2002 JEEP GRAND CHEROKEE Vin

be in the downshifted position, thus directing fluid to
the L/R clutch circuit. In 2nd, 3rd, 4th, and fifth
gears, the solenoid switch valve will be in the
upshifted position and directs the fluid into the
torque converter clutch (TCC) circuit.
When shifting into 1st gear, a special hydraulic
sequence is performed to ensure SSV movement into
the downshifted position. The L/R pressure switch is
monitored to confirm SSV movement. If the move-
ment is not confirmed (the L/R pressure switch does
not close), 2nd gear is substituted for 1st. A DTC will
be set after three unsuccessful attempts are made to
get into 1st gear in one given key start.
MANUAL VALVE
The manual valve is a relay valve. The purpose of
the manual valve is to direct fluid to the correct cir-
cuit needed for a specific gear or driving range. The
manual valve, as the name implies, is manually oper-
ated by the driver with a lever located on the top of
the valve body. The valve is connected mechanically
by a cable to the gearshift mechanism. The valve is
held in each of its positions by a roller detent spring
(Fig. 123) that engages the ªroostercombº of the TRS
selector plate.
LOW/REVERSE SWITCH VALVE
The low/reverse switch valve allows the low/reverse
clutch to be operated by either the LR/CC solenoid or
the MS solenoid.
REMOVAL
The valve body can be removed for service without
having to remove the transmission assembly.
The valve body can be disassembled for cleaning
and inspection of the individual components. (Refer
to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC
- 45RFE/VALVE BODY - DISASSEMBLY)
(1) Shift transmission into PARK.
(2) Raise vehicle.
(3) Disconnect wires at the solenoid and pressure
switch assembly connector.
(4) Position drain pan under transmission oil pan.
(5) Remove transmission oil pan.
(6) Remove the primary oil filter from valve body.
(Fig. 124)
Fig. 123 TRS Selector Plate and Detent Spring
1 - TRS SELECTOR PLATE
2 - DETENT SPRING
3 - CLUTCH PASSAGE SEALS
Fig. 124 Remove Primary Oil Filter
1 - PRIMARY OIL FILTER
2 - COOLER RETURN FILTER
3 - COOLER RETURN FILTER BYPASS VALVE
4 - VALVE BODY
21 - 274 AUTOMATIC TRANSMISSION - 545RFEWJ
VALVE BODY (Continued)

(5) Remove rear case from front case (Fig. 17).
Insert screwdrivers into slots cast into each end of
case. Then pry upward to break sealer bead and
remove rear case.
CAUTION: Do not pry on the sealing surface of
either case half as the surfaces will become dam-
aged.
(6) Remove oil pickup tube and screen from rear
case (Fig. 18).
Fig. 14 Oil Pump Removal
1 - OIL PUMP
Fig. 15 Pickup Tube O-Ring Location
1 - OIL PUMP
2 - O-RING
Fig. 16 Spline And Dowel Bolt Locations
1 - DOWEL BOLT AND WASHER (2)
2 - CASE BOLTS
3 - SPLINE HEAD BOLT (1)
Fig. 17 Loosening/Removing Rear Case
1 - MAINSHAFT
2 - SCREWDRIVER
3 - FRONT CASE
4 - SCREWDRIVER
5 - REAR CASE
Fig. 18 Oil Pickup Screen, Hose And Tube Removal
1 - CONNECTING HOSE
2 - PICKUP SCREEN
3 - PICKUP TUBE
WJTRANSFER CASE - NV242 21 - 285
TRANSFER CASE - NV242 (Continued)

FRONT OUTPUT SHAFT AND DRIVE CHAIN
(1) Remove drive sprocket snap-ring (Fig. 23).
(2) Remove drive sprocket and chain (Fig. 24).
(3) Remove front output shaft (Fig. 25).
SHIFT FORKS AND MAINSHAFT
(1) Remove shift detent plug, spring and pin (Fig.
26).
Fig. 23 Drive Sprocket Snap-Ring Removal
1 - DRIVE SPROCKET
2 - DRIVE SPROCKET SNAP-RING
Fig. 24 Drive Sprocket And Chain Removal
1 - DRIVE SPROCKET
2 - DRIVE CHAIN
Fig. 25 Removing Front Output Shaft
1 - FRONT OUTPUT SHAFT
Fig. 26 Detent Component Removal
1 - PLUNGER
2 - O-RING
3 - PLUG
4 - SPRING
WJTRANSFER CASE - NV242 21 - 287
TRANSFER CASE - NV242 (Continued)

(6) Remove input gear bearing with Tool Handle
C-4171 and Remover C-4210 (Fig. 55).
(7) Install snap-ring on new input gear bearing.
(8) Install new input gear bearing with Tool Han-
dle C-4171 and Remover C-4210. Install bearing far
enough to seat snap-ring against case (Fig. 56).
(9) Remove the input gear pilot bearing by insert-
ing a suitably sized drift into the splined end of the
input gear and driving the bearing out with the drift
and a hammer (Fig. 57).(10) Install new pilot bearing with Installer 8128
and Handle C-4171 (Fig. 58).
Fig. 55 Input Gear Bearing Removal
1 - SPECIAL TOOL C-4171
2 - SPECIAL TOOL C-4210
Fig. 56 Seating Input Gear Bearing
1 - SNAP-RING
2 - INPUT SHAFT BEARING
Fig. 57 Remove Input Gear Pilot Bearing
1 - DRIFT
2 - INPUT GEAR
Fig. 58 Install Input Gear Pilot Bearing
1 - HANDLE C-4171
2 - INSTALLER 8128
3 - INPUT GEAR
WJTRANSFER CASE - NV242 21 - 297
TRANSFER CASE - NV242 (Continued)

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)

(9) Using Remover C-4210 and Handle C-4171,
drive input shaft bearing from inside the annulus
gear opening in the case. (Fig. 40).
(10) Install locating ring on new bearing.
(11) Position case so forward end is facing upward.
(12) Using Remover C-4210 and Handle C-4171,
drive input shaft bearing into case. The bearing
locating ring must be fully seated against case sur-
face (Fig. 41).
(13) Remove input gear pilot bearing by inserting
a suitably sized drift into the splined end of the inputgear and driving the bearing out with the drift and a
hammer (Fig. 42).
(14) Install new pilot bearing with Installer 8128
and Handle C-4171 (Fig. 43).
Fig. 40 Input Shaft Bearing Removal
1 - SPECIAL TOOL C-4171
2 - SPECIAL TOOL C-4210
Fig. 41 Seating Input Shaft Bearing
1 - SNAP-RING
2 - INPUT SHAFT BEARING
Fig. 42 Remove Input Gear Pilot Bearing
1 - DRIFT
2 - INPUT GEAR
Fig. 43 Install Input Gear Pilot Bearing
1 - HANDLE C-4171
2 - INSTALLER 8128
3 - INPUT GEAR
21 - 328 TRANSFER CASE - NV247WJ
TRANSFER CASE - NV247 (Continued)

STANDARD PROCEDURE - TIRE ROTATION
Tires on the front and rear operate at different
loads and perform different steering, driving, and
braking functions. For these reasons they wear at
unequal rates and tend to develop irregular wear
patterns. These effects can be reduced by rotating
the tires at regular intervals. The benefits of tire
rotation are:
²Increase tread life
²Maintain traction levels
²A smooth, quiet ride
The suggested method of tire rotation is (Fig. 10).
Other rotation methods can be used, but they will
not provide all the tire longevity benefits.
STANDARD PROCEDURE - WHEEL
INSTALLATION
The wheel studs and nuts are designed for specific
applications. They must be replaced with equivalent
parts. Do not use replacement parts of lesser quality
or a substitute design. All aluminum and some steel
wheels have wheel stud nuts which feature an
enlarged nose. This enlarged nose is necessary to
ensure proper retention of the aluminum wheels.
NOTE: Do not use chrome plated lug nuts with
chrome plated wheels.
Before installing the wheel, be sure to remove any
build up of corrosion on the wheel mounting surfaces.
Ensure wheels are installed with good metal-to-metal
contact. Improper installation could cause loosening
of wheel nuts. This could affect the safety and han-
dling of your vehicle.
To install the wheel, first position it properly on
the mounting surface. All wheel nuts should then be
tightened just snug. Gradually tighten them in
sequence to the proper torque specification (Fig. 11).
Never use oil or grease on studs or nuts.
Fig. 9 Remount Tire 90 Degrees In Direction of
Arrow
1 - 2ND HIGH SPOT ON TIRE
2 - 1ST HIGH SPOT ON TIRE
Fig. 10 Tire Rotation Pattern
Fig. 11 LUG NUT TIGHTENING PATTERN - TYPICAL
WJTIRES/WHEELS 22 - 5
TIRES/WHEELS (Continued)

TIRES
DESCRIPTION
DESCRIPTION - TIRES
Tires are designed and engineered for each specific
vehicle. They provide the best overall performance
for normal operation. The ride and handling charac-
teristics match the vehicle's requirements. With
proper care they will give excellent reliability, trac-
tion, skid resistance, and tread life.
Driving habits have more effect on tire life than
any other factor. Careful drivers will obtain in most
cases, much greater mileage than severe use or care-
less drivers. A few of the driving habits which will
shorten the life of any tire are:
²Rapid acceleration
²Severe brake applications
²High speed driving
²Excessive speeds on turns
²Striking curbs and other obstacles
Radial-ply tires are more prone to irregular tread
wear. It is important to follow the tire rotation inter-
val shown in the section on Tire Rotation.(Refer to 22
- TIRES/WHEELS - STANDARD PROCEDURE),
This will help to achieve a greater tread life.
TIRE IDENTIFICATION
Tire type, size, aspect ratio and speed rating are
encoded in the letters and numbers imprinted on the
side wall of the tire. Refer to the chart to decipher
the tire identification code (Fig. 12).
Performance tires have a speed rating letter after
the aspect ratio number. The speed rating is not
always printed on the tire sidewall. These ratings
are:
²Qup to 100 mph
²Sup to 112 mph
²Tup to 118 mph
²Uup to 124 mph
²Hup to 130 mph
²Vup to 149 mph
²Zmore than 149 mph (consult the tire manu-
facturer for the specific speed rating)
An All Season type tire will have eitherM+S,M
&SorM±S(indicating mud and snow traction)
imprinted on the side wall.
TIRE CHAINS
Tire snow chains may be used oncertainmodels.
Refer to the Owner's Manual for more information.
DESCRIPTION - RADIAL±PLY TIRES
Radial-ply tires improve handling, tread life and
ride quality, and decrease rolling resistance.Radial-ply tires must always be used in sets of
four. Under no circumstances should they be used on
the front only. They may be mixed with temporary
spare tires when necessary. A maximum speed of 50
MPH is recommended while a temporary spare is in
use.
Radial-ply tires have the same load-carrying capac-
ity as other types of tires of the same size. They also
use the same recommended inflation pressures.
The use of oversized tires, either in the front or
rear of the vehicle, can cause vehicle drive train fail-
ure. This could also cause inaccurate wheel speed
signals when the vehicle is equipped with Anti-Lock
Brakes.
The use of tires from different manufactures on the
same vehicle is NOT recommended. The proper tire
pressure should be maintained on all four tires.
DESCRIPTION - TIRE INFLATION PRESSURES
Under inflation will cause rapid shoulder wear, tire
flexing, and possible tire failure (Fig. 13).
Over inflation will cause rapid center wear and
loss of the tire's ability to cushion shocks (Fig. 14).
Improper inflation can cause:
²Uneven wear patterns
²Reduced tread life
²Reduced fuel economy
Fig. 12 Tire Identification
22 - 6 TIRES/WHEELSWJ