2002 JEEP GRAND CHEROKEE o2 location

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

(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)

INPUT AND LOW RANGE GEARS
Inspect the low range gear pinions and pinion pins.
Replace the low range gear if any of the pins or pin-
ions are worn or damaged.
Inspect the thrust washers, retainer, and snap-
ring. Replace the snap-ring if bent, or distorted.
Replace the thrust washers and retainer if worn,
cracked or damaged in any way.
Examine the input gear carefully. Be sure the gear
teeth and bearing surfaces are in good condition.
Replace the gear if wear or damage is evident.
Check the input gear pilot bearing. Rotate the
bearing and check for roughness or noise. Also check
bearing position in the bore. The bearing should be
recessed approximately 2.5 mm (0.100 in.) below the
top edge of the bore. The bearing should not be
seated at the bottom of the bore. Replace the bearing
if worn, or roughness is evident. Replace both the
gear and bearing if the bearing is a loose fit in the
bore.
GEAR CASE AND RETAINERS
Examine both case halves and retainers carefully.
Replace any retainer or case half if wear, cracks, or
other damage is evident.
Check condition of the low range annulus gear and
the shift rail bushing in the front case (Fig. 32). The
low range annulus gear is not a serviceable part.
Replace the gear and case as an assembly if the gear
is loose, worn, or damaged. The shift rail bushing is
a serviceable part and can be replaced if necessary.
Check the bushing in the rear retainer. Replace the
bushing if worn or scored.
Examine the sealing surfaces of both case halves
and retainers. Small burrs, or scratches on these sur-
faces can be reduced with crocus cloth or a fine tooth
file.
Examine condition of the shift rail bushing in the
front case. If the bushing is worn or damaged, it can
be removed with a blind hole type puller. A replace-
ment bushing can be installed with a suitable size
driver. Recess the bushing slightly below the edge of
the bore but do not seat it all the into the case.
GEARTRAIN
Inspect the mainshaft splines, gear teeth and bear-
ing surfaces carefully for evidence of wear, or dam-
age. Replace the shaft if necessary. do not attempt to
salvage it if damaged.
The shift rail and range fork are an assembly.
Replace both parts if either is damaged. However, the
nylon pads in the fork can be replaced if worn, or
cracked.
Inspect the transfer case snap-rings closely. Do not
attempt to salvage a distorted snap-ring by straight-ening or reshaping it. Replace any snap-ring that is
distorted, or worn.
Inspect the low range gear, input gear and the gear
thrust washers retainer, and snap-ring. The low
range gear is serviced as an assembly only. Replace
the gear if the case or pinions are damaged.
During inspection, also make sure the seal surface
of the input gear is in good condition. Minor nicks on
this surface can be reduced with crocus cloth. How-
ever, replace the gear if the seal surface is severely
scored or worn.
OIL PUMP AND PROGRESSIVE COUPLING
The oil pump and progressive coupling are not ser-
viceable components. Replace the coupling as an
assembly if it is damaged. Replace the oil pump as
an assembly if the gear teeth are worn, or if the
pump has become damaged.
BEARINGS AND SEALS
The transfer case seals should be replaced during
overhaul. Use new seals in the input gear bearing
retainer, front case and rear retainer. Also replace
the yoke seal washer and the detent plug O-ring.
Check condition of each transfer case bearing.
Replace any bearing exhibiting signs of roughness,
wear, or damage.
Fig. 32 Low Range Annulus Gear Location
1 - LOW RANGE ANNULUS GEAR
2 - SHIFT RAIL BUSHING
WJTRANSFER CASE - NV247 21 - 325
TRANSFER CASE - NV247 (Continued)

FLUID
STANDARD PROCEDURE - FLUID DRAIN/
REFILL
The fill and drain plugs are both in the rear case
(Fig. 72).
(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 20-34 N´m
(15-25 ft. lbs.).
(5) Remove drain pan.(6) Fill transfer case to bottom edge of fill plug
opening with MopartTransfer Case Lubricant.
(7) Install and tighten fill plug to 20-34 N´m
(15-25 ft. lbs.).
(8) Lower vehicle.
FRONT OUTPUT SHAFT SEAL
REMOVAL
(1) Raise vehicle on hoist.
(2) Remove front propeller shaft. (Refer to 3 - DIF-
FERENTIAL & DRIVELINE/PROPELLER SHAFT/
PROPELLER SHAFT - REMOVAL)
(3) Remove front output shaft companion shaft.
(4) Remove seal from front case with pry tool (Fig.
73).
INSTALLATION
(1) Install new front output seal in front case with
Installer Tool 6952-A as follows:
(a) Place new seal on tool. Garter spring on seal
goes toward interior of case.
(b) Start seal in bore with light taps from ham-
mer (Fig. 74). Once seal is started, continue tap-
ping seal into bore until installer tool seats against
case.
(2) Install companion flange and torque nut to
122-176 N´m (90-130 ft. lbs.).
(3) Install front propeller shaft. (Refer to 3 - DIF-
FERENTIAL & DRIVELINE/PROPELLER SHAFT/
PROPELLER SHAFT - INSTALLATION)
Installer, Bearign - 8128
Installer, Seal - 7884
Fig. 72 Fill/Drain Plug and I.D. Tag Location -
Typical
1 - I.D. TAG
2 - FILL PLUG
3 - DRAIN PLUG
Fig. 73 Remove Front Output Shaft Seal
1 - OUTPUT SHAFT SEAL
2 - PRYBAR
21 - 338 TRANSFER CASE - NV247WJ
TRANSFER CASE - NV247 (Continued)

(1) Remove tire from wheel and mount wheel on
service dynamic balance machine.
(2) Check wheel radial runout (Fig. 2) and lateral
runout (Fig. 3).
²STEEL WHEELS: Radial runout 0.040 in., Lat-
eral runout 0.045 in. (maximum)
²ALUMINUM WHEELS: Radial runout 0.030 in.,
Lateral runout 0.035 in. (maximum)
(3) If point of greatest wheel lateral runout is near
original chalk mark, remount tire 180 degrees.
Recheck runout,(Refer to 22 - TIRES/WHEELS -
STANDARD PROCEDURE) .
STANDARD PROCEDURE
STANDARD PROCEDURE - TIRE AND WHEEL
BALANCE
It is recommended that a two plane service
dynamic balancer be used when a tire and wheel
assembly require balancing. Refer to balancer opera-
tion instructions for proper cone mounting proce-
dures. Typically use front cone mounting method for
steel wheels. For aluminum wheel use back cone
mounting method without cone spring.
NOTE: Static should be used only when a two plane
balancer is not available.
NOTE: Cast aluminum and forged aluminum wheels
require coated balance weights and special align-
ment equipment.
Wheel balancing can be accomplished with either
on or off vehicle equipment. When using on-vehiclebalancing equipment, remove the opposite wheel/tire.
Off-vehicle balancing is recommended.
For static balancing, find the location of the heavy
spot causing the imbalance. Counter balance wheel
directly opposite the heavy spot. Determine weight
Fig. 1 Checking Tire/Wheel/Hub Runout
1 - RADIAL RUNOUT
2 - LATERAL RUNOUT
Fig. 2 Radial Runout
1 - MOUNTING CONE
2 - SPINDLE SHAFT
3 - WING NUT
4 - PLASTIC CUP
5 - DIAL INDICATOR
6 - WHEEL
7 - DIAL INDICATOR
Fig. 3 Lateral Runout
1 - MOUNTING CONE
2 - SPINDLE SHAFT
3 - WING NUT
4 - PLASTIC CUP
5 - DIAL INDICATOR
6 - WHEEL
7 - DIAL INDICATOR
22 - 2 TIRES/WHEELSWJ
TIRES/WHEELS (Continued)

required to counter balance the area of imbalance.
Place half of this weight on theinnerrim flange and
the other half on theouterrim flange (Fig. 4).For dynamic balancing, the balancing equipment is
designed to locate the amount of weight to be applied
to both the inner and outer rim flange (Fig. 5).
Fig. 4 Static Unbalance & Balance
1 - HEAVY SPOT
2 - CENTER LINE OF SPINDLE
3 - ADD BALANCE WEIGHTS HERE4 - CORRECTIVE WEIGHT LOCATION
5 - TIRE OR WHEEL TRAMP, OR WHEEL HOP
Fig. 5 Dynamic Unbalance & Balance
1 - CENTER LINE OF SPINDLE
2 - ADD BALANCE WEIGHTS HERE3 - CORRECTIVE WEIGHT LOCATION
4 - HEAVY SPOT WHEEL SHIMMY AND VIBRATION
WJTIRES/WHEELS 22 - 3
TIRES/WHEELS (Continued)

STANDARD PROCEDURE - MATCH MOUNTING
Tires and wheels are currently not match mounted
at the factory. Match mounting is a technique used to
reduce runout in the wheel/tire assembly. This means
that the high spot of the tire is aligned with the low
spot on the wheel rim. The high spot on the tire is
marked with a paint mark or a bright colored adhe-
sive label on the outboard sidewall. The low spot on
the rim is identified with a label on the outside of the
rim and a dot on the inside of the rim. If the outside
label has been removed the tire will have to be
removed to locate the dot on the inside of the rim.
Before dismounting a tire from its wheel, a refer-
ence mark should be placed on the tire at the valve
stem location. This reference will ensure that it is
remounted in the original position on the wheel.
(1) Use a dial indicator to locate the high spot of
the tire on the center tread rib (Fig. 6). Record the
indicator reading and mark the high spot on the tire.
Place a mark on the tire at the valve stem location
(Fig. 7).
(2) Break down the tire and remount it 180
degrees on the rim (Fig. 8).
(3) Measure the total runout again and mark the
tire to indicate the high spot.
(4) If runout is still excessive use the following
procedures.
(a) If the high spot is within 101.6 mm (4.0 in.)
of the first spot and is still excessive, replace the
tire.
(b) If the high spot is within 101.6 mm (4.0 in.)
of the first spot on the wheel, the wheel may be out
of specifications,(Refer to 22 - TIRES/WHEELS -
DIAGNOSIS AND TESTING).
(c) If the high spot is NOT within 101.6 mm (4.0
in.) of either high spot, draw an arrow on the tread
from second high spot to first. Break down the tire
and remount it 90 degrees on rim in that direction
(Fig. 9). This procedure will normally reduce the
runout to an acceptable amount.
Fig. 6 Dial Indicator
Fig. 7 First Measurement On Tire
1 - REFERENCE MARK
2 - 1ST MEASUREMENT
HIGH SPOT MARK TIRE AND RIM
3 - WHEEL
4 - VALVE STEM
Fig. 8 Remount Tire 180 Degrees
1 - VALVE STEM
2 - REFERENCE MARK
22 - 4 TIRES/WHEELSWJ
TIRES/WHEELS (Continued)