLATION
(1) Place seal in position on overdrive housing.
(2) Drive seal into overdrive housing with Seal
Installer 9037 (Fig. 86).
(3) Carefully guide propeller shaft slip yoke into
housing and onto output shaft splines. Align marks
made at removal and connect propeller shaft to rear
axle pinion yoke.
FLUID AND FILTER
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - EFFECTS OF
INCORRECT FLUID LEVEL
A low fluid level allows the pump to take in air
along with the fluid. Air in the fluid will cause fluid
pressures to be low and develop slower than normal.
If the transmission is overfilled, the gears churn the
fluid into foam. This aerates the fluid and causing
the same conditions occurring with a low level. In
either case, air bubbles cause fluid overheating, oxi-
dation and varnish buildup which interferes with
valve and clutch operation. Foaming also causes fluid
expansion which can result in fluid overflow from the
transmission vent or fill tube. Fluid overflow can eas-
ily be mistaken for a leak if inspection is not careful.
DIAGNOSIS AND TESTING - CAUSES OF
BURNT FLUID
Burnt, discolored fluid is a result of overheating
which has two primary causes.
(1) A result of restricted fluid flow through the
main and/or auxiliary cooler. This condition is usu-
ally the result of a faulty or improperly installed
drainback valve, a damaged main cooler, or severe
restrictions in the coolers and lines caused by debris
or kinked lines.
Fig. 84 Pressure Solenoid Retainer
1 - PRESSURE SOLENOID RETAINER
2 - GOVERNOR
Fig. 85 Governor Solenoid And Pressure Sensor
1 - PRESSURE SENSOR
2 - PRESSURE SOLENOID
3 - GOVERNOR
Fig. 86 Installing Overdrive Housing Yoke Seal
1 - SPECIAL TOOL 9037
2 - SPECIAL TOOL C-4171
DRAUTOMATIC TRANSMISSION - 48RE 21 - 201
ELECTRONIC GOVERNOR (Continued)

(4) Align and install reaction shaft support on
pump body.
(5) Install bolts attaching reaction shaft support to
pump. Tighten bolts to 20 N´m (175 in. lbs.) torque.
(6) Install new pump seal with Installer Tool
C-3860-A (Fig. 114). Use hammer or mallet to tap
seal into place.
(7) Install new o-ring on pump body. Lubricate oil
seal and o-ring with petroleum jelly.
(8) Cover pump assembly to prevent dust entry
and set aside for assembly installation.
OUTPUT SHAFT FRONT
BEARING
REMOVAL
(1) Remove overdrive unit from the vehicle.
(2) Remove overdrive geartrain from housing.
(3) Remove snap-ring holding output shaft front
bearing to overdrive geartrain. (Fig. 115).
(4) Pull bearing from output shaft.
INSTALLATION
(1) Place replacement bearing in position on
geartrain with locating retainer groove toward the
rear.
(2) Push bearing onto shaft until the snap-ring
groove is visible.
(3) Install snap-ring to hold bearing onto output
shaft.
(4) Install overdrive geartrain into housing.
(5) Install overdrive unit in vehicle.
OUTPUT SHAFT REAR
BEARING
REMOVAL
(1) Remove overdrive unit from the vehicle. (Refer
to 21 - TRANSMISSION/AUTOMATIC/OVERDRIVE
- REMOVAL)
(2) Remove overdrive geartrain from housing.
(3) Remove snap-ring holding output shaft rear
bearing into overdrive housing (Fig. 116).
(4) Using a suitable driver inserted through the
rear end of housing, drive bearing from housing.
Fig. 114 Oil Pump Seal
1 - SPECIAL TOOL C-3860-A
2 - PUMP BODY
3 - PUMP SEAL
Fig. 115 Output Shaft Front Bearing
1 - OUTPUT SHAFT FRONT BEARING
2 - SNAP-RING
3 - OUTPUT SHAFT
4 - GROOVE TO REAR
5 - OVERDRIVE GEARTRAIN
Fig. 116 Output Shaft Rear Bearing
1 - OUTPUT SHAFT REAR BEARING
2 - OVERDRIVE HOUSING
3 - SNAP-RING
21 - 216 AUTOMATIC TRANSMISSION - 48REDR
OIL PUMP (Continued)