nv 247 JEEP GRAND CHEROKEE 2002 WJ / 2.G User Guide

holding the Belleville spring into the low/reverse
clutch retainer.
(10) Remove the low/reverse clutch Belleville
spring and piston from the low/reverse clutch
retainer. Use 20 psi of air pressure to remove the pis-
ton if necessary.
CLEANING
Clean the overrunning clutch assembly, clutch cam,
and low-reverse clutch retainer. Dry them with com-
pressed air after cleaning.
INSPECTION
Inspect condition of each clutch part after cleaning.
Replace the overrunning clutch roller and spring
assembly if any rollers or springs are worn or dam-
aged, or if the roller cage is distorted, or damaged.
Replace the cam if worn, cracked or damaged.
Replace the low-reverse clutch retainer if the
clutch race, roller surface or inside diameter is
scored, worn or damaged.
ASSEMBLY
(1) Check the bleed orifice to ensure that it is not
plugged or restricted.
(2) Install a new seal on the low/reverse piston.
Lubricate the seal with MopartATF +4, type 9602,
prior to installation.
(3) Install the low/reverse piston into the low/re-
verse clutch retainer.
(4) Position the low/reverse piston Belleville spring
on the low/reverse piston.
(5) Using Spring Compressor 8285 and a suitable
shop press (Fig. 86), compress the low/reverse piston
Belleville spring and install the split retaining ring
to hold the Belleville spring into the low/reverse
clutch retainer.
(6) Install the lower overrunning clutch snap-ring
(Fig. 85).
(7) Assemble the inner and outer races of the over-
running clutch (Fig. 85).
(8) Position the overrunning clutch spacer on the
overrunning clutch.
(9) Install the upper overrunning clutch snap-ring
(Fig. 85).
(10) Assemble and install the low/reverse clutch
pack into the low/reverse clutch retainer (Fig. 84).
(11) Install the low/reverse reaction plate into the
low/reverse clutch retainer (Fig. 84). The reaction
plate is directional and must be installed with the
flat side down.
(12) Install the low/reverse clutch pack snap-ring
(Fig. 84). The snap-ring is selectable and should be
chosen to give the correct clutch pack clearance.
(13) Measure the low/reverse clutch pack clearance
and adjust as necessary. The correct clutch clearance
is 1.00-1.74 mm (0.039-0.075 in.).
(14) Install the overrunning clutch into the low/re-
verse clutch retainer making sure that the index
splines are aligned with the retainer.
(15) Install the overrunning clutch inner snap-
ring.
Fig. 85 Overrunning Clutch
1 - SNAP-RING
2 - OUTER RACE
3 - OVERRUNNING CLUTCH
4 - SPACER
Fig. 86 Compress Low/Reverse Belleville Spring
Using Tool 8285
1 - PRESS
2 - TOOL 8285
3 - BELLEVILLE SPRING
WJAUTOMATIC TRANSMISSION - 545RFE 21 - 247
LOW/REVERSE CLUTCH (Continued)

TRANSFER CASE - NV247
TABLE OF CONTENTS
page page
TRANSFER CASE - NV247
DESCRIPTION........................315
OPERATION..........................316
DIAGNOSIS AND TESTING - TRANSFER
CASE - NV247.......................316
REMOVAL............................317
DISASSEMBLY........................317
CLEANING...........................324
INSPECTION.........................324
ASSEMBLY...........................326
INSTALLATION........................335
SPECIFICATIONS
TRANSFER CASE - NV247.............336
SPECIAL TOOLS
TRANSFER CASE - NV247.............337FLUID
STANDARD PROCEDURE - FLUID DRAIN/
REFILL............................338
FRONT OUTPUT SHAFT SEAL
REMOVAL............................338
INSTALLATION........................338
REAR RETAINER BUSHING AND SEAL
REMOVAL............................339
INSTALLATION........................339
SHIFT CABLE
REMOVAL............................340
INSTALLATION........................340
TRANSFER CASE - NV247
DESCRIPTION
The NV247 (Fig. 1) is an on-demand 4-wheel drive
transfer case with two operating ranges and a neu-
tral position. Operating ranges are 4-high and 4-low.
The 4-low range is used for extra pulling power in
off-road situations.
TRANSFER CASE IDENTIFICATION
A circular I.D. tag is attached to the rear case of
each NV247 transfer case (Fig. 2). The tag indicates
the following information:
²Model number
²Serial number
²Assembly number
²Gear ratio
²Location of manufacture
The transfer case serial number also represents
the date of build.
Fig. 1 NV247 Transfer Case
Fig. 2 Transfer Case I.D. Tag
1 - FILL PLUG
2 - I.D. TAG
3 - DRAIN PLUG
WJTRANSFER CASE - NV247 21 - 315

OPERATION
Under normal driving conditions, the system oper-
ates conventionally, and the majority of available
torque is applied to the rear wheels. However, when
front-to-rear wheel speed variations exist, the pro-
gressive differential transfers torque to the axle with
the better traction, thus minimizing wheel spin and
maximizing control.
The key to this design is a progressive coupling
(Fig. 3), which is supplied with pressurized oil by a
gerotor style pump. The pump rotor and case are
driven by the front and rear driveshafts respectively,
and deliver pressurized oil flow to the coupling in
proportion to their speed difference. The progressive
coupling contains a multi-disc clutch pack that is
alternately splined to the front and rear driveshafts,
and controls torque variation between the front and
rear driveshafts as dictated by the pump.
A set of orifices and valves control the speed-differ-
ential starting point and rate of torque transfer rise
in the clutch. This allows the system to disregard the
normal speed differences between axles that result
from variations in front-to-rear loading and typical
cornering.
Transfer case operating ranges are selected with a
floor mounted shift lever. The shift lever is connectedto the transfer case range lever by an adjustable
cable. Range positions are marked on the shifter
bezel plate.
DIAGNOSIS AND TESTING - TRANSFER CASE - NV247
CONDITION POSSIBLE CAUSE CORRECTION
TRANSFER CASE DIFFICULT TO
SHIFT OR WILL NOT SHIFT INTO
DESIRED RANGE1. Vehicle speed too great to permit
shifting1. Reduce speed to 3-4 km/h (2-3
mph) before attempting to shift
2. Transfer case external shift cable
binding2. Lubricate, repair or replace cable,
or thighten loose components as
necessary
3. Insufficient or incorrect lubricant 3. Drain and refill to edge of fill hole
with correct lubricant
4. Internal components binding,
worn, or damaged4. Disassemble unit and replace
worn or damaged components as
necessary
TRANSFER CASE NOISY IN ALL
MODES1. Insufficient or incorrect lubricant 1. Drain and refill to edge of fill hole
with correct lubricant.If unit is still
noisy after drain and refill,
disassembly and inspection may
be required to locate source of
noise
Fig. 3 Progressive Coupling
21 - 316 TRANSFER CASE - NV247WJ
TRANSFER CASE - NV247 (Continued)

CONDITION POSSIBLE CAUSE CORRECTION
NOISY INÐOR JUMPS OUT OF
4WD LOW RANGE1. Transfer case not completely
engaged in 4WD LOW (possibly
from shift to 4L while rolling)1. Stop vehicle, shift transfer case
to neutral, then shift back to 4WD
LOW
2. Shift linkage loose, binding, or is
misadjusted2. Tighten, lubricate, or repair
linkage as necessary. Adjust linkage
if necessary
3. Range fork cracked, inserts
worn, or fork is binding on shift rail3. Disassemble unit and repair as
necessary
4. Annulus gear or lockplate worn
or damaged4. Disassemble unit and repair as
necessary
LUBRICANT LEAKING FROM
OUTPUT SHAFT SEALS OR FROM
VENT1. Transfer case over filled 1. Drain to correct level
2. Vent closed or restricted 2. Clear or replace vent if necessary
3. Output shaft seals damaged or
installed correctly3. 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.
REMOVAL
(1) Shift transfer case into NEUTRAL.
(2) Raise vehicle.
(3) Remove transfer case drain plug and drain
transfer case lubricant.
(4) Mark front and rear propeller shaft yokes for
alignment reference.
(5) Support transmission with jack stand.
(6) Remove rear crossmember and skid plate, if
equipped (Fig. 4).
(7) Disconnect front propeller shaft from transfer
case at companion flange. Remove rear propeller
shaft from vehicle. (Refer to 3 - DIFFERENTIAL &
DRIVELINE/PROPELLER SHAFT/PROPELLER
SHAFT - REMOVAL)
CAUTION: Do not allow propshafts to hang at
attached end. Damage to joint can result.
(8) Disconnect transfer case cable from range
lever.
(9) Disconnect transfer case vent hose (Fig. 5).
(10) Support transfer case with transmission jack.
(11) Secure transfer case to jack with chains.
(12) Remove nuts attaching transfer case to trans-
mission.
(13) Pull transfer case and jack rearward to disen-
gage transfer case (Fig. 5).
(14) Remove transfer case from under vehicle.
DISASSEMBLY
Position transfer case on shallow drain pan.
Remove drain plug and drain lubricant remaining in
case.
Fig. 4 Crossmember Removal
1 - CROSSMEMBER
2 - REAR TRANSMISSION MOUNT
WJTRANSFER CASE - NV247 21 - 317
TRANSFER CASE - NV247 (Continued)

REAR RETAINER AND OIL PUMP
(1) Remove rear retainer bolts (Fig. 6).
(2) Remove rear bearing locating ring access plug
(Fig. 7).(3) Loosen rear retainer with pry tool to break
sealer bead. Pry only against retainer boss as shown
(Fig. 8).
(4) Remove rear retainer as follows:
(a) Spread rear bearing locating ring with snap
ring pliers (Fig. 9).
(b) Then slide retainer off mainshaft and rear
bearing (Fig. 10).
Fig. 5 Transfer Case Mounting
1 - NV247 TRANSFER CASE
Fig. 6 Rear Retainer Bolt Removal
1 - REAR RETAINER
Fig. 7 Remove Rubber Access Plug
1 - PLUG
Fig. 8 Loosening Rear Retainer
1 - RETAINER BOSS
2-PRYTOOL
3 - SEALER BEAD
4 - REAR RETAINER
21 - 318 TRANSFER CASE - NV247WJ
TRANSFER CASE - NV247 (Continued)

(5) Remove rear bearing snap-ring.
(6) Remove rear bearing. Note position of bearing
locating ring groove for assembly reference.
(7) Disengage oil pickup tube from oil pump and
remove oil pump assembly (Fig. 11).
(8) Remove pick-up tube o-ring from oil pump (Fig.
12), if necessary. Do not disassemble the oil pump, it
is not serviceable.
COMPANION FLANGE AND RANGE LEVER
(1) Remove front companion flange nut as follows:
(a) Move range lever to 4L position.
(b) Remove nut with socket and impact wrench.
(2) Remove companion flange. If flange is difficult
to remove by hand, remove it with bearing splitter, orwith standard two jaw puller. Be sure puller tool is
positioned on flange and not on slinger as slinger will
be damaged.
(3) Remove seal washer from front output shaft.
Discard washer as it should not be reused.
(4) Remove nut and washer that attach range
lever to sector shaft. Then move sector to neutral
position and remove range lever from shaft.
NOTE: Note position of range lever so it can be re-
installed correctly.
Fig. 9 Disengaging Rear Bearing Locating Ring
1 - REAR RETAINER
2 - PARALLEL JAW SNAP-RING PLIERS
Fig. 10 Rear Retainer Removal
1 - REAR CASE
2 - REAR RETAINER
Fig. 11 Rear Bearing and Oil Pump Removal
1 - OIL PUMP
2 - TUBE O-RING
3 - OIL PICKUP TUBE
Fig. 12 Pick-up Tube O-ring Location
1 - OIL PUMP
2 - O-RING
WJTRANSFER CASE - NV247 21 - 319
TRANSFER CASE - NV247 (Continued)

REAR CASE
(1) Support transfer case so rear case is facing
upward.
(2) Remove bolts holding front case to rear case.
The case alignment bolt require flat washers (Fig.
13).
(3) Loosen rear case with flat blade screwdriver to
break sealer bead. Insert screwdriver blade only into
notches provided at each end of case (Fig. 14).
(4) Remove rear case (Fig. 15).
PROGRESSIVE COUPLING
(1) Remove oil pump locating snap-ring and pro-
gressive coupling thrust washer from the mainshaft
(Fig. 16).
(2) Remove progressive coupling from mainshaft
(Fig. 16).
Fig. 13 Rear Case Alignment Bolt Locations
1 - ALIGNMENT BOLT AND WASHER (AT EACH END OF CASE)
Fig. 14 Loosening Rear Case
1 - REAR CASE
2 - PRY TOOL (IN CASE SLOT)
3 - FRONT CASE
Fig. 15 Rear Case Removal
1 - REAR HOUSING
2 - MAINSHAFT
3 - TRANSFER CASE
Fig. 16 Progressive Coupling Removal
1 - SNAP-RING
2 - PROGRESSIVE COUPLING
21 - 320 TRANSFER CASE - NV247WJ
TRANSFER CASE - NV247 (Continued)

FRONT OUTPUT SHAFT AND DRIVE CHAIN
(1) Remove oil pickup tube from rear case (Fig.
17).
(2) Remove drive gear snap-ring (Fig. 18).
(3) Disengage drive gear (Fig. 18). Pry gear
upward and off mainshaft as shown.
(4) Remove front output shaft, drive chain and
drive gear as assembly (Fig. 18).
(5) Remove output shaft drive gear snap ring.
(6) Remove output shaft drive gear from output
shaft.
SHIFT FORKS AND MAINSHAFT
(1) Remove detent plug, O-ring, detent spring and
detent plunger (Fig. 19).
(2) Remove shift rail from shift fork and transfer
case housing.
(3) Rotate range shift fork until it disengages from
shift sector.
(4) Remove mainshaft and shift fork from input
gear pilot bearing.
NOTE: Loose needle bearings are used to support
the drive sprocket hub on the mainshaft. Do not lift
mainshaft by drive sprocket hub or needle bearings
will become dislodged.
(5) Wrap rag around mainshaft underneath drive
sprocket hub and remove drive sprocket hub from
mainshaft. Be sure to retrieve all the drive sprocket
hub needle bearings.
(6) Remove snap ring holding clutch sleeve onto
mainshaft.
Fig. 17 Oil Pickup Tube Removal
1 - OIL PICKUP TUBE
Fig. 18 Front Output Shaft, Drive Gear And Chain
Removal
1 - REAR HOUSING
2 - OUTPUT SHAFT AND SPROCKET
3 - MAINSHAFT SPROCKET
4 - SNAP-RING
5 - DRIVE CHAIN
Fig. 19 Detent Plug, Spring And Plunger Removal
1 - DETENT PLUG
2 - DETENT SPRING
3 - DETENT PLUNGER
4 - PLUG O-RING
WJTRANSFER CASE - NV247 21 - 321
TRANSFER CASE - NV247 (Continued)

(7) Remove range clutch sleeve, blockout spring,
locking clutch, and locking clutch spring from main-
shaft (Fig. 20).
(8) Remove shift sector. Rotate and tilt sector as
needed to remove it (Fig. 21).
(9) Remove shift sector bushing and O-ring (Fig.
22).
INPUT GEAR/LOW RANGE ASSEMBLY
(1) Turn front case on side so front bearing
retainer is accessible.
(2) Remove front bearing retainer bolts (Fig. 23).
(3) Remove front bearing retainer as follows:(a) Loosen retainer with flat blade screwdriver
to break sealer bead.To avoid damaging case
and retainer, position screwdriver blade only
in slots provided in retainer (Fig. 24).
(b) Then remove retainer from case and gear.
Fig. 20 Range Clutch Sleeve, Blockout Spring,
Locking Clutch and Spring
1 - LOCKING CLUTCH SPRING
2 - BLOCKOUT SPRING
3 - SNAP-RING
4 - RANGE CLUTCH SLEEVE
5 - LOCKING CLUTCH
6 - DRIVE SPROCKET HUB
Fig. 21 Shift Sector Removal
1 - SHIFT SECTOR
Fig. 22 Sector Bushing And O-Ring Removal
1 - SHIFT SECTOR BUSHING
2 - O-RING
Fig. 23 Front Bearing Retainer Bolt Removal
1 - FRONT BEARING RETAINER
21 - 322 TRANSFER CASE - NV247WJ
TRANSFER CASE - NV247 (Continued)

(4) Remove snap-ring that retains input gear shaft
in front bearing (Fig. 25).
(5) Remove input and low range gear assembly
(Fig. 26).
(6) Remove oil seals from following components:
²front bearing retainer.
²rear retainer.
²case halves.INPUT AND LOW RANGE GEAR
(1) Remove snap-ring that retains input gear in
low range gear (Fig. 27).
Fig. 24 Front Bearing Retainer Removal
1 - FRONT BEARING RETAINER
2 - RETAINER NOTCH
3 - FLAT BLADE SCREWDRIVER
Fig. 25 Input Gear Snap-Ring Removal
1 - INPUT GEAR
2 - SNAP-RING
Fig. 26 Input And Low Range Gear Assembly
Removal
1 - INPUT AND LOW RANGE GEAR ASSEMBLY
Fig. 27 Input Gear Snap-Ring Removal
1 - INPUT GEAR SNAP-RING
WJTRANSFER CASE - NV247 21 - 323
TRANSFER CASE - NV247 (Continued)