1998 DODGE RAM 1500 Transfer case

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)

SHIFT LEVER AND FRONT OUTPUT SHAFT SEAL
(1) Shift transfer case into NEUTRAL.
(2) Remove nut that retains the shift lever to sec-
tor shaft. Then remove shift lever from shaft (Fig. 3).
(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 ears away from the
transfer case.
(6) Using a suitable pry tool (Fig. 7), remove the
slinger from the output shaft using care not to dam-
age the shaft.
(7) Using a screw and a slide hammer, remove the
front output shaft seal.
Fig. 3 Remove Range Lever Nut
1 - RANGE LEVER
Fig. 4 Remove Boot Clamp
1 - SEAL BOOT
2 - BOOT CLAMP
Fig. 5 Remove Seal Boot
1 - SEAL BOOT
2 - SEAL SLINGER
Fig. 6 Bend Slinger Ears
1 - SLINGER
2 - BEND UPWARD
Fig. 7 Remove Slinger From Shaft
1 - SLINGER
2-PRYTOOL
21 - 418 TRANSFER CASE - NV241 GENIIDR
TRANSFER CASE - NV241 GENII (Continued)

REAR EXTENSION
(1) Remove rear extension bolts (Fig. 8).
(2) Remove rear extension housing (Fig. 9). 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. 10).
OIL PUMP AND REAR CASE
(1) Remove rear case-to-front case bolts (Fig. 11).
Fig. 8 Remove Rear Extension Bolts
1 - EXTENSION HOUSING
2 - TRANSFER CASE
Fig. 9 Remove Rear Extension
1 - EXTENSION HOUSING
2 - TRANSFER CASE
3 - PRY SLOT
Fig. 10 Remove Output Shaft Retaining Ring
1 - REAR OUTPUT SHAFT
2 - OUTPUT SHAFT BEARING
3 - RETAINING RING
4 - TRANSFER CASE
Fig. 11 Remove Case Bolts
1 - REAR CASE
2 - FRONT CASE
3 - BOLT
DRTRANSFER CASE - NV241 GENII 21 - 419
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)

(5) Remove front output shaft from bearing in case
(Fig. 20).
(6) Pull mainshaft assembly out of input gear,
mode sleeve, and case (Fig. 21).(7) Remove mode fork, mode sleeve, and shift rail
as assembly (Fig. 22). Note which way the sleeve fits
in the fork (long side of sleeve goes to front).
(8) Remove range fork retaining ring.
(9) Remove range fork and hub as an assembly
(Fig. 23). Note fork position for installation reference.
Fig. 23 Range Fork And Hub Removal
1 - RANGE HUB
2 - RANGE FORK
Fig. 20 Remove Front Output Shaft
1 - FRONT CASE
2 - FRONT OUTPUT SHAFT
Fig. 21 Remove Mainshaft
1 - FRONT CASE
2 - MAINSHAFT
Fig. 22 Remove Mode Fork and Shift Rail
1 - MODE FORK
2 - SHIFT RAIL
3 - MODE SLEEVE
21 - 422 TRANSFER CASE - NV241 GENIIDR
TRANSFER CASE - NV241 GENII (Continued)