Rear differential JEEP GRAND CHEROKEE 2002 WJ / 2.G Manual PDF

STANDARD PROCEDURE - DISC ROTOR
MACHINING
CAUTION: For vehicles equipped with the Quadra-
Drive System, consisting of the NV-247 transfer case
and a Vari-Lok differential in the front and rear axles,
the following steps must be done prior to the use of a
hub mounted on-vehicle brake lathe. Disconnect the
driveshaft (Refer to 3 - DIFFERENTIAL & DRIVELINE/
PROPELLER SHAFT/PROPELLER SHAFT - REMOVAL)
from the respective axle on which the brake rotors are
being machined. Temporarily remove both brake cali-
pers (Refer to 5 - BRAKES/HYDRAULIC/MECHANICAL/
DISC BRAKE CALIPERS - REMOVAL) from the axle
while disc rotor machining is in process. Both steps
will prevent unnecessary loads to the hub mounted
on-vehicle lathe and speed machining times. Install a
thread lock material to the driveshaft attaching bolts
when reinstalling (Refer to 3 - DIFFERENTIAL & DRIV-
ELINE/PROPELLER SHAFT/PROPELLER SHAFT -
INSTALLATION).
NOTE: A hub mounted on-vehicle lathe is recom-
mended. This type of lathe trues the rotor to the vehi-
cles hub/bearing.
The disc brake rotor can be machined if scored or
worn. The lathe must machine both sides of the rotor
simultaneously with dual cutter heads. The rotor
mounting surface must be clean before placing on the
lathe. Equipment capable of machining only one side at
a time may produce a tapered rotor.
CAUTION: Brake rotors that do not meet minimum
thickness specifications before or after machining
must be replaced.
REMOVAL
REMOVAL - FRONT DISC BRAKE ROTOR
NOTE: Front rotors and hub/bearings are matched
mounted for minimum lateral runout. Before removing
the rotor, mark the rotor and hub/bearing to maintain
original orientation.
(1) Raise and support the vehicle.
(2) Remove wheel and tire assembly.
(3) Remove the caliper anchor bolts (Fig. 64) and
remove the caliper and anchor as an assembly from the
steering knuckle.
(4) Secure caliper anchor assembly to nearby suspen-
sion part with a wire.Do not allow brake hose to
support caliper weight.
(5) Mark the rotor and hub/bearing to maintain orig-
inal orientation. Remove retainers securing rotor to hub
studs.
(6) Remove rotor from hub/bearing.
REMOVAL - REAR DISC BRAKE ROTOR
(1) Raise and support the vehicle.
(2) Remove wheel and tire assembly.
(3) Remove the caliper anchor bolts (Fig. 65).
(4) Remove caliper and anchor as an assembly.(5) Secure caliper anchor assembly to nearby suspen-
sion part with wire.Do not allow brake hose to sup-
port caliper weight.
(6) Remove retainers securing rotor to axle studs.
(7) Remove rotor off axle studs.
Fig. 64 Caliper Anchor Bolts
1 - KNUCKLE
2 - ANCHOR
3 - ANCHOR BOLTS
4 - ROTOR
Fig. 65 Caliper Anchor Bolts
1 - ROTOR
2 - ANCHOR
3 - ANCHOR BOLTS
WJBRAKES - BASE 5 - 33
ROTORS (Continued)
2002 WJ Service Manual
Publication No. 81-370-02064
02WJ5-33 June, 2002

DIAGNOSIS AND TESTING - OVERDRIVE
ELECTRICAL CONTROLS
The overdrive off switch, valve body solenoid, case
connectors and related wiring can all be tested with
a 12 volt test lamp or a volt/ohmmeter. Check conti-
nuity of each component when diagnosis indicates
this is necessary.
Switch and solenoid continuity should be checked
whenever the transmission fails to shift into fourth
gear range.
OVERDRIVE UNIT
REMOVAL
(1) Shift transmission into PARK.
(2) Raise vehicle.
(3) Remove transfer case, if equipped.
(4) Mark propeller shaft universal joint(s) and axle
pinion yoke, or the companion flange and flange
yoke, for alignment reference at installation, if necc-
esary.
(5) Disconnect and remove the rear propeller shaft,
if necessary. (Refer to 3 - DIFFERENTIAL & DRIV-
ELINE/PROPELLER SHAFT/PROPELLER SHAFT -
REMOVAL)
(6) Remove transmission oil pan, remove gasket,
drain oil and reinstall pan.
(7) If overdrive unit had malfunctioned, or if fluid
is contaminated, remove entire transmission. If diag-
nosis indicated overdrive problems only, remove just
the overdrive unit.
(8) Support transmission with transmission jack.
(9) Remove bolts attaching overdrive unit to trans-
mission (Fig. 126).
CAUTION: Support the overdrive unit with a jack
before moving it rearward. This is necessary to pre-
vent damaging the intermediate shaft. Do not allow
the shaft to support the entire weight of the over-
drive unit.(10) Carefully work overdrive unit off intermediate
shaft. Do not tilt unit during removal. Keep it as
level as possible.
(11) If overdrive unit does not require service,
immediately insert Alignment Tool 6227-2 in splines
of planetary gear and overrunning clutch to prevent
splines from rotating out of alignment. If misalign-
ment occurs, overdrive unit will have to be disassem-
bled in order to realign splines.
(12) Remove and retain overdrive piston thrust
bearing. Bearing may remain on piston or in clutch
hub during removal.
(13) Position drain pan on workbench.
(14) Place overdrive unit over drain pan. Tilt unit
to drain residual fluid from case.
(15) Examine fluid for clutch material or metal
fragments. If fluid contains these items, overhaul will
be necessary.
(16) If overdrive unit does not require any service,
leave alignment tool in position. Tool will prevent
accidental misalignment of planetary gear and over-
running clutch splines.Fig. 126 Overdrive Unit Bolts
1 - OVERDRIVE UNIT
2 - ATTACHING BOLTS (7)
WJAUTOMATIC TRANSMISSION - 42RE 21 - 87
OVERDRIVE OFF SWITCH (Continued)

CAUTION: Be sure the shoulder on the inside diam-
eter of the bearing is facing forward.
(8) Verify that splines in overdrive planetary gear
and overrunning clutch hub are aligned with Align-
ment Tool 6227-2. Overdrive unit cannot be installed
if splines are not aligned. If splines have rotated out
of alignment, unit will have to be disassembled to
realign splines.
(9) Carefully slide Alignment Tool 6227-2 out of
overdrive planetary gear and overrunning clutch
splines.
(10) Raise overdrive unit and carefully slide it
straight onto intermediate shaft. Insert park rod into
park lock reaction plug at same time. Avoid tilting
overdrive during installation as this could cause
planetary gear and overrunning clutch splines to
rotate out of alignment. If this occurs, it will be nec-essary to remove and disassemble overdrive unit to
realign splines.
(11) Work overdrive unit forward on intermediate
shaft until seated against transmission case.
(12) Install bolts attaching overdrive unit to trans-
mission unit. Tighten bolts in diagonal pattern to 34
N´m (25 ft-lbs).
(13) Connect the transmission speed sensor and
overdrive wiring connectors.
(14) Install the transfer case, if equipped.
(15) Align and install rear propeller shaft, if nec-
essary. (Refer to 3 - DIFFERENTIAL & DRIVELINE/
PROPELLER SHAFT/PROPELLER SHAFT -
INSTALLATION)
OVERRUNNING CLUTCH
CAM/OVERDRIVE PISTON
RETAINER
DESCRIPTION
The overrunning clutch (Fig. 189) consists of an
inner race, an outer race (or cam), rollers and
springs, and the spring retainer. The number of roll-
ers and springs depends on what transmission and
which overrunning clutch is being dealt with.
OPERATION
As the inner race is rotated in a clockwise direction
(as viewed from the front of the transmission), the
race causes the rollers to roll toward the springs,
causing them to compress against their retainer. The
compression of the springs increases the clearance
Fig. 187 Trimming Overdrive Case Gasket
1 - GASKET
2 - SHARP KNIFE
Fig. 188 Intermediate Shaft Selective Spacer
Location
1 - SELECTIVE SPACER
2 - SPACER GROOVE
3 - INTERMEDIATE SHAFT
Fig. 189 Overrunning Clutch
1 - OUTER RACE (CAM)
2 - ROLLER
3 - SPRING
4 - SPRING RETAINER
5 - INNER RACE (HUB)
WJAUTOMATIC TRANSMISSION - 42RE 21 - 105
OVERDRIVE UNIT (Continued)

Once the TCC control valve has moved to the right
(Fig. 275), line pressure is directed to the tip of the
switch valve, forcing the valve to the right. The
switch valve now vents oil from the front of the pis-
ton in the torque converter, and supplies line pres-
sure to the (rear) apply side of the torque converter
piston. This pressure differential causes the piston toapply against the friction material, cutting off any
further flow of line pressure oil. After the switch
valve is shuttled right allowing line pressure to
engage the TCC, torque converter pressure is
directed past the switch valve into the transmission
cooler and lubrication circuits.
Fig. 275 Switch Valve-Torque Converter Locked
21 - 152 AUTOMATIC TRANSMISSION - 42REWJ
VALVE BODY (Continued)

TRANSFER CASE - NV242
TABLE OF CONTENTS
page page
TRANSFER CASE - NV242
DESCRIPTION........................280
OPERATION..........................281
DIAGNOSIS AND TESTING - TRANSFER
CASE - NV242.......................281
REMOVAL............................282
DISASSEMBLY........................282
CLEANING...........................292
INSPECTION.........................293
ASSEMBLY...........................295
INSTALLATION........................307
SPECIFICATIONS
TRANSFER CASE - NV242.............308
SPECIAL TOOLS
TRANSFER CASE - NV242.............308
FLUID
STANDARD PROCEDURE - FLUID DRAIN/
REFILL............................310FRONT OUTPUT SHAFT SEAL
REMOVAL............................310
INSTALLATION........................310
POSITION SENSOR
DESCRIPTION........................311
OPERATION..........................311
REMOVAL............................312
INSTALLATION........................312
REAR RETAINER BUSHING AND SEAL -
NV242HD
REMOVAL............................312
INSTALLATION........................312
SHIFT CABLE
REMOVAL............................313
INSTALLATION........................313
TRANSFER CASE - NV242
DESCRIPTION
The NV242 is a full transfer case (Fig. 1). It pro-
vides full time 2-wheel, or 4-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 provides increased low speed torque capa-
bility 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.
TRANSFER CASE IDENTIFICATION
Two versions of the NV242 are used in the WJ
vehicles, NV242LD and NV242HD. The two transfer
cases can be distinguished from one another by the
rear output shaft retainer. The NV242LD uses a rub-
ber boot to cover the rear output shaft, while the
NV242HD uses a cast aluminum housing. Other than
this difference, the two transfer cases are serviced
the same.
A circular ID tag is attached to the rear case of
each transfer case (Fig. 2). 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.
SHIFT MECHANISM
Operating ranges are selected with a lever in the
floor mounted shifter assembly. The shift lever is con-
nected to the transfer case range lever by an adjust-
able cable. A straight line shift pattern is used.
Range positions are marked on the shifter bezel.
Fig. 1 NV242 Transfer Case
21 - 280 TRANSFER CASE - NV242WJ

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. 3).
(7) Disconnect front/rear propeller shafts at trans-
fer case. (Refer to 3 - DIFFERENTIAL & DRIV-
ELINE/PROPELLER SHAFT/PROPELLER SHAFT -
REMOVAL)
(8) Disconnect transfer case cable from range
lever.
(9) Disconnect transfer case vent hose (Fig. 4) and
transfer case position sensor.
(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.
(14) Remove transfer case from under vehicle.
DISASSEMBLY
REAR RETAINER - NV242LD
(1) Remove output shaft boot. Spread band clamp
that secures boot on slinger with a suitable awl.
Then slide boot off shaft (Fig. 5).
Fig. 3 Crossmember Removal
1 - CROSSMEMBER
2 - REAR TRANSMISSION MOUNT
Fig. 4 Transfer Case Mounting
1 - NV242 TRANSFER CASE
Fig. 5 Output Boot - Typical
1 - SLINGER
2 - BOOT
3-AWL
4 - TRANSFER CASE
21 - 282 TRANSFER CASE - NV242WJ
TRANSFER CASE - NV242 (Continued)

(7) Inspect low range annulus gear (Fig. 42).Gear
is not a serviceable component. If damaged,
replace gear and front case as assembly.
(8) Remove oil seals from following components:
²front bearing retainer.
²rear retainer.
²oil pump.
²case halves.
DIFFERENTIAL
(1) Mark differential case halves for reference.
(2) Remove differential case bolts.
(3) Invert differential on workbench.
(4) Separate top case from bottom case. Use slots
in case halves to pry them apart (Fig. 43).
(5) Remove thrust washers and planet gears from
case pins (Fig. 44).
(6) Remove mainshaft and sprocket gears from
bottom case (Fig. 45). Note gear position for reference
before separating them.
CLEANING
Clean the transfer case parts with a standard
parts cleaning solvent. Remove all traces of sealer
from the cases and retainers with a scraper and all
purpose cleaner. Use compressed air to remove sol-
vent residue from oil feed passages in the case
halves, retainers, gears, and shafts.
The oil pickup screen can be cleaned with solvent.
Shake excess solvent from the screen after cleaning
and allow it to air dry. Do not use compressed air.
Fig. 42 Inspecting Low Range Annulus Gear
1 - LOW RANGE ANNULUS GEAR
Fig. 43 Separating Differential Case Halves
1 - TOP CASE
2 - CASE BOLTS
3 - CASE BOLTS
4 - CASE SLOTS
5 - CASE BOLTS
Fig. 44 Planet Gears And Thrust Washer Removal
1 - MAINSHAFT GEAR
2 - THRUST WASHERS (12)
3 - PLANET GEARS (6)
21 - 292 TRANSFER CASE - NV242WJ
TRANSFER CASE - NV242 (Continued)

(15) Install new pickup tube O-ring in oil pump
(Fig. 63).
(16) Remove rear retainer bearing with Installer
8128 and Handle C-4171, NV242HD only.
(17) Install rear bearing in retainer with Handle
C-4171 and Installer 5064 (Fig. 64), NV242HD only.
DIFFERENTIAL
(1) Lubricate differential components with auto-
matic transmission fluid.
(2) Install sprocket gear in differential bottom case
(Fig. 65).(3) Install differential planet gears and new thrust
washers (Fig. 66).Be sure thrust washers are
installed at top and bottom of each planet gear.
(4) Install differential mainshaft gear (Fig. 66).
Fig. 63 Pickup Tube O-Ring Installation
1 - PICKUP TUBE O-RING
Fig. 64 Installing Rear Bearing In Retainer
1 - SPECIAL TOOL C-4171
2 - SPECIAL TOOL 5064
3 - REAR RETAINER
Fig. 65 Installing Differential Sprocket Gear
1 - SPROCKET GEAR
2 - BOTTOM CASE
Fig. 66 Installing Mainshaft And Planet Gears
1 - MAINSHAFT GEAR
2 - THRUST WASHERS (12)
3 - PLANET GEARS (6)
WJTRANSFER CASE - NV242 21 - 299
TRANSFER CASE - NV242 (Continued)

NV242HD REAR RETAINER
(1) Apply bead of MopartSealer, or LoctiteŸ
Ultra Gray, to mating surface of rear retainer. Sealer
bead should be a maximum of 3/16 in.
(2) Install rear retainer on rear case. Tighten
retainer bolts to 20-27 N´m (15-20 ft. lbs.) torque.
(3) Install new output shaft bearing snap-ring
(Fig. 91). Lift mainshaft slightly to seat snap-ring in
shaft groove, if necessary.
(4) Apply 3 mm (1/8 in.) wide bead of Mopartgas-
ket maker or silicone adhesive sealer to mounting
surface of extension housing. Allow sealer to set-up
slightly before proceeding.(5) Install extension housing on rear retainer.
(6) Install extension housing bolts and tighten to
35-46 N´m (26-34 ft. lbs.).
COMPANION FLANGE
(1) Lubricate companion flange hub with transmis-
sion fluid and install flange on front shaft.
(2) Install new seal washer on front shaft.
(3) Install flange on front shaft and tighten nut to
122-176 N´m (90-130 ft. lbs.).
INSTALLATION
(1) Mount transfer case on a transmission jack.
(2) Secure transfer case to jack with chains.
(3) Position transfer case under vehicle.
(4) Align transfer case and transmission shafts
and install transfer case on transmission.
(5) Install and tighten transfer case attaching nuts
to 35 N´m (26 ft. lbs.) torque (Fig. 4).
(6) Align and connect propeller shafts. (Refer to 3 -
DIFFERENTIAL & DRIVELINE/PROPELLER
SHAFT/PROPELLER SHAFT - INSTALLATION)
(7) Fill transfer case with correct fluid. Check
transmission fluid level. Correct as necessary.
(8) Install rear crossmember and skid plate, if
equipped. Tighten crossmember bolts to 41 N´m (30
ft. lbs.) torque.
(9) Remove transmission jack and support stand.
(10) Connect shift rod to transfer case range lever.
(11) Connect transfer case vent hose and transfer
case position sensor.
(12) Adjust transfer case shift cable.
(13) Lower vehicle and verify transfer case shift
operation.
Fig. 91 Install Output Bearing Snap-ring
1 - REAR RETAINER
2 - SNAP-RING
3 - REAR BEARING
WJTRANSFER CASE - NV242 21 - 307
TRANSFER CASE - NV242 (Continued)

(5) Install the rear propeller shaft. (Refer to 3 -
DIFFERENTIAL & DRIVELINE/PROPELLER
SHAFT/PROPELLER SHAFT - INSTALLATION)
(6) Verify proper fluid level.
(7) Lower vehicle.
SHIFT CABLE
REMOVAL
(1) Shift transfer case into NEUTRAL.
(2) Raise vehicle.
(3) Disconnect the shift cable eyelet from the
transfer case shift lever (Fig. 101).
(4) Remove shift cable from the cable support
bracket.
(5) Lower vehicle.
(6) Remove any necessary console parts for access
to shift lever assembly and shift cable.(7) Disconnect cable at shift lever and shifter
assembly bracket (Fig. 102).
(8) Remove the nuts holding the shift cable seal
plate to the floor pan (Fig. 103).
(9) Pull cable through floor panel opening.
(10) Remove transfer case shift cable from vehicle.
INSTALLATION
(1) Route cable through hole in floor pan.
(2) Install seal plate to studs in floor pan.
(3) Install nuts to hold seal plate to floor pan (Fig.
103). Tighten nuts to 7 N´m (65 in.lbs.).
Fig. 100 Install Rear Retainer Seal
1 - SPECIAL TOOL C-4171
2 - SPECIAL TOOL C-3995-A
Fig. 101 Transfer Case Shift Cable at Transfer Case
1 - TRANSFER CASE SHIFT LEVER
2 - TRANSFER CASE SHIFT CABLE
Fig. 102 Transfer Case Shift Cable at Shifter
1 - CLIP
2 - SHIFTER
3 - TRANSFER CASE SHIFT LEVER PIN
4 - TRANSFER CASE SHIFT CABLE
Fig. 103 Shift Cables at Floor Pan
1 - SEAL PLATES
2 - TRANSMISSION SHIFT CABLE
3 - TRANSFER CASE SHIFT CABLE
WJTRANSFER CASE - NV242 21 - 313
REAR RETAINER BUSHING AND SEAL - NV242HD (Continued)