Transmission tcc DODGE RAM 1500 1998 2.G User Guide

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)

SHIFT MECHANISM
DESCRIPTION
The gear shift mechanism provides six shift posi-
tions which are:
²Park (P)
²Reverse (R)
²Neutral (N)
²Drive (D)
²Manual second (2)
²Manual low (1)
OPERATION
MANUAL LOW (1) range provides first gear only.
Overrun braking is also provided in this range.
MANUAL SECOND (2) range provides first and sec-
ond gear only.
DRIVE range provides FIRST, SECOND, THIRD,
OVERDRIVE FOURTH, and OVERDRIVE FIFTH (if
applicable) gear ranges. The shift into OVERDRIVE
FOURTH and FIFTH (if applicable) gear ranges
occurs only after the transmission has completed the
shift into D THIRD gear range. No further movement
of the shift mechanism is required to complete the
3-4 or 4-5 (if applicable) shifts.
The FOURTH and FIFTH (if applicable) gear
upshifts occur automatically when the overdrive
selector switch is in the ON position. No upshift to
FOURTH or FIFTH (if applicable) gears will occur if
any of the following are true:
²The transmission fluid temperature is below 10É
C (50É F) or above 121É C (250É F).
²The shift to THIRD is not yet complete.
²Vehicle speed is too low for the 3-4 or 4-5 (if
applicable) shifts to occur.
Upshifts into FOURTH or FIFTH (if applicable)
will be delayed when the transmission fluid temper-
ature is below 4.5É C (40É F) or above 115.5É C (240É
F).
SOLENOID SWITCH VALVE
DESCRIPTION
The Solenoid Switch Valve (SSV) is located in the
valve body and controls the direction of the transmis-
sion fluid when the L/R-TCC solenoid is energized.
OPERATION
The Solenoid Switch Valve controls line pressure
from the LR-TCC solenoid. In 1st gear, the SSV will
be in the downshifted position, thus directing fluid to
the L/R clutch circuit. In 2nd, 3rd, 4th, and 5th (if
applicable) gears, the solenoid switch valve will be in
the upshifted position and directs the fluid into the
torque converter clutch (TCC) circuit.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.
SOLENOIDS
DESCRIPTION
The typical electrical solenoid used in automotive
applications is a linear actuator. It is a device that
produces motion in a straight line. This straight line
motion can be either forward or backward in direc-
tion, and short or long distance.
A solenoid is an electromechanical device that uses
a magnetic force to perform work. It consists of a coil
of wire, wrapped around a magnetic core made from
steel or iron, and a spring loaded, movable plunger,
which performs the work, or straight line motion.
The solenoids used in transmission applications
are attached to valves which can be classified asnor-
mally openornormally closed. Thenormally
opensolenoid valve is defined as a valve which
allows hydraulic flow when no current or voltage is
applied to the solenoid. Thenormally closedsole-
noid valve is defined as a valve which does not allow
hydraulic flow when no current or voltage is applied
to the solenoid. These valves perform hydraulic con-
trol functions for the transmission and must there-
fore be durable and tolerant of dirt particles. For
these reasons, the valves have hardened steel pop-
pets and ball valves. The solenoids operate the valves
directly, which means that the solenoids must have
very high outputs to close the valves against the siz-
able flow areas and line pressures found in current
transmissions. Fast response time is also necessary
to ensure accurate control of the transmission.
The strength of the magnetic field is the primary
force that determines the speed of operation in a par-
ticular solenoid design. A stronger magnetic field will
cause the plunger to move at a greater speed than a
weaker one. There are basically two ways to increase
the force of the magnetic field:
1. Increase the amount of current applied to the
coil or
2. Increase the number of turns of wire in the coil.
The most common practice is to increase the num-
ber of turns by using thin wire that can completely
fill the available space within the solenoid housing.
The strength of the spring and the length of the
plunger also contribute to the response speed possi-
ble by a particular solenoid design.
21 - 398 AUTOMATIC TRANSMISSION - 45RFE/545RFEDR

STATOR
The stator assembly (Fig. 120) is mounted on a sta-
tionary shaft which is an integral part of the oil
pump. The stator is located between the impeller and
turbine within the torque converter case (Fig. 121).
The stator contains an over-running clutch, which
allows the stator to rotate only in a clockwise direc-
tion. When the stator is locked against the over-run-
ning clutch, the torque multiplication feature of the
torque converter is operational.
TORQUE CONVERTER CLUTCH (TCC)
The TCC (Fig. 122) was installed to improve the
efficiency of the torque converter that is lost to the
slippage of the fluid coupling. Although the fluid cou-
pling provides smooth, shock-free power transfer, it is
natural for all fluid couplings to slip. If the impeller
and turbine were mechanically locked together, a
zero slippage condition could be obtained. A hydraulic
piston with friction material was added to the tur-
bine assembly to provide this mechanical lock-up.
In order to reduce heat build-up in the transmis-
sion and buffer the powertrain against torsional
vibrations, the TCM can duty cycle the L/R-CC Sole-
noid to achieve a smooth application of the torque
converter clutch. This function, referred to as Elec-
tronically Modulated Converter Clutch (EMCC) can
occur at various times depending on the following
variables:
²Shift lever position
²Current gear range
²Transmission fluid temperature
²Engine coolant temperature
²Input speed
²Throttle angle²Engine speed
Fig. 120 Stator Components
1 - CAM (OUTER RACE)
2 - ROLLER
3 - SPRING
4 - INNER RACE
Fig. 121 Stator Location
1-STATOR
2 - IMPELLER
3 - FLUID FLOW
4 - TURBINE
Fig. 122 Torque Converter Clutch (TCC)
1 - IMPELLER FRONT COVER
2 - THRUST WASHER ASSEMBLY
3 - IMPELLER
4-STATOR
5 - TURBINE
6 - PISTON
7 - FRICTION DISC
21 - 402 AUTOMATIC TRANSMISSION - 45RFE/545RFEDR
TORQUE CONVERTER (Continued)

OPERATION
The converter impeller (Fig. 123) (driving member),
which is integral to the converter housing and bolted
to the engine drive plate, rotates at engine speed.
The converter turbine (driven member), which reacts
from fluid pressure generated by the impeller, rotates
and turns the transmission input shaft.
TURBINE
As the fluid that was put into motion by the impel-
ler blades strikes the blades of the turbine, some of
the energy and rotational force is transferred into the
turbine and the input shaft. This causes both of them
(turbine and input shaft) to rotate in a clockwise
direction following the impeller. As the fluid is leav-
ing the trailing edges of the turbine's blades it con-
tinues in a ªhinderingº direction back toward the
impeller. If the fluid is not redirected before it strikes
the impeller, it will strike the impeller in such a
direction that it would tend to slow it down.
STATOR
Torque multiplication is achieved by locking the
stator's over-running clutch to its shaft (Fig. 124).
Under stall conditions (the turbine is stationary), the
oil leaving the turbine blades strikes the face of the
stator blades and tries to rotate them in a counter-
clockwise direction. When this happens the over-run-ning clutch of the stator locks and holds the stator
from rotating. With the stator locked, the oil strikes
the stator blades and is redirected into a ªhelpingº
direction before it enters the impeller. This circula-
tion of oil from impeller to turbine, turbine to stator,
and stator to impeller, can produce a maximum
torque multiplication of about 2.4:1. As the turbine
begins to match the speed of the impeller, the fluid
that was hitting the stator in such as way as to
cause it to lock-up is no longer doing so. In this con-
dition of operation, the stator begins to free wheel
and the converter acts as a fluid coupling.
TORQUE CONVERTER CLUTCH (TCC)
In a standard torque converter, the impeller and
turbine are rotating at about the same speed and the
stator is freewheeling, providing no torque multipli-
cation. By applying the turbine's piston and friction
material to the front cover, a total converter engage-
ment can be obtained. The result of this engagement
is a direct 1:1 mechanical link between the engine
and the transmission.
The clutch can be engaged in second, third, fourth,
and fifth (if appicable) gear ranges depending on
overdrive control switch position. If the overdrive
control switch is in the normal ON position, the
clutch will engage after the shift to fourth gear. If the
Fig. 123 Torque Converter Fluid Operation - Typical
1 - APPLY PRESSURE 3 - RELEASE PRESSURE
2 - THE PISTON MOVES SLIGHTLY FORWARD 4 - THE PISTON MOVES SLIGHTLY REARWARD
DRAUTOMATIC TRANSMISSION - 45RFE/545RFE 21 - 403
TORQUE CONVERTER (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)

²A flashing operating mode LED for the desired
gear indicates that a shift to that position has been
requested, but all of the driver controllable conditions
have not been met. This is in an attempt to notify the
driver that the transmission needs to be put into NEU-
TRAL, the vehicle speed is too great, or some other con-
dition outlined (other than a diagnostic failure that
would prevent this shift) elsewhere (Refer to 8 - ELEC-
TRICAL/ELECTRONIC CONTROL MODULES/TRANS-
FER CASE CONTROL MODULE - OPERATION) is not
met. Note that this flashing will continue indefinitely
until the conditions are eventually met, or the selector
switch position is changed, or if diagnostic routines no
longer allow the requested shift.
²If the driver attempts to make a shift into transfer
case NEUTRAL, and any of the driver controllable con-
ditions are not met, the request will be ignored until all
of the conditions are met or until the NEUTRAL select
button is released. Additionally the neutral lamp will
flash, or begin to flash while the button is depressed
and operator controllable conditions are not being met.
All of the LED's except the Neutral will flash if any of
the operator controllable conditions for shifting are not
met while the Neutral button is depressed. This9toggle9
type of feature is necessary because the TCCM would
interpret another request immediately after the shift
into transfer case NEUTRAL has completed.
²No LED's illuminated indicate a fault in the
transfer case control system.
SHIFT MOTOR
DESCRIPTION
The shift motor (Fig. 85) consists of a permanent
magnet D.C. motor with gear reduction to convert a
high speed-low torque device into a low speed-high
torque device. The output of the device is coupled to a
shaft which internally moves the mode and range forks
that change the transfer case operating ranges. The
motor is rated at 25 amps maximum at 72É F with 10
volts at the motor leads.
OPERATION
The transfer case shift motor responds to the Transfer
Case Control Module (TCCM) commands to move the
transfer case shift sector bi-directionally, as required, to
obtain the transfer case operating mode indicated by
the instrument panel mounted selector switch.
REMOVAL
NOTE: New shift motor assemblies are shipped in the
2WD/AWD position. If a new shift motor assembly will
be installed, it will be necessary to shift the transfer
case to the 2WD/AWD position prior to motor removal.
(1) Raise the vehicle on a suitable hoist.
(2) Disengage the wiring connectors from the shift
motor and mode sensor.
(3) Remove the bolts holding the shift motor and
mode sensor assembly onto the transfer case.
(4) Separate the shift motor and mode sensor
assembly from the transfer case.
INSTALLATION
(1) Verify that the shift sector o-ring is clean and
properly positioned over the shift sector and against
the transfer case.
NOTE: Verify that the shift motor position and sec-
tor shaft orientation are aligned. It may be neces-
sary to manually shift the transfer case if the shift
motor and sector shaft are not aligned.
(2) Position the shift motor and mode sensor
assembly onto the transfer case.
(3) Install the bolts to hold the assembly onto the
transfer case. Tighten the bolts to 16-24 N´m (12-18
ft.lbs.).
CAUTION: If the original shift motor and mode sen-
sor assembly bolts are reused, be sure to use
MoparTLock & Seal or LoctiteŸ 242 to replenish
the lock patch material originally found on the bolts
(4) Engage the wiring connectors to the shift motor
and mode sensor.
(5) Refill the transfer case as necessary.
(6) Lower vehicle and verify transfer case opera-
tion.
Fig. 85 Shift Motor - Shown Inverted - Typical
1 - SHIFT MOTOR
DRTRANSFER CASE - NV243 21 - 511
SELECTOR SWITCH (Continued)

OPERATION
As the position of the selector switch varies, the
resistance between the Mode Sensor supply voltage
pin and the Mode Sensor output will vary. Hardware,
software, and calibrations within the Transfer Case
Control Module (TCCM) are provided that interpret
the selector switch resistance as given in the table
below: SELECTOR SWITCH INTERPRETATION
SELECTOR SWITCH INTERPRETATION
Step Resistance
Range (ohms)Required
Interpretation
A <200 Shorted
B 400-700 NEUTRAL
C 1050-1450 4LO
D 1850-2300 4H
E 3050-5950 AWD (Default)
F 9.5-12.5K In between
positions
G >15.5K Open
For resistances between the ranges B-E shown for
each valid position (T-Case NEUTRAL, 4LO, 4HI,
AWD), the TCCM may interpret the resistance as:
²either of the neighboring valid positions.
²as an invalid fault position.
For resistances between the ranges E and F shown
for AWD and in-between positions, the TCCM may
interpret the resistance as:
²the AWD position.
²an invalid fault position.
²a valid in-between position.
For resistances between the ranges F and G shown
for in-between positions and fault condition (open),
the TCCM may interpret the resistance as:
²a valid in-between position.
²an invalid fault position.
For resistances between the ranges A and B shown
for the fault condition (short) and , T-Case NEU-
TRAL, the TCCM may interpret the resistance as:²the T-Case NEUTRAL position.
²an invalid fault position.
The LED's in the selector assembly are illuminat-
ed/flashed in the following manner to indicate a par-
ticular condition or state.
²A solidly illuminated LED indicates a success-
fully completed shift and the current operating mode
of the transfer case. While a shift has been requested
but not yet completed, the LED for the desired trans-
fer case position is flashed.
²A flashing operating mode LED for the desired
gear indicates that a shift to that position has been
requested, but all of the driver controllable conditions
have not been met. This is in an attempt to notify
the driver that the transmission needs to be put into
NEUTRAL, the vehicle speed is too great, or some
other condition outlined (other than a diagnostic fail-
ure that would prevent this shift) elsewhere (Refer to
8 - ELECTRICAL/ELECTRONIC CONTROL MOD-
ULES/TRANSFER CASE CONTROL MODULE -
OPERATION) is not met. Note that this flashing will
continue indefinitely until the conditions are eventu-
ally met, or the selector switch position is changed,
or if diagnostic routines no longer allow the
requested shift.
²If the driver attempts to make a shift into trans-
fer case NEUTRAL, and any of the driver controlla-
ble conditions are not met, the request will be
ignored until all of the conditions are met or until
the NEUTRAL select button is released. Additionally
the neutral lamp will flash, or begin to flash while
the button is depressed and operator controllable
conditions are not being met. All of the LED's except
the Neutral will flash if any of the operator control-
lable conditions for shifting are not met while the
Neutral button is depressed. This9toggle9type of fea-
ture is necessary because the TCCM would interpret
another request immediately after the shift into
transfer case NEUTRAL has completed.
²No LED's illuminated indicate a fault in the
transfer case control system.
21 - 540 TRANSFER CASE - NV244 GENIIDR
SELECTOR SWITCH (Continued)

have not been met. This is in an attempt to notify
the driver that the transmission needs to be put into
NEUTRAL, the vehicle speed is too great, or some
other condition outlined (other than a diagnostic fail-
ure that would prevent this shift) elsewhere (Refer to
8 - ELECTRICAL/ELECTRONIC CONTROL MOD-
ULES/TRANSFER CASE CONTROL MODULE -
OPERATION) is not met. Note that this flashing will
continue indefinitely until the conditions are eventu-
ally met, or the selector switch position is changed,
or if diagnostic routines no longer allow the
requested shift.
²
If the driver attempts to make a shift into transfer
case NEUTRAL, and any of the driver controllable con-
ditions are not met, the request will be ignored until all
of the conditions are met or until the NEUTRAL select
button is released. Additionally the neutral lamp will
flash, or begin to flash while the button is depressed
and operator controllable conditions are not being met.
All of the LED's except the Neutral will flash if any of
the operator controllable conditions for shifting are not
met while the Neutral button is depressed. This9toggle9
type of feature is necessary because the TCCM would
interpret another request immediately after the shift
into transfer case NEUTRAL has completed.
²No LED's illuminated indicate a fault in the
transfer case control system.
SHIFT MOTOR
DESCRIPTION
The shift motor (Fig. 96) consists of a permanent
magnet D.C. motor with gear reduction to convert a
high speed-low torque device into a low speed-high
torque device. The output of the device is coupled to
a shaft which internally moves the mode and range
forks that change the transfer case operating ranges.
The motor is rated at 25 amps maximum at 72É F
with 10 volts at the motor leads.
OPERATION
The transfer case shift motor responds to the
Transfer Case Control Module (TCCM) commands to
move the transfer case shift sector bi-directionally, as
required, to obtain the transfer case operating mode
indicated by the instrument panel mounted selector
switch.
REMOVAL
NOTE: New shift motor assemblies are shipped in
the 2WD/AWD position. If a new shift motor assem-
bly will be installed, it will be necessary to shift the
transfer case to the 2WD/AWD position prior to
motor removal.(1) Raise the vehicle on a suitable hoist.
(2) Disengage the wiring connectors from the shift
motor and mode sensor.
(3) Remove the bolts holding the shift motor and
mode sensor assembly onto the transfer case.
(4) Separate the shift motor and mode sensor
assembly from the transfer case.
INSTALLATION
(1) Verify that the shift sector o-ring is clean and
properly positioned over the shift sector and against
the transfer case.
NOTE: Verify that the shift motor position and sec-
tor shaft orientation are aligned. It may be neces-
sary to manually shift the transfer case if the shift
motor and sector shaft are not aligned.
(2) Position the shift motor and mode sensor
assembly onto the transfer case.
(3) Install the bolts to hold the assembly onto the
transfer case. Tighten the bolts to 16-24 N´m (12-18
ft.lbs.).
CAUTION: If the original shift motor and mode sen-
sor assembly bolts are reused, be sure to use
MoparTLock & Seal or LoctiteŸ 242 to replenish
the lock patch material originally found on the bolts
(4) Engage the wiring connectors to the shift motor
and mode sensor.
(5) Refill the transfer case as necessary.
(6) Lower vehicle and verify transfer case
operation.
Fig. 96 Shift Motor - Shown Inverted - Typical
1 - SHIFT MOTOR
DRTRANSFER CASE - NV273 21 - 575
SELECTOR SWITCH (Continued)