DODGE RAM 1500 1998 2.G Workshop Manual

(3) Remove the front propeller shaft seal boot (Fig.
80).
(4) Remove the front output shaft seal slinger by
bending (Fig. 81) the slinger ears away from the
transfer case.
(5) Using a suitable pry tool (Fig. 82), remove the
slinger from the output shaft using care not to dam-
age the shaft.
(6) Using a screw and a slide hammer, remove the
front output shaft seal.
INSTALLATION
(1) Install the new front output shaft seal with
Installer MB991168A
(2) Install the front output shaft seal slinger with
Installer 8840. Install the slinger onto the shaft until
the tool contacts the rear of the output shaft.
(3) Install a new seal boot clamp onto the seal
boot.
(4) Install the seal boot and clamp onto the slinger
hub and tighten the clamp with Crimp Tool
C-4975-A.
(5) Install front propeller shaft (Refer to 3 - DIF-
FERENTIAL & DRIVELINE/PROPELLER SHAFT/
PROPELLER SHAFT - INSTALLATION).Fig. 80 Remove Seal Boot
1 - SEAL BOOT
2 - SEAL SLINGER
Fig. 81 Bend Slinger Ears
1 - SLINGER
2 - BEND UPWARD
Fig. 82 Remove Slinger From Shaft
1 - SLINGER
2-PRYTOOL
21 - 508 TRANSFER CASE - NV243DR
FRONT OUTPUT SHAFT SEAL (Continued)

MODE SENSOR
DESCRIPTION
The transfer case mode sensor (Fig. 83) is an elec-
tronic device whose output can be interpreted to indi-
cate the shift motor shaft's rotary position. The
sensor consists of a magnetic ring and four Hall
Effect Transistors to create a 4 channel digital device
(non-contacting) whose output converts the motor
shaft position into a coded signal. The TCCM must
supply 5VDC (+/- 0.5v) to the sensor and monitor the
shift motor position. The four channels are denoted
A, B, C, and D. The sensor is mechanically linked to
the shaft of the cam which causes the transfer case
shifting. The mode sensor draws less than 53 mA.
OPERATION
During normal vehicle operation, the Transfer Case
Control Module (TCCM) monitors the mode sensor
outputs at least every 250 (+/-50) milliseconds when
the shift motor is stationary and 400 microseconds
when the shift motor is active. A mode sensor signal
between 3.8 Volts and 0.8 Volts is considered to be
undefined.
Refer to SECTOR ANGLES vs. TRANSFER CASE
POSITION for the relative angles of the transfer case
shift sector versus the interpreted transfer case gear
operating mode. Refer to MODE SENSOR CHAN-
NEL STATES for the sensor codes returned to the
TCCM for each transfer case mode sensor position.
The various between gears positions can also be
referred as the transfer case's coarse position. These
coarse positions come into play during shift attempts.SECTOR ANGLES VS. TRANSFER CASE POSITION
Shaft Angle (Degrees) Transfer Case Position
+40 4LO
+20 N
0 2WD/AWD
-20 4HI
MODE SENSOR CHANNEL STATES
Transfer Case
Angle (degrees)Sensor Channel A Sensor Channel B Sensor Channel C Sensor Channel D
Between Gears H H L H
+40 (4LO) H H L L
Between Gears H H L H
Between Gears H L L H
+20 (NEUTRAL) H L L L
Between Gears H L L H
Between Gears H L H H
0 (2WD/AWD) H L H L
Between Gears H L H H
Between Gears L L H H
-20 (4HI) L L H L
Between Gears L L H H
Between Gears L H H H
Fig. 83 Mode Sensor
1 - MODE SENSOR
DRTRANSFER CASE - NV243 21 - 509

SELECTOR SWITCH
DESCRIPTION
The selector switch assembly (Fig. 84) is mounted
in the left side of the vehicle's Instrument Panel (IP)
and consists of a rotary knob connected to a resistive
network for the mode and range shift selections. Also
located in this assembly is a recessed, normally open
momentary switch for making shifts into and out of
transfer case NEUTRAL. A pen, or similar instru-
ment, is used to make a NEUTRAL shift selection,
thus reducing the likelihood of an inadvertent shift
request.
The selector switch also contains four light emit-
ting diode's (LED's) to indicate the transfer case posi-
tion and whether a shift is in progress.
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 INTERPRETATIONSELECTOR SWITCH INTERPRETATION
Step Resistance
Range (ohms)Required
Interpretation
A <200 Shorted
B 400-700 NEUTRAL
C 1050-1450 4LO
D 1850-2300 4HI
E 3050-5950 2WD (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,
2WD), 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 2WD and in-between positions, the TCCM may
interpret the resistance as:
²the 2WD 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.
Fig. 84 Transfer Case Selector Switch
1 - SELECTOR SWITCH
21 - 510 TRANSFER CASE - NV243DR

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)

TRANSFER CASE - NV244 GENII
TABLE OF CONTENTS
page page
TRANSFER CASE - NV244 GENII
DESCRIPTION........................512
OPERATION..........................513
DIAGNOSIS AND TESTING - TRANSFER
CASE - NV244.......................513
REMOVAL............................514
DISASSEMBLY........................514
CLEANING...........................523
INSPECTION.........................523
ASSEMBLY...........................525
INSTALLATION........................534
SPECIFICATIONS
TRANSFER CASE - NV244 GENII........535
SPECIAL TOOLS
TRANSFER CASE - NV244 GENII........535
EXTENSION HOUSING SEAL
REMOVAL............................536
INSTALLATION........................536FLUID
STANDARD PROCEDURE - FLUID DRAIN AND
REFILL............................537
FRONT OUTPUT SHAFT SEAL
REMOVAL............................537
INSTALLATION........................538
MODE SENSOR
DESCRIPTION........................538
OPERATION..........................539
SELECTOR SWITCH
DESCRIPTION........................539
OPERATION..........................540
SHIFT MOTOR
DESCRIPTION........................541
OPERATION..........................541
REMOVAL............................541
INSTALLATION........................541
TRANSFER CASE - NV244
GENII
DESCRIPTION
The NV244 GENII is an electronically controlled
full and part-time transfer case with no two wheel
drive operation.
A differential in the transfer case is used to control
torque transfer to the front and rear axles. A low
range gear reduction system provides increased low
speed torque capability for off road operation. The
low range provides a 2.72:1 reduction ratio.
The geartrain is mounted in two aluminum case
halves attached with bolts. The mainshaft front and
rear bearings are mounted in aluminum retainer
housings bolted to the case halves.
OPERATING RANGES
NV244 GENII operating ranges are:
²AWD(All-Wheel Drive)
²4HI (Part-time)
²4LO
²NEUTRAL
The AWD mode can be used at any time and on
any road surface.The 4HI (Part-time) and 4LO ranges are for off
road use only. The only time these ranges can be
used is when the road surface is covered with snow,
ice, or other loose slippery material.
SHIFT MECHANISM
Operating ranges are selected with a dash
mounted shift selector switch. The shift selector
switch provides a input to the Transfer Case Control
Module (TCCM) to indicate the driver's desire to
change operating ranges. The TCCM uses this input,
along with the input from the transfer case mounted
mode sensor and information from the vehicle's bus,
to determine if a shift is permitted. If the TCCM
decides the shift is permitted, the TCCM controls the
shift motor, mounted to the exterior of the transfer
case, to perform the shift.
21 - 512 TRANSFER CASE - NV244 GENIIDR

IDENTIFICATION
A circular ID tag is attached to the rear case of
each transfer case (Fig. 1). The ID tag provides the
transfer case model number, assembly number, serial
number, and low range ratio.
The transfer case serial number also represents
the date of build.
OPERATION
The input gear is splined to the transmission out-
put shaft. The input gear drives the mainshaft
through the planetary assembly and range sleeve.
The front output shaft is operated by a drive chain
that connects the shaft to a drive sprocket on the
mainshaft. The drive sprocket is splined to a differ-
ential assembly. Depending on the position of the
mode fork and sleeve, the front output shaft is driven
directly by the mainshaft or through the differential.
The mode fork operates the mode sleeve and hub.
The sleeve and hub are not equipped with a synchro-
nizer mechanism for shifting.
DIAGNOSIS AND TESTING - TRANSFER CASE - NV244
DIAGNOSIS CHART
CONDITION POSSIBLE CAUSE CORRECTION
Transfer case difficult to shift or will
not shift into desired range.1) Transfer case electronically
controlled shift system malfunction.1) Verify proper operation per the
appropriate diagnostic manual.
2) Insufficient or incorrect lubricant. 2) Drain and refill transfer case with
the correct quantity of MoparTAT F
+4, Automatic Transmission Fluid.
3) Internal transfer case
components binding, worn, or
damaged.3) Repair or replace components as
necessary.
Transfer case noisy in all drive
modes.1) Insufficient or incorrect lubricant. 1) Drain and refill transfer case with
the correct quantity of MoparTAT F
+4, Automatic Transmission Fluid.
2) Internal transfer case
components binding, worn, or
damaged.2) Repair or replace components as
necessary.
Transfer case noisy while in, or
jumps out of, 4LO.1) Transfer case not completely
engaged in 4LO position.1) While rolling 2-3 MPH and the
transmission in NEUTRAL, or the
clutch depressed on vehicles
equipped with a manual
transmission, shift the transfer case
to the AWD or 4HI position, and
then back into the 4LO position.
2) Range fork damaged, inserts
worn, or fork is binding on the shift
rail.2) Repair or replace components as
necessary.
3) Low range gear worn or
damaged.3) Repair or replace components as
necessary.
Fig. 1 Fill/Drain Plug And I.D. Tag Locations
1 - I.D. TAG
2 - FILL PLUG
3 - DRAIN PLUG
DRTRANSFER CASE - NV244 GENII 21 - 513
TRANSFER CASE - NV244 GENII (Continued)

CONDITION POSSIBLE CAUSE CORRECTION
Lubricant leaking from transfer case
seals or vent.1) Transfer case overfilled. 1) Drain lubricant to the correct
level.
2) Transfer case vent closed or
restricted.2) Clean or replace vent as
necessary.
3) Transfer case seals damaged or
installed incorrectly.3) Replace suspect seal.
Transfer case will not shift through
4HI (Part-time) range.1) Incomplete shift due to drivetrain
torque load.1) Drive in a straight line and
momentarily release the accelerator
pedal to complete the shift.
2) Incorrect tire pressure. 2) Correct tire pressure as
necessary.
3) Excessive tire wear. 3) Correct tire condition as
necessary.
4) Excessive vehicle loading. 4) Correct as necessary.
REMOVAL
(1) Shift transfer case into AWD.
(2) Raise vehicle.
(3) Drain transfer case lubricant.
(4) Mark front and rear propeller shafts for align-
ment reference.
(5) Support transmission with jack stand.
(6)
Remove the transfer case skid plate, if equipped.
(7) Disconnect front and rear propeller shafts at
transfer case.
(8) Disconnect transfer case shift motor and mode
sensor wire connectors.
(9) Disconnect transfer case vent hose.
(10) Support transfer case with transmission jack.
(11) Secure transfer case to jack with chains.
(12) Remove nuts attaching transfer case to trans-
mission (Fig. 2).(13) Pull transfer case and jack rearward to disen-
gage transfer case.
(14) Remove transfer case from under vehicle.
DISASSEMBLY
Position transfer case in a shallow drain pan.
Remove drain plug and drain any remaining lubri-
cant remaining in case.
SHIFT MOTOR ASSEMBLY AND FRONT OUTPUT
SHAFT SEAL
(1) Remove the bolts (Fig. 3) which hold the shift
motor and mode sensor assembly to the transfer
case.
Fig. 2 Remove Transfer Case - Typical
1 - TRANSMISSION
2 - TRANSFER CASE
3 - MODE SENSOR CONNECTOR
Fig. 3 Remove the Shift Motor and Mode Sensor
Assembly Bolts - Typical
1 - TRANSFER CASE
2 - SHIFT MOTOR AND MODE SENSOR ASSEMBLY
3 - BOLT
21 - 514 TRANSFER CASE - NV244 GENIIDR
TRANSFER CASE - NV244 GENII (Continued)

(2) Remove the shift motor and mode sensor
assembly from the transfer case.
(3) Remove the front propeller shaft seal boot
retaining clamp (Fig. 4).
(4) Remove the front propeller shaft seal boot (Fig.
5).(5) Remove the front output shaft seal slinger by
bending (Fig. 6) the slinger away from the transfer
case.
(6) Using a suitable pry tool, remove the slinger
from the output shaft using care not to damage the
shaft.
(7) Using a screw and a slide hammer, remove the
front output shaft seal.
REAR EXTENSION
(1) Remove rear extension bolts (Fig. 7).
Fig. 7 Remove Rear Extension Bolts
1 - EXTENSION HOUSING
2 - TRANSFER CASE
Fig. 4 Remove Boot Clamp
1 - SEAL BOOT
2 - CLAMP
Fig. 5 Remove Seal Boot
1 - SEAL BOOT
2 - SEAL SLINGER
Fig. 6 Bend Slinger Upward
1 - SEAL SLINGER
2 - BEND UPWARD
DRTRANSFER CASE - NV244 GENII 21 - 515
TRANSFER CASE - NV244 GENII (Continued)

(2) Remove rear extension housing (Fig. 8). Tap
extension once or twice with a plastic mallet to break
sealer bead and loosen it.
(3) Remove output bearing retaining ring with
heavy duty snap-ring pliers (Fig. 9).
OIL PUMP AND REAR CASE
(1) Remove rear case-to-front case bolts (Fig. 10).
(2) Loosen rear case with pry tool to break sealer
bead. Insert tool in slot at each end of case (Fig. 11).
(3) Unseat rear case from alignment dowels.
CAUTION: Do not remove the bolts holding the oil
pump cover to the rear case half. The oil pump
cover is aligned to the rear output shaft inner bear-
ing race and will become mis-aligned if the bolts
are loosened. If the transfer case failure has gener-
ated any debris which may have become trapped in
the oil pump. the rear case and oil pump assembly
MUST be replaced.
Fig. 8 Remove Rear Extension
1 - EXTENSION HOUSING
2 - TRANSFER CASE
3 - PRY SLOT
Fig. 9 Remove Output Shaft Retaining Ring
1 - REAR OUTPUT SHAFT
2 - OUTPUT SHAFT BEARING
3 - RETAINING RING
4 - TRANSFER CASE
Fig. 10 Remove Case Bolts
1 - REAR CASE
2 - FRONT CASE
3 - BOLT
Fig. 11 Loosen Case Halves
1 - REAR CASE
2 - FRONT CASE
3 - PRY SLOTS
21 - 516 TRANSFER CASE - NV244 GENIIDR
TRANSFER CASE - NV244 GENII (Continued)

(4) Remove rear case and oil pump assembly from
front case (Fig. 12).
(5) Remove the oil pump pickup tube.
FRONT OUTPUT SHAFT AND DRIVE CHAIN
(1) Remove shift rail spring (Fig. 13).(2) Remove front sprocket retaining ring (Fig. 14).
(3) Remove the mode fork (Fig. 15) and sleeve
from the shift rail and mainshaft.
Fig. 12 Remove Rear Case
1 - REAR CASE
2 - FRONT CASE
Fig. 13 Remove Shift Rail Spring
1 - SHIFT RAIL
2 - SPRING
Fig. 14 Removing Front Sprocket Retaining Ring
1 - FRONT SPROCKET
2 - RETAINING RING
3 - FRONT OUTPUT SHAFT
Fig. 15 Remove Mode Fork and Sleeve
1 - SHIFT RAIL
2 - MODE FORK
3 - MODE SLEEVE
DRTRANSFER CASE - NV244 GENII 21 - 517
TRANSFER CASE - NV244 GENII (Continued)