1993 DODGE TRUCK Service Repair Manual

21 - 344
NP205
TRANSFER
CASE

• (a) Raise vehicle and disconnect both propeller
shafts at the transfer case.
(b) Position supports under the transmission.
(c) Remove the bolts/nuts attaching the transfer
case adapter to the crossmember and transmission. (d) Support the transfer case with a transmission
jack and slide the transfer case and adapter clear of the transmission output shaft.
(e) Have helper start engine and shift transmis­
sion into gear. If transmission output shaft rotates,
problem is with transfer case. If transmission shaft
does not rotate, problem is with transmission or re­ lated component.

SHIFT
LINKAGE
ADJUSTMENT
(1) Shift transfer case into neutral.

(2)
Remove screws attaching shift lever boot and
seal to floor pan (Fig. 2). (3) Slide shift lever boot and seal upward for vi­
sual access to shift gate. Verify that lever is in Neu­
tral position. (4) Loosen bolts" attaching shift lever bracket to
adapter (Fig. 3).
Fig.
2 Shift
Lever
Boot
And
Seal

Fig.
3 NP205 Shift
Linkage

•

NP20I
TRANSFER CASE
21 - 34i (5) Verify that transfer case range lever is in Neu­

tral.
(6) Move shift lever bracket forward and retighten
bracket bolts (Fig. 3). Shift rod should not bind in shift lever and range lever. Rod should be slip-fit
both levers. (7) Shift transfer case into 4H range. Shift rod
should now be tension-fit in each lever. Shift lever
should be in 4H detent in gate and range lever should be fully into 4H position.
(8) Shift transfer case into 2H and 4L ranges to
verify correct adjustment.

SPEEDOMETER SERVICE
The speedometer driven gear, adapter and vehicle
speed sensor can be serviced with the transfer case in
the vehicle.
SPEEDOMETER COMPONENT REMOVAL/
INSTALLATION (FIG. 4) (1) Shift transfer case into Neutral.
(2) Raise vehicle.
(3) Disconnect wires at vehicle speed sensor.
(4) Loosen and disconnect coupling nut that at­
taches speed sensor to adapter. Then loosen and dis­ connect coupling nut attaching adapter to driven
gear.
(5) Remove vehicle speed sensor and speedometer
adapter. (6) Loosen and remove speedometer driven gear.
(7) Lubricate driven gear with engine or gear oil
and install gear in transfer case. Tighten gear to 11
N*m (100 in. lbs.) torque. (8) Install adapter and speed sensor. Tighten cou­
pling nuts to 17 N»m (150 in. lbs.) torque. (9) Connect wires to speed sensor.
(10) Lower vehicle.

TRANSFER CASE
REMOVAL
(1) Raise vehicle.
(2) Remove drain plug and drain transfer case lu­
bricant. (3) Disconnect vehicle speed sensor wires.
(4) Mark front/rear propeller shafts and yokes for
installation reference. (5) Disconnect and remove propeller shafts. Or dis­
connect shafts at transfer case yokes. Then move shafts aside for working clearance and secure them
to frame rails with wire. (6) Disconnect transfer case shift lever from range
lever on transfer case. (7) Support transfer case with transmission jack.
Secure transfer case to jack with safety chains. (8) Remove nuts attaching transfer case to trans­
mission adapter. (9) Slide transfer case rearward until it is clear of
transmission output shaft.
DISTANCE

SENSOR
ADAPTER
DRIVEN
GEAR
J9021-151

Fig.
4 Speedometer Components.
(10) Lower jack and move transfer case from under
vehicle.
(11) Remove old gasket material from transmission
adapter.

TRANSFER CASE
INSTALLATION
(1) Apply Mopar perfect seal, silicone sealer, or
Permatex No. 2 sealer to both sides of transfer case-
to-transmission gasket. Then position gasket on
transmission. (2) Align and seat transfer case on transmission.
Be sure transfer case input gear splines are aligned
with transmission output shaft. Align splines by ro­
tating transfer case rear output shaft yoke if neces­ sary. Do not install any transfer case attaching
nuts until the transfer case is completely seated against the transmission. (3) Install and tighten transfer case attaching nuts
to 47 N*m (35 ft. lbs.). (4) Install rear crossmember.
(5) Remove jack stand from under transmission.
(6) Align and connect propeller shafts.
(7) Connect vehicle speed sensor wires.
(8) Connect transfer case shift lever to range lever.
Tighten lever locknut to 10 N»m (90 in. lbs.). (9) Fill transfer case with recommended lubricant.
(10) Install transfer case fill plug.
(11) Install skid plate and skid plate crossmember.
(12) Lower vehicle.

TRANSFER CASE DISASSEMBLY
(FIG.
S) REAR RETAINER AND OUTPUT SHAFT
REMOVAL/DISASSEMBL
Y
(1) Loosen rear yoke nut until only 2-3 threads are
holding nut on shaft. (2) Remove bolts attaching rear bearing retainer to

case.

(3) Pull yoke rearward to start rear output shaft
out of clutch. (4) Remove rear yoke nut, washer, seal washer and
yoke.

NP205
TRANSFER CASE
21 - 347
LEGEND FOR NP205 TRANSFER CASE

YOKE NUT
®

WASHER
©
SEAL
WASHER
©
REAR
YOKE
©

OIL SEAL
©

REAR
SEAL RETAINER
©

GASKET
©
SNAP
RING
©

REAR
OUTPUT
SHAFT BEARING
©

SPEEDOMETER
GEAR
®
BEARING RETAINER
-
REAR
©

VENT TUBE CONNECTOR
©

GASKET
©

REAR
OUTPUT
SHAFT SUPPORT
©

BEARING
©

LOW GEAR RETAINING RING
THRUST WASHER
(3/16"
THICK)
©
THRUST WASHER
(1/16"
THICK)
©
LOW GEAR ROLLER BEARINGS
[64)
©

BEARING SPACER
©

LOW GEAR
-
REAR SHAFT
©

THRUST WASHER
(1/16"
THICK)
®

REAR
OUTPUT
SHAFT
©

THRUST WASHER PIN
©

SLIDING CLUTCH

PILOT
BEARING ROLLERS
(15) ©

PILOT
BEARING THRUST
©

WASHER
©
LOCK RING
©

INPUT
GEAR
©

IDLER SHAFT COVER
©
GASKET
IDLER SHAFT
IDLER GEAR BEARINGS
BEARING
RACES

BEARING SPACER
IDLER GEAR
IDLER GEAR BEARING SHIMS
WASHER IDLER SHAFT LOCK NUT
THRUST WASHER
PIN
FRONT
OUTPUT
SHAFT
SLIDING CLUTCH

HIGH
GEAR
THRUST WASHER FRONT
OUTPUT
SHAFT FRONT
BEARING
BEARING SNAP RING
FRONT
OUTPUT
SHAFT REAR
BEARING
BEARING RETAINER
-
FRONT
GASKET
RETAINING RING
THRUST WASHER
(3/16"
THICK)
LOW GEAR
-
FRONT SHAFT
LOW GEAR ROLLER BEARINGS
(S3.
iRING
SPACER
FLANGE
OIL SEAL FRONT SEAL RETAINER
GASKET DRAIN PLUG ©
©
©
©
©
©
® ©
©
®
®
©
©
©
©
©
©^
© ©
®
©
©
CASE
MAGNET AND CLIP

FILL
PLUG
PTO COVER AND GASKET
GEAR
CASE

SHIFT RAIL DETENT BALLS
AND SPRINGS
4WD INDICATOR
LIGHT
SWITCH AND GASKET
SHIFT FORK AND RAIL
-
REAR
WHEEL
INTERLOCK PINS
(2)

FORK-TO-RAIL LOCK PIN
SHIFT RAIL OIL
SEALS

SHIFT RAIL
LINK
RETAINING CLIP
(21

LINK-TO-RAIL
RETAINING
PIN

3
HIFT FORK
AND RAIL
-

FRONT WHEEL INTERLOCK HOLE PLUGS
(4)

FRONT
OUTPUT
SHAFT
BEARING
BEARING SNAP RING

INPUT
SHAFT SNAP RING
ADAPTER OIL SEAL
(2)
GASKET

TRANSFER
CASE
ADAPTER ADAPTER SLEEVE
SLEEVE
RETAINING RING
GASKET

TRANSMISSION
ADAPTER

J9021-149

(5)
Remove rear retainer, rear output shaft and
gears as assembly. (6) Remove rear seal retainer from bearing re­
tainer.
(7) Remove snap ring. (8) Remove rear bearing retainer.

(9)
Remove rear bearing, speedometer gear, shaft
support bearings, thrust washer pin and low gear
from rear output shaft (Fig. 5).
(10) Remove lock ring, thrust washer and pilot
bearing rollers from rear output shaft (Fig. 5).
FRONT OUTPUT SHAFT RETAINER REMOVAL (1) Remove front yoke nut, washer and flange (Fig.

5).

(2) Remove front seal retainer and gasket.
(3) Remove PTO cover and gasket.

(4)
Remove detent plug and 4WD indicator light
switch from case (Fig. 5).

(5)
Remove shift rail detent springs and balls (Fig.

5).
Use pencil magnet to remove these components. (6) Remove bolts attaching front bearing retainer
to case. (7) Tap front output shaft with plastic mallet to
loosen it. Then remove shaft, retainer and gears (Fig.
6).
(8) Remove shaft snap ring (Fig. 7).
(9)
Remove thrust washer, gear, bearings and
spacer.

HAMMER

FRONT

OUTPUT
SHAFT
REAR
BEARING

RETAINER
RH320

Fig. 6
Removing/Installing
Front Output Shaft
SHIFT RAIL, IDLER GEAR, INPUT GEAR AND
FRONT SHAFT REMOVAL (1) Remove adapter and gasket. (2) Remove idler shaft nut and washer.
(3) Remove idler shaft cover plate and gasket.

21
- 348 NP20S TRANSFER CASE
Fig. 7 Removing/installing Front Shaft Snap Ring (4) Remove cup plugs at top of case for access to shift
fork lock pins. Use small punch to remove plugs.

(5)
Place shift rails in Neutral position.
(6) Remove lock, pins from shift forks with long
handle easy-out tool (Fig. 8).
Fig. 8 Removing/Installing Shift Fork Lock Pins
(7) Remove pins attaching shift rail link and re­
move link.
(8) Remove shift forks and sliding clutches.
(9) Remove snap ring, thrust washer and bearing
from front shaft.
(10) Remove front shaft and high gear.
(11) Remove input gear, bearing, seals and washer.
(12) Loosen and remove idler shaft with plastic
mallet (Fig. 9).
(13) Tilt case, roll idler gear toward front shaft open­
ing in case and remove gear through this opening.
(14) Remove and retain idler shaft shims. Tie
shims together to avoid losing them.
(15) Remove bearing cups and bearings from idler
gear.
4

Fig. 9 Idler Shaft
Removal
(16) Remove interlock pins from inside case. Re­
move pins through PTO cover opening.
(17) If front output shaft rear bearing must be re­
placed, replace the bearing and retainer as an assem­
bly only.
TRANSFER CASE ASSEMBLY Lubricate the transfer case gears and shafts with
gear oil during assembly. Use petroleum jelly to pre-
lubricate and hold bearings in place during installa­
tion. Use new gaskets and seals throughout. Do not re­
use these components. Replace snap rings if distorted
or damaged and use new yoke locknuts to secure the
yoke and flange. (1) Install bearing cups in idler gear with shop
press (Fig. 10).
(2) Assemble idler gear, gear bearing cones, bear­
ing spacer and shims on Shaft Tool DD1272 (Fig. 10).
(3) Check gear end play (Fig. 10). End play should
be 0.000 to 0.05 mm (0.000 to 0.002 in.). Add or re­
move shims as needed to adjust end play.
(4) Press shift rail seals into case. Seals are wiper-
type and should be installed with seal lip facing out­
ward.
(5) Install assembled idler gear assembly and shaft
tool in case. Insert assembly through front shaft

bore,
large end first. Tilt case at 45° angle to ease
bearing installation at boss (Fig. 11).
(6) Install idler shaft. Insert shaft from large bore
side and tap shaft into gear and bearings with dead-
blow hammer. Remove shaft alignment tool as idler shaft pushes it out of gear and case. (7) Install idler shaft washer and new locknut.
Check end play and free rotation. Tighten locknut to
203 N-m (150 ft. lbs.). (8) Install front bearing and snap ring on input
gear. (9) Assemble front output shaft. Install gears, slid­
ing clutch, bearings, thrust washer pin, thrust wash­

ers,
snap ring and retainer on front output shaft.

1
•
NP241
TRANSFER CASE
21 - 349

Fig.
11 Installing Idler Gear (10) Install interlock pins through large case bore
or PTO opening,
(11) Install input gear in case. Then install sliding
clutch on input gear and position shift fork in clutch.
(12) Install rear wheel shift rail into case (from

back),
with slotted end first and detent notches fac­ ing up (Fig. 8). Then push rail through shift fork and
into opposite end of case.
(13) Install front output shaft in case.
(14) Install front wheel shift fork in sliding clutch
on front shaft. Then install front wheel shift rail into
case and through shift fork.
(15) Secure shift forks to shift rails with new lock

pins.
Install pins through small bores at top of case.
(16) Install front output shaft bearing retainers.
Be sure oil drain slot in bearing retainer is aligned with drain hole in case before tightening

bolts.
Use new gaskets and apply sealer to bolt
threads before installation. Use extra gasket on re­
tainers if necessary. (17) Install flange on front shaft. Install seal washer
on shaft and install flange locknut finger tight. (18) Install washer, seals gasket and adapter on
input shaft (Fig. 5). (19) Install shift link and link retaining pins, clips.
(20) Assemble rear output shaft. Install gears,
bearings and spacers (Fig. 5).
(21) Install new snap ring. Tap ring to seat it and
check end play. End play should be 0.05 to 0.68 mm (0.002 to 0.027 in.).
(22) Install pilot bearing rollers in rear output
shaft. Use as much petroleum jelly as needed to hold
bearing rollers in place.
(23) Install pilot bearing thrust washer and new
snap ring. (24) Install retainer on rear output shaft install
speedometer gear and spacer, install bearing (Fig. 12).
Fig.
12
Assembling
Rear Retainer And Output Shaft
(25) Install retainer and shaft assembly. Be sure
oil drain slot in retainer is aligned with drain
hole in case. Use one or two retainer gaskets de­
pending on clearance. Tighten retainer bolts to 54
N»m (40 ft. lbs.).
(26) Install seals in front and rear seal retainers.
Position gaskets on case and install retainers over shafts and against case. Tighten bolts to 54 Nnn (40
ft. lbs.). (27) Install yoke and flange. Tighten yoke and
flange nuts to 176 N» (130 ft. lbs.).
(28) Install detent balls, springs, plugs, cup plugs
and 4WD indicator light switch.
(29) Install drain plug.
(30) Fill transfer case to bottom edge of fill plug
hole with recommended lubricant.
(31) Install fill plug.

21 - 350 NP241
TRANSFER CASE

• NP241 TRANSFER CASE

INDEl

page

Checking
Fluid
Level
351

Component Cleaning
and
Inspection
359
Fluid
Drain/Refill
351

General
Information
350

Recommended
Lubricant
.................. 350

Service
Diagnosis
....................... 350

Shift
Linkage
Adjustment
354

Speedometer Adapter/Distance
Sensor
Service
. 352
page

Speedometer Gear, Shaft
Seal,
Bearing
and
Retainer
Service
352

Transfer
Case
Assembly
.................. 361

Transfer
Case
Bearing Replacement
......... 360
Transfer
Case
Disassembly
................ 356

Transfer
Case
Identification ................ 350

Transfer
Case
Installation
................. 356

Transfer
Case
Removal
356

GENERAL
INFORMATION
The NP241 is a part-time transfer case with a low-
range gear system. It has three operating ranges
plus a Neutral position. The low range system pro­ vides a gear reduction ratio for increased low speed
torque capability. NP241 operating ranges are: 2-high, 4-high and 4-low. The NP241 has an aluminum, two-piece gear case.
Drive sprockets and an interconnecting drive chain are used to transmit engine torque to the propeller

shafts.
Four-wheel high and low ranges are undifferenti­
ated. The transfer case is not designed for continuous
operation in 4WD range on hard or paved surfaces.
Four wheel drive ranges are recommended for off
road operation, or on snow covered or similar low
traction surfaces. A front axle disconnect system is used to achieve
two-wheel drive mode. The axle disconnect vacuum motor is actuated by a vacuum switch on the transfer

case.
The switch is operated by the transfer case
range rod. Two-wheel drive range is used for on road, high­
way operation. The four-wheel drive ranges are for off road operation or when the vehicle is driven on
paved road surfaces covered by snow, ice or similar low traction elements.

TRANSFER CASE
IDENTIFICATION
An identification tag (Fig, 1) is attached to the rear
case of each NP241 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. For example, a serial number of 9-10-92 would represent September 10, 1992. Transfer case operating ranges are selected with a
floor-mounted shift lever. The shift lever is connected
to the transfer case range lever by an adjustable linkage rod (Fig. 2). A straight line shift pattern is
used. Range positions are marked on the gearshift le­
ver knob.
Fig.
1 NP 241 Transfer
Case

A synchronizer assembly in the transfer case al­
lows the unit to be shifted between 2H and 4H
ranges while the vehicle is in motion. The vehicle should be stopped before shifting into 4L range.

RECOMMENDED
LUBRICANT
Recommended lubricant for the NP241 is Mopar
ATF Plus, type 7176, or Dexron II™ automatic trans­
mission fluid. Use either fluid for topping off the
level, or refilling after service, or normal fluid
changes. Do not use anti-friction additives or similar prod­
ucts in the NP241 transfer case. Use the recom­
mended lubricant only. NP241 transfer case lubricant should be changed
at the intervals specified in the Maintenance Sched­
ule or after service repairs.

SERVICE
DIAGNOSIS
Before attempting to repair 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

•
NP241 TRANSFER CASE
21 - 351
SERVICE
DIAGNOSIS

Condition
Possible
Cause
Correction

TRANSFER
CASE
DIFFICULT
TO
SHIR

OR
WILL
NOT
SHIFT
INTO
DESIRED

RANGE

TRANSFER
CASE
NOISY
IN ALL

DRIVE
MODES

NOISY
IN-OR

JUMPS
OUT
OF
FOUR-WHEEL-DRIVE

LOW
RANGE

LUBRICANT

LEAKING
FROM

OUTPUT
SHAFT
SEALS
OR
FROM

VENT

ABNORMAL

TIRE
WEAR
(a)
Vehicle speed
too
great
to permit

shifting.

(b)
If
vehicle was operated
for
extended
period
in 4H
mode
on dry
paved

surface,
driveline
torque
load
may

cause
difficulty.
(c) Transfer
case
external
shift linkage
binding.

(d) Insufficient
or
incorrect lubricant.
(e) Internal components binding, worn
or
damaged.

(a) Insufficient
or
incorrect lubricant.
(a) Transfer
case
not
completely engaged in
4L
position.
(b) Shift linkage
loose
or
binding.
(c)
Range
fork cracked, inserts worn,
or
fork is binding
on
shift rail.
(d)
Annulus
gear
or
lockplate work
or
damaged.

(a) Transfer
case
overfilled.
(b) Vent
closed
or
restricted.
(c) Output shaft
seals
damaged
or
installed correctly.
(a) Extended operation
on dry
hard
surface
(paved) roads
in 4H
range. (a)
Stop
vehicle and shift into desired

range.
Or
reduce speed
to 3-4
km/h (2-3 mph) before attempting
to
shift.
(b)
Stop
vehicle, shift
transmission
to
neutral, shift transfer
case
to 2H
mode

and
operate vehicle on
2H on dry
paved
surface.
(c) Lubricate, repair
or
replace linkage,
or
tighten loosen components as necessary.
(d) Drain and
refill to
edge
of fill
hole
with
MOPAR
ATF
PLUS
(Type
7176) or
DEXRON
II
Automatic
Transmission
Fluid.

(e)
Disassemble
unit and replace worn
or
damaged
components
as necessary.
(a) Drain and
refill to
edge
of fill
hole
with
MOPAR
ATF
PLUS
(Type
7176) or
DEXRON
II
Automatic
Transmission

Fluid.
Check
for
leaks and repair
if

necessary.
If
unit
is
still
noisy
after

drain
and
refill,
disassembly
and
inspection
may be
required
to
locate

source
of
noise.

(a)
Stop
vehicle, shift transfer
case
to
Neutral, then shift back into
4L
position.
(b) Tighten, lubricate,
or
repair linkage
as
necessary.

(c)
Disassemble
unit and repair
as
necessary

(d)
Disassemble
unit and repair
as
necessary

(a) Drain
to
correct level.
(b) Clear
or
replace vent
if
necessary.

(c) Replace
seals.
Be sure seal
lip
faces interior
of
case
when installed.
Also
be

sure
yoke seal surfaces
are not
scored

or
nicked. Remove
scores
and nicks
with

fine sandpaper
or
replace yoke(s)
if
necessary.

(a) Operate
in 2H on
hard surface (paved)
roads.

and operating properly, refer to the Service Diagno­
sis chart for further information.

CHECKING FLUID LEVEL
Correct fluid level for the NP241 transfer case is to
the bottom edge of the fill plug hole. A correct method of checking fluid level is im­
portant. An accurate check requires that the
transfer case be level. If fluid level is checked with the vehicle parked on
the shop floor, be sure the floor area used is level. If J9021-152
fluid level is checked with the vehicle raised, use ei­
ther a swivel arm or drive-on type hoist to be sure
the vehicle is level.

FLUID DRAIN/REFILL
(1) Raise vehicle.
(2) Position drain pan under transfer case.

(3)
Remove drain and fill plugs and drain lubri­
cant completely. (4) Install drain plug. Tighten plug to 54 N»m (40
ft. lbs.). (5) Remove drain pan.