1998 DODGE RAM 1500 Sensor

SPECIFICATIONS
TRANSMISSION
GENERAL
Component Metric Inch
Output Shaft End Play 0.22-0.55
mm0.009-0.021
in.
Input Shaft End Play 0.46-0.89
mm0.018-0.035
in.
2C Clutch Pack
Clearance0.455-1.335
mm0.018-0.053
in.
4C Clutch Pack
Clearance0.770-1.390
mm0.030-0.055
in.
L/R Clutch Pack
Clearance1.00-1.74
mm0.039-0.069
in.
OD Clutch Pack
Clearance1.103-1.856
mm0.043-0.073
in.
Component Metric Inch
UD Clutch Pack
Clearance0.84-1.54
mm0.033-0.061
in.
Reverse Clutch Pack
Clearance0.81-1.24
mm0.032-0.049
in.
Recommended fluid MoparTAT F + 4
GEAR RATIOS
1ST 3.00:1
2ND 1.67:1
2ND Prime 1.50:1
3RD 1.0:1
4TH 0.75:1
5TH 0.67:1
REVERSE 3.00:1
TORQUE SPECIFICATIONS
DESCRIPTION N´m Ft. Lbs. In. Lbs.
Fitting, cooler line at trans 17.5 - 155
Bolt, torque convertor 31 23 -
Bolt/nut, crossmember 68 50 -
Bolt, driveplate to crankshaft 75 55 -
Bolt, oil pan 11.8 - 105
Screw, primary fluid filter 4.5 - 40
Bolt, oil pump 28.2 - 250
Bolt, oil pump body to cover 4.5 - 40
Screw, plate to oil pump body 4.5 - 40
Bolt, valve body to case 11.8 - 105
Plug, pressure test port 5.1 - 45
Bolt, reaction shaft support 11.8 - 105
Screw, valve body to transfer plate 5.6 - 50
Screw, solenoid module to transfer plate 5.7 - 50
Screw, accumulator cover 8 - 70
Screw, detent spring 4.5 - 40
Bolt, input speed sensor 11.8 - 105
Bolt, output speed sensor 11.8 - 105
Bolt, line pressure sensor 11.8 - 105
Bolt, extension housing 54 40 -
Valve, cooler return filter bypass 4.5 - 40
Screw, manual valve cam retaining 4.5 - 40
Bolt, manual lever 28.2 - 250
21 - 358 AUTOMATIC TRANSMISSION - 45RFE/545RFEDR
AUTOMATIC TRANSMISSION - 45RFE/545RFE (Continued)

imately at the upper COLD hole of the dipstick at
70É F fluid temperature.
NOTE: Engine and Transmission should be at nor-
mal operating temperature before performing this
procedure.
(1) Start engine and apply parking brake.
(2) Shift the transmission into DRIVE for approxi-
mately 2 seconds.
(3) Shift the transmission into REVERSE for
approximately 2 seconds.
(4) Shift the transmission into PARK.
(5) Hook up DRBtscan tool and select transmis-
sion.
(6) Select sensors.
(7) Read the transmission temperature value.
(8) Compare the fluid temperature value with the
chart. (Fig. 66)
(9) Adjust transmission fluid level shown on the
dipstick according to the chart.
NOTE: After adding any fluid to the transmission,
wait a minimum of 2 minutes for the oil to fully
drain from the fill tube into the transmission before
rechecking the fluid level.
(10) Check transmission for leaks.STANDARD PROCEDURE - FLUID AND FILTER
REPLACEMENT
For proper service intervals (Refer to LUBRICA-
TION & MAINTENANCE/MAINTENANCE SCHED-
ULES - DESCRIPTION).
REMOVAL
(1) Hoist and support vehicle on safety stands.
(2) Place a large diameter shallow drain pan
beneath the transmission pan.
(3) Remove bolts holding front and sides of pan to
transmission.
(4) Loosen bolts holding rear of pan to transmis-
sion.
(5) Slowly separate front of pan away from trans-
mission allowing the fluid to drain into drain pan.
(6) Hold up pan and remove remaining bolts hold-
ing pan to transmission.
(7) While holding pan level, lower pan away from
transmission.
(8) Pour remaining fluid in pan into drain pan.
(9) Remove screw holding filter to valve body (Fig.
67).
(10) Separate filter from valve body and oil pump
and pour fluid in filter into drain pan.
Fig. 66 Transmission Fluid Temperature Chart
DRAUTOMATIC TRANSMISSION - 45RFE/545RFE 21 - 367
FLUID AND FILTER (Continued)

INSTALLATION
(1) Route the transmission end of the gearshift
cable through the opening in the dash panel (Fig.
72).
(2) Seat the cable grommet into the dash panel
opening.
(3) Snap the cable into the steering column
bracket so the retaining ears (Fig. 73) are engaged
and snap the cable eyelet onto the shift lever ball
stud.(4) Raise the vehicle.
(5) Place the transmission manual shift lever in
the ªPARKº detent (rearmost) position and rotate
prop shaft to ensure transmission is in PARK.
(6) Route the gearshift cable through the transmis-
sion mounting bracket and secure the cable by snap-
ping the cable retaining ears into the transmission
bracket and snapping the cable eyelet on the manual
shift lever ball stud.
(7) Lower vehicle.
(8) Lock the shift cable adjustment by pressing the
cable adjuster lock tab downward until it snaps into
place.
(9) Check for proper operation of the transmission
range sensor.
(10) Adjust the gearshift cable (Refer to 21 -
TRANSMISSION/AUTOMATIC/GEAR SHIFT
CABLE - ADJUSTMENTS) and BTSI mechanism
(Refer to 21 - TRANSMISSION/AUTOMATIC/
BRAKE TRANSMISSION SHIFT INTERLOCK SYS-
TEM - ADJUSTMENTS) as necessary.
ADJUSTMENTS
GEARSHIFT CABLE
Check adjustment by starting the engine in PARK
and NEUTRAL. Adjustment is CORRECT if the
engine starts only in these positions. Adjustment is
INCORRECT if the engine starts in one but not both
positions. If the engine starts in any position other
than PARK or NEUTRAL, or if the engine will not
start at all, the transmission range sensor may be
faulty.
Gearshift Adjustment Procedure
(1) Shift transmission into PARK.
(2) Release cable adjuster lock tab (underneath the
steering column) (Fig. 74) to unlock cable.
(3) Raise vehicle.
(4) Disengage the cable eyelet from the transmis-
sion manual shift lever.
(5) Verify transmission shift lever is in PARK
detent by moving lever fully rearward. Last rearward
detent is PARK position.
(6) Verify positive engagement of transmission
park lock by attempting to rotate propeller shaft.
Shaft will not rotate when park lock is engaged.
(7) Snap the cable eyelet onto the transmission
manual shift lever.
Fig. 72 Gearshift Cable at the Dash Panel
1 - GEARSHIFT CABLE
2 - GROMMET
Fig. 73 Gearshift Cable at Steering Column
1 - STEERING COLUMN
2 - GEARSHIFT CABLE
3 - GEARSHIFT CABLE LOCK TAB
4 - BTSI SOLENOID LOCK TAB
5 - BTSI CONNECTOR
21 - 370 AUTOMATIC TRANSMISSION - 45RFE/545RFEDR
GEARSHIFT CABLE (Continued)

(28) Install the number 2 bearing onto the under-
drive hub with outer race against the hub with petro-
leum jelly.
(29) Install the underdrive hub into the input
clutch retainer.
(30) Install the number 3 bearing into the over-
drive hub with the outer race against the hub with
petroleum jelly.
(31) Install the overdrive hub into the input clutch
retainer.
(32) Install the number 4 bearing into the reverse
hub with outer race against the hub with petroleum
jelly.
(33) Install the reverse hub into the input clutch
retainer.
(34) Install the complete reverse clutch pack.
(35) Install the reverse reaction plate and snap-
ring.
(36) Push up on reaction plate to allow reverse
clutch to move freely.
INPUT SPEED SENSOR
DESCRIPTION
The Input and Output Speed Sensors are two-wire
magnetic pickup devices that generate AC signals as
rotation occurs. They are mounted in the left side of
the transmission case and are considered primary
inputs to the Transmission Control Module (TCM).
OPERATION
The Input Speed Sensor provides information on
how fast the input shaft is rotating. As the teeth of
the input clutch hub pass by the sensor coil, an AC
voltage is generated and sent to the TCM. The TCM
interprets this information as input shaft rpm.
The Output Speed Sensor generates an AC signal
in a similar fashion, though its coil is excited by rota-
tion of the rear planetary carrier lugs. The TCM
interprets this information as output shaft rpm.
The TCM compares the input and output speed
signals to determine the following:
²Transmission gear ratio
²Speed ratio error detection
²CVI calculation
The TCM also compares the input speed signal and
the engine speed signal to determine the following:
²Torque converter clutch slippage
²Torque converter element speed ratio
REMOVAL
(1) Raise vehicle.
(2) Place a suitable fluid catch pan under the
transmission.(3) Remove the wiring connector from the input
speed sensor (Fig. 91).
(4) Remove the bolt holding the input speed sensor
to the transmission case.
(5) Remove the input speed sensor from the trans-
mission case.
INSTALLATION
(1) Install the input speed sensor into the trans-
mission case.
(2) Install the bolt to hold the input speed sensor
into the transmission case. Tighten the bolt to 11.9
N´m (105 in.lbs.).
(3) Install the wiring connector onto the input
speed sensor
(4) Verify the transmission fluid level. Add fluid as
necessary.
(5) Lower vehicle.
LINE PRESSURE (LP) SENSOR
DESCRIPTION
The TCM utilizes a closed-loop system to control
transmission line pressure. The system contains a
variable force style solenoid, the Pressure Control
Solenoid, mounted on the side of the solenoid and
pressure switch assembly. The solenoid is duty cycle
controlled by the TCM to vent the unnecessary line
pressure supplied by the oil pump back to the sump.
The system also contains a variable pressure style
sensor, the Line Pressure Sensor, which is a direct
input to the TCM. The line pressure solenoid moni-
tors the transmission line pressure and completes the
Fig. 91 Input Speed Sensor
1 - OUTPUT SPEED SENSOR
2 - LINE PRESSURE SENSOR
3 - INPUT SPEED SENSOR
21 - 382 AUTOMATIC TRANSMISSION - 45RFE/545RFEDR
INPUT CLUTCH ASSEMBLY (Continued)

feedback loop to the TCM. The TCM uses this infor-
mation to adjust its control of the pressure control
solenoid to achieve the desired line pressure.
OPERATION
The TCM calculates the desired line pressure
based upon inputs from the transmission and engine.
The TCM calculates the torque input to the trans-
mission and uses that information as the primary
input to the calculation. The line pressure is set to a
predetermined value during shifts and when the
transmission is in the PARK and NEUTRAL posi-
tions. This is done to ensure consistent shift quality.
During all other operation, the actual line pressure is
compared to the desired line pressure and adjust-
ments are made to the pressure control solenoid duty
cycle.
REMOVAL
(1) Raise vehicle.
(2) Place a suitable fluid catch pan under the
transmission.
(3) Remove the wiring connector from the line
pressure sensor (Fig. 92).
(4) Remove the bolt holding the line pressure sen-
sor to the transmission case.
(5) Remove the line pressure sensor from the
transmission case.
INSTALLATION
(1) Install the line pressure sensor into the trans-
mission case.(2) Install the bolt to hold the line pressure sensor
into the transmission case. Tighten the bolt to 11.9
N´m (105 in.lbs.).
(3) Install the wiring connector onto the line pres-
sure sensor
(4) Verify the transmission fluid level. Add fluid as
necessary.
(5) Lower vehicle.
Fig. 92 Line Pressure Sensor
1 - OUTPUT SPEED SENSOR
2 - LINE PRESSURE SENSOR
3 - INPUT SPEED SENSOR
DRAUTOMATIC TRANSMISSION - 45RFE/545RFE 21 - 383
LINE PRESSURE (LP) SENSOR (Continued)

into the appropriate oil pump valve body bore (Fig.
102) (Fig. 103).
(4) Place the separator plate onto the oil pump
body (Fig. 101).
(5) Install the screws to hold the separator plate
onto the oil pump body (Fig. 101). Tighten the screws
to 4.5 N´m (40 in.lbs.).
(6) Position the oil pump cover onto the locating
dowels (Fig. 100).
(7) Seat the two oil pump halves together and
install all bolts finger tight.
(8) Torque all bolts down slowly starting in the
center and working outward. The correct torque is
4.5 N´m (40 in.lbs.).
(9) Verify that the oil pump gears rotate freely and
smoothly.
(10) Position the reaction shaft support into the oil
pump (Fig. 100).
(11) Install and torque the bolts to hold the reac-
tion shaft support to the oil pump (Fig. 100). The cor-
rect torque is 12 N´m (105 in.lbs.).
OIL PUMP FRONT SEAL
REMOVAL
(1) Remove transmission from the vehicle.
(2) Remove the torque converter from the trans-
mission.
(3) Using a screw mounted in a slide hammer,
remove the oil pump front seal.
INSTALLATION
(1) Clean seal bore of the oil pump of any residue
or particles from the original seal.
(2) Install new oil seal in the oil pump housing
using Seal Installer C-3860-A (Fig. 104).
OUTPUT SPEED SENSOR
DESCRIPTION
The Input and Output Speed Sensors are two-wire
magnetic pickup devices that generate AC signals as
rotation occurs. They are mounted in the left side of
the transmission case and are considered primary
inputs to the Transmission Control Module (TCM).
OPERATION
The Input Speed Sensor provides information on
how fast the input shaft is rotating. As the teeth of
the input clutch hub pass by the sensor coil, an AC
voltage is generated and sent to the TCM. The TCM
interprets this information as input shaft rpm.
The Output Speed Sensor generates an AC signal
in a similar fashion, though its coil is excited by rota-
tion of the rear planetary carrier lugs. The TCM
interprets this information as output shaft rpm.
The TCM compares the input and output speed
signals to determine the following:
²Transmission gear ratio
²Speed ratio error detection
²CVI calculation
The TCM also compares the input speed signal and
the engine speed signal to determine the following:
²Torque converter clutch slippage
²Torque converter element speed ratio
REMOVAL
(1) Raise vehicle.
(2) Place a suitable fluid catch pan under the
transmission.
(3) Remove the wiring connector from the output
speed sensor (Fig. 105).
(4) Remove the bolt holding the output speed sen-
sor to the transmission case.
(5) Remove the output speed sensor from the
transmission case.
Fig. 104 Install Oil Pump Front Seal
1 - TOOL C-3860-A
DRAUTOMATIC TRANSMISSION - 45RFE/545RFE 21 - 391
OIL PUMP (Continued)

INSTALLATION
(1) Install the output speed sensor into the trans-
mission case.
(2) Install the bolt to hold the output speed sensor
into the transmission case. Tighten the bolt to 11.9
N´m (105 in.lbs.).
(3) Install the wiring connector onto the output
speed sensor
(4) Verify the transmission fluid level. Add fluid as
necessary.
(5) Lower vehicle.
TOW/HAUL OVERDRIVE
SWITCH
DESCRIPTION
The tow/haul overdrive OFF (control) switch is
located in the shift lever arm (Fig. 106). The switch
is a momentary contact device that signals the PCM
to toggle current status of the overdrive function.
OPERATION
At key-on, overdrive operation is allowed. Pressing
the switch once causes the tow/haul overdrive OFF
mode to be entered and the Tow/Haul lamp to be illu-
minated. Pressing the switch a second time causesnormal overdrive operation to be restored and the
tow/haul lamp to be turned off. The tow/haul over-
drive OFF mode defaults to ON after the ignition
switch is cycled OFF and ON. The normal position
for the control switch is the ON position. The switch
must be in this position to energize the solenoid and
allow a 3-4 upshift. The control switch indicator light
illuminates only when the tow/haul overdrive switch
is turned to the OFF position, or when illuminated
by the transmission control module.
REMOVAL
(1) Using a plastic trim tool, remove the tow/haul
overdrive off switch retainer from the shift lever (Fig.
107).
Fig. 105 Output Speed Sensor
1 - OUTPUT SPEED SENSOR
2 - LINE PRESSURE SENSOR
3 - INPUT SPEED SENSOR
Fig. 106 Tow/Haul Overdrive Off Switch
Fig. 107 Tow/Haul Overdrive Off Switch Retainer
21 - 392 AUTOMATIC TRANSMISSION - 45RFE/545RFEDR
OUTPUT SPEED SENSOR (Continued)

(9) Fill the transmission with the recommended
fluid.
TRANSMISSION CONTROL
RELAY
DESCRIPTION
The relay is supplied fused B+ voltage, energized
by the TCM, and is used to supply power to the sole-
noid pack when the transmission is in normal oper-
ating mode.
OPERATION
When the relay is ªoffº, no power is supplied to the
solenoid pack and the transmission is in ªlimp-inº
mode. After a controller reset, the TCM energizes the
relay. Prior to this, the TCM verifies that the con-
tacts are open by checking for no voltage at the
switched battery terminals. After this is verified, the
voltage at the solenoid pack pressure switches is
checked. After the relay is energized, the TCM mon-
itors the terminals to verify that the voltage is
greater than 3 volts.
TRANSMISSION RANGE
SENSOR
DESCRIPTION
The Transmission Range Sensor (TRS) is part of
the solenoid module, which is mounted to the top of
the valve body inside the transmission.
The Transmission Range Sensor (TRS) has five
switch contact pins that:
²Determine shift lever position
²Supply ground to the Starter Relay in Park and
Neutral only.
²
Supply +12 V to the backup lamps in Reverse only.
The TRS also has an integrated temperature sen-
sor (thermistor) that communicates transmission
temperature to the TCM and PCM.
OPERATION
The Transmission Range Sensor (TRS) communi-
cates shift lever position to the TCM as a combina-
tion of open and closed switches. Each shift lever
position has an assigned combination of switch states
(open/closed) that the TCM receives from four sense
circuits. The TCM interprets this information and
determines the appropriate transmission gear posi-
tion and shift schedule.
There are many possible combinations of open and
closed switches (codes). Seven of these possible codes
are related to gear position and five are recognized
as ªbetween gearº codes. This results in many codes
which shouldnever occur. These are called
ªinvalidº codes. An invalid code will result in a DTC,
and the TCM will then determine the shift lever
position based on pressure switch data. This allows
reasonably normal transmission operation with a
TRS failure.
GEAR C5 C4 C3 C2 C1
ParkCL OP OP CL CL
Temp 1CL OP OP CL OP
ReverseOP OP OP CL OP
Temp 2OP OP CL CL OP
Neutral 1OP OP CL CL CL
Neutral 2OP CL CL CL CL
Temp 3OP CL CL CL OP
DriveOP CL CL OP OP
Temp 4OP CL OP OP OP
Manual 2CL CL OP OP OP
Temp 5CL OP OP OP OP
Manual 1CL OP CL OP OP
Fig. 125 Checking Torque Converter Seating-Typical
1 - SCALE
2 - STRAIGHTEDGE
DRAUTOMATIC TRANSMISSION - 45RFE/545RFE 21 - 405
TORQUE CONVERTER (Continued)