1998 DODGE RAM 1500 Drive shaft

TURBINE
The turbine (Fig. 119) is the output, or driven,
member of the converter. The turbine is mounted
within the housing opposite the impeller, but is not
attached to the housing. The input shaft is inserted
through the center of the impeller and splined into
the turbine. The design of the turbine is similar to
the impeller, except the blades of the turbine are
curved in the opposite direction.
Fig. 119 Turbine
1 - TURBINE VANE 4 - PORTION OF TORQUE CONVERTER COVER
2 - ENGINE ROTATION 5 - ENGINE ROTATION
3 - INPUT SHAFT 6 - OIL FLOW WITHIN TURBINE SECTION
DRAUTOMATIC TRANSMISSION - 45RFE/545RFE 21 - 401
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)

TRANSFER CASE - NV241 GENII
TABLE OF CONTENTS
page page
TRANSFER CASE - NV241 GENII
DESCRIPTION........................415
OPERATION..........................415
DIAGNOSIS AND TESTING - TRANSFER
CASE - NV241 GENII..................416
REMOVAL............................417
DISASSEMBLY........................417
CLEANING...........................426
INSPECTION.........................426
ASSEMBLY...........................428
INSTALLATION........................438
SPECIFICATIONS
TRANSFER CASE - NV241 GENII........438
SPECIAL TOOLS
TRANSFER CASE - NV241/NV243........439
EXTENSION HOUSING BUSHING AND SEAL
REMOVAL............................440INSTALLATION........................440
FLUID
STANDARD PROCEDURE - FLUID DRAIN AND
REFILL............................441
FRONT OUTPUT SHAFT SEAL
REMOVAL............................441
INSTALLATION........................442
POSITION SENSOR
DESCRIPTION........................442
OPERATION..........................442
REMOVAL............................443
INSTALLATION........................443
SHIFT LEVER
REMOVAL............................444
INSTALLATION........................445
ADJUSTMENTS
ADJUSTMENT - SHIFT LEVER..........446
TRANSFER CASE - NV241
GENII
DESCRIPTION
The NV241 GENII transfer case is a part-time
transfer case with a low-range gear system. It pro-
vides three operating ranges plus a NEUTRAL posi-
tion. The low range position provides a gear
reduction ratio of 2.72:1 for increased low speed
torque capability.
The gear cases and extension are all of aluminum
(Fig. 1). Drive sprockets and an interconnecting drive
chain are used to transmit engine torque to the front/
rear propeller shafts. The mainshaft, input gear and
front output shaft are supported by ball and needle
bearings.
IDENTIFICATION
An identification tag (Fig. 2) is attached to the rear
case of every transfer case. The 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
OPERATING RANGE
Transfer case operating ranges are:
²2H (2-wheel drive)²4H (4-wheel drive)
²4LO (4-wheel drive low range)
The 2H range is for use on any road surface at any
time.
The 4H and 4LO ranges are for off road use only.
They are not for use on hard surface roads. The only
exception being when the road surface is covered by
ice and snow.
The low range reduction gear system is operative
in 4LO range only. This range is for extra pulling
Fig. 1 Transfer Case - Front View
1 - TRANSFER CASE
2 - MANUAL LEVER
3 - POSITION SENSOR
DRTRANSFER CASE - NV241 GENII 21 - 415

power in off road situations. Low range reduction
ratio is 2.72:1.
SHIFT MECHANISM
The transfer case is operated by an adjustable floor
mounted shift linkage. The transfer case shift lever
is directly attached to the shift sector. The sectoroperates the range and mode forks within the trans-
fer case.
A straight line shift pattern is used with a NEU-
TRAL detent. Lever range positions are imprinted in
the shift knob.
SHIFTING
The transfer case can be shifted between the 2H
and 4H operating ranges while the vehicle is in
motion. The vehicle must have the transmission
placed in NEUTRAL, or the clutch depressed in the
case of a manual transmission, and be moving less
than 2-3 MPH when shifting into and out of the 4L
operating range.
DIAGNOSIS AND TESTING - TRANSFER CASE -
NV241 GENII
Before beginning repair on a suspected transfer
case malfunction, check all other driveline compo-
nents beforehand.
The actual cause of a problem may be related to
such items as: front hubs, axles, propeller shafts,
wheels and tires, transmission, or clutch instead. If
all other driveline components are in good condition
and operating properly, refer to the Diagnosis Chart
for further information.
DIAGNOSIS CHART
Condition Possible Cause Correction
Transfer Case difficult to shift or will
not shift into desired range.1) Vehicle speed too great to permit
shifting.1) Stop vehicle and shift into
desired range. Or, reduce speed to
below 3-4 km/h (2-3 mph) before
attempting the shift.
2) If vehicle was operated for an
extended period in 4H on a dry
paved surface, the driveline torque
load may be causing a bind.2) Stop vehicle and shift the
transmission into neutral. Shift the
transfer case to 2H and operate
vehicle in 2H on dry paved
surfaces.
3) Transfer case external shift
linkage binding.3) Lubricate, repair, or replace
linkage bushings, or tighten loose
components as necessary.
4) Insufficient or incorrect lubricant. 4) Drain and refill to edge of fill hole
with MoparTATF +4, Automatic
Transmission fluid.
5) Internal components binding,
worn, or damaged.5) Disassemble the transfer case
and replace worn or damaged
components as necessary.
Transfer Case noisy in all operating
ranges.1) Insufficient or incorrect lubricant. 1) Drain and refill to edge of fill hole
with MoparTATF +4, Automatic
Transmission fluid.
Fig. 2 Transfer Case - Rear View
1 - TRANSFER CASE
2 - IDENTIFICATION TAG
21 - 416 TRANSFER CASE - NV241 GENIIDR
TRANSFER CASE - NV241 GENII (Continued)

Condition Possible Cause Correction
Noisy in, or jumps out of, four wheel
drive low range.1) Transfer case not completely
engaged in 4L position.1) With the transmission in
NEUTRAL, or the clutch depressed
in the case of a manual
transmission and the vehicle moving
under 3-4 km/h (2-3 mph), shift the
transfer case to NEUTRAL and then
shift into the 4L position.
2) Shift linkage out of adjustment. 2) Adjust linkage.
3) Shift linkage loose or binding. 3) Tighten, lubricate, or repair
linkage as necessary.
4) Range fork damaged, inserts
worn, or fork is binding on the shift
rail.4) Disassemble unit and repair as
necessary.
5) Low range gear worn or
damaged.5) Disassemble unit and repair as
necessary.
Lubricant leaking from output shaft
seal or vent.1) Transfer case overfilled. 1) Drain lubricant to the correct
level.
2) Vent closed or restricted. 2) Clear or replace vent as
necessary.
3) Output shaft seals damaged or
installed incorrectly.3) Replace seal as necessary.
Check to ensure that another
component, the propeller shaft slip
yoke for example, is not causing
damage to seal.
Abnormal tire wear. 1) Extended operation on hard, dry
surfaces in the 4H position.1) Operate vehicle in the 2H
position on hard, dry surfaces.
REMOVAL
(1) Raise and support vehicle.
(2) Remove skid plate, if equipped. (Refer to 13 -
FRAMES & BUMPERS/FRAME/TRANSFER CASE
SKID PLATE - REMOVAL)
(3) Position drain oil container under transfer
case.
(4) Remove transfer case drain plug and drain
lubricant into container.
(5) Disconnect vent hose and transfer case position
sensor connector.
(6) Disconnect shift rod from grommet in transfer
case shift lever, or from floor shift arm whichever
provides easy access. Use channel lock style pliers to
press rod out of lever grommet.
(7) Support transmission with jack stand.
(8) Mark front and rear propeller shafts for assem-
bly reference.(9) Remove front and rear propeller shafts. (Refer
to 3 - DIFFERENTIAL & DRIVELINE/PROPELLER
SHAFT/PROPELLER SHAFT - REMOVAL)
(10) Support transfer case with suitable jack.
Secure transfer case to jack with safety chains.
(11) Remove nuts attaching transfer case to trans-
mission.
(12) Move transfer case assembly rearward until
free of transmission output shaft.
(13) Lower jack and move 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.
DRTRANSFER CASE - NV241 GENII 21 - 417
TRANSFER CASE - NV241 GENII (Continued)

(2) Loosen rear case with pry tool to break sealer
bead. Insert tool in slot at each end of case (Fig. 12).
(3) Unseat rear case from alignment dowels.
(4) Remove rear case and oil pump assembly from
front case (Fig. 13).
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 bearing
inner 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.FRONT OUTPUT SHAFT AND DRIVE CHAIN
(1) Remove shift rail cup and spring (Fig. 14).
(2) Remove front sprocket retaining ring (Fig. 15).
Fig. 12 Loosen Case Halves
1 - REAR CASE
2 - FRONT CASE
3 - PRY SLOTS
Fig. 13 Remove Rear Case
1 - REAR CASE
2 - FRONT CASE
Fig. 14 Shift Rail Cup And Spring Removal
1 - SHIFT RAIL
2 - SPRING
3 - CUP
Fig. 15 Removing Front Sprocket Retaining Ring
1 - FRONT SPROCKET
2 - RETAINING RING
3 - FRONT OUTPUT SHAFT
21 - 420 TRANSFER CASE - NV241 GENIIDR
TRANSFER CASE - NV241 GENII (Continued)

(3) Pull mainshaft, front sprocket and chain out-
ward about 25.4 mm (1-inch) simultaneously (Fig.
16).
(4) Remove chain from mainshaft drive sprocket
and remove front sprocket and chain as assembly.
SHIFT FORKS AND MAINSHAFT
(1) Remove the transfer case position sensor (Fig.
17).(2) Loosen detent plug.
(3) Remove detent plug, spring, and plunger (Fig.
18). Note that the plug has an O-ring seal. Remove
and discard this seal.
(4) Remove the front output shaft snap-ring (Fig.
19).
Fig. 16 Remove Front Sprocket and Drive Chain
1 - FRONT DRIVE SPROCKET
2 - DRIVE CHAIN
3 - MAINSHAFT
Fig. 17 Remove Position Sensor
1 - FRONT CASE
2 - POSITION SENSOR
Fig. 18 Remove Detent Plug, Spring, and Plunger
1 - FRONT CASE
2 - DETENT PLUG
3 - DETENT SPRING
4 - DETENT PLUNGER
Fig. 19 Remove Front Output Shaft Snap-ring
1 - FRONT OUTPUT SHAFT
2 - SNAP-RING
DRTRANSFER CASE - NV241 GENII 21 - 421
TRANSFER CASE - NV241 GENII (Continued)

(10) Remove the shift sector support (Fig. 24).
(11) Remove shift sector (Fig. 25).MAINSHAFT
(1) Remove the drive sprocket retaining ring (Fig.
26) from the output shaft.
(2) Remove the drive sprocket thrust washer (Fig.
27) from the output shaft.
Fig. 24 Remove Sector Support
1 - SECTOR SUPPORT
2 - FRONT CASE
3 - SECTOR SHAFT
Fig. 25 Remove Shift Sector
1 - SHIFT SECTOR
Fig. 26 Remove The Drive Sprocket Retaining Ring
1 - OUTPUT SHAFT
2 - RETAINING RING
3 - DRIVE SPROCKET
Fig. 27 Remove Drive Sprocket Thrust Washer
1 - OUTPUT SHAFT
2 - THRUST WASHER
3 - DRIVE SPROCKET
DRTRANSFER CASE - NV241 GENII 21 - 423
TRANSFER CASE - NV241 GENII (Continued)