Oil plug JEEP GRAND CHEROKEE 2002 WJ / 2.G Owners Manual

DIAGNOSIS AND TESTING - HYDRAULIC
PRESSURE TEST
An accurate tachometer and pressure test gauges
are required. Test Gauge C-3293-SP has a 300 psi
range and is used at all locations where pressures
exceed 100 psi.
Pressure Test Port Locations
Only two pressure ports are supplied on the trans-
mission case. The torque converter clutch apply and
release ports are located on the right side of the
transmission case (Fig. 2).
To determine the line pressure, there are two avail-
able methods. The DRBtscan tool can be used to
read line pressure from the line pressure sensor. The
second method is to install Line Pressure Adapter
8259 (Fig. 4) into the transmission case and then
install the pressure gauge and the original sensor
into the adapter. This will allow a comparison of the
DRBtreadings and the gauge reading to determe the
accuracy of the line pressure sensor. The DRBtline
pressure reading should match the gauge reading
within  10 psi.
In order to access any other pressure tap locations,
the transmission oil pan must be removed, the pres-
sure port plugs removed and Valve Body Pressure
Tap Adapter 8258-A (Fig. 5) installed. The extensions
supplied with Adapter 8258-A will allow the installa-
tion of pressure gauges to the valve body. Refer to
(Fig. 3) for correct pressure tap location identifica-
tion.
TEST PROCEDURE
All pressure readings should be taken with the
transmission fluid level full, transmission oil at the
normal operating temperature, and the engine at
1500 rpm. Check the transmission for proper opera-
tion in each gear position that is in question or if a
specific element is in question, check the pressure
readings in at least two gear positions that employ
that element. Refer to the Hydraulic Schematics at
the rear of this section to determine the correct pres-
sures for each element in a given gear position.
Fig. 2 Torque Converter Pressure Locations
1 - TCC RELEASE
2 - TO COOLER
3 - TCC APPLY
4 - FROM COOLER
5 - LINE PRESSURE SENSOR
Fig. 3 Pressure Tap Locations
Fig. 4 Line Pressure Adapter 8259
1 - LINE PRESSURE SENSOR PORT
2 - LINE PRESSURE SENSOR
3 - TOOL 8259
4 - PRESSURE TAP
WJAUTOMATIC TRANSMISSION - 545RFE 21 - 181
AUTOMATIC TRANSMISSION - 545RFE (Continued)

SPECIFICATIONS
TRANSMISSION
GENERAL
Component Metric Inch
Output Shaft End Play 0.22-0.55
mm0.009-0.021
in.
Input Shaft End Play 0.46-0.89
mm0.018-0.035
in.
2C Clutch Pack
Clearance0.455-1.335
mm0.018-0.053
in.
4C Clutch Pack
Clearance0.770-1.390
mm0.030-0.055
in.
L/R Clutch Pack
Clearance1.00-1.74
mm0.039-0.069
in.
OD Clutch Pack
Clearance1.103-1.856
mm0.043-0.073
in.
Component Metric Inch
UD Clutch Pack
Clearance0.84-1.54
mm0.033-0.061
in.
Reverse Clutch Pack
Clearance0.81-1.24
mm0.032-0.049
in.
Recommended fluid MoparTATF +4, type 9602
GEAR RATIOS
1ST 3.00:1
2ND 1.67:1
2ND Prime 1.50:1
3RD 1.0:1
4TH 0.75:1
5TH 0.67:1
REVERSE 3.00:1
TORQUE SPECIFICATIONS
DESCRIPTION N´m Ft. Lbs. In. Lbs.
Fitting, cooler line at trans 17.5 - 155
Bolt, torque convertor 31 23 -
Bolt/nut, crossmember 68 50 -
Bolt, driveplate to crankshaft 75 55 -
Bolt, oil pan 11.8 - 105
Screw, primary fluid filter 4.5 - 40
Bolt, oil pump 28.2 - 250
Bolt, oil pump body to cover 4.5 - 40
Screw, plate to oil pump body 4.5 - 40
Bolt, valve body to case 11.8 - 105
Plug, pressure test port 5.1 - 45
Bolt, reaction shaft support 11.8 - 105
Screw, valve body to transfer plate 5.6 - 50
Screw, solenoid module to transfer plate 5.7 - 50
Screw, accumulator cover 4.5 - 40
Screw, detent spring 4.5 - 40
Bolt, input speed sensor 11.8 - 105
Bolt, output speed sensor 11.8 - 105
Bolt, line pressure sensor 11.8 - 105
Bolt, extension housing 54 40 -
Valve, cooler return filter bypass 4.5 - 40
Screw, manual valve cam retaining 4.5 - 40
Bolt, manual lever 28.2 - 250
21 - 220 AUTOMATIC TRANSMISSION - 545RFEWJ
AUTOMATIC TRANSMISSION - 545RFE (Continued)

(9) Remove the oil pump valve retainers and asso-
ciated valve and spring one at a time (Fig. 93) (Fig.
94). Mark the combination of components as a group
and tag them as to the location from which they were
removed.
CLEANING
Clean pump and support components with solvent
and dry them with compressed air.
INSPECTION
Check condition of the seal rings and thrust
washer on the reaction shaft support. The seal rings
do not need to be replaced unless cracked, broken, or
severely worn.
Inspect the pump and support components. Replace
the pump or support if the seal ring grooves or
machined surfaces are worn, scored, pitted, or dam-
aged. Replace the pump gears if pitted, worn
chipped, or damaged.Inspect the pump reaction shaft support bushings.
Replace either bushing only if heavily worn, scored or
damaged. It is not necessary to replace the bushings
unless they are actually damaged.
Inspect the valves and plugs for scratches, burrs,
nicks, or scores. Minor surface scratches on steel
valves and plugs can be removed with crocus cloth
butdo not round off the edges of the valve or
plug lands.Maintaining sharpness of these edges is
vitally important. The edges prevent foreign matter
from lodging between the valves and plugs and the
bore.
Inspect all the valve and plug bores in the oil
pump cover. Use a penlight to view the bore interi-
ors. Replace the oil pump if any bores are distorted
or scored. Inspect all of the valve springs. The
springs must be free of distortion, warpage or broken
coils.
Trial fit each valve and plug in its bore to check
freedom of operation. When clean and dry, the valves
and plugs should drop freely into the bores.
Fig. 93 Oil Pump Valve Body
1 - T/C REGULATOR VALVE
2 - T/C LIMIT VALVE
3 - REGULATOR VALVE
4 - OIL PUMP VALVE BODY
Fig. 94 T/C Switch Valve
1 - RETAINER
2 - T/C SWITCH VALVE
3 - OIL PUMP VALVE BODY
21 - 252 AUTOMATIC TRANSMISSION - 545RFEWJ
OIL PUMP (Continued)

Inspect all the valve and plug bores in the valve
body. Use a penlight to view the bore interiors.
Replace the valve body if any bores are distorted or
scored. Inspect all of the valve body springs. The
springs must be free of distortion, warpage or broken
coils.
Trial fit each valve and plug in its bore to check
freedom of operation. When clean and dry, the valves
and plugs should drop freely into the bores.
Valve body bores do not change dimensionally with
use. If the valve body functioned correctly when new,
it will continue to operate properly after cleaning and
inspection. It should not be necessary to replace a
valve body assembly unless it is damaged in han-
dling.
Inspect all the accumulator bores in the valve body.
Use a penlight to view the bore interiors. Replace the
valve body if any bores are distorted or scored.Inspect all of the accumulator springs. The springs
must be free of distortion, warpage or broken coils.
Inspect all the fluid seals on the valve body (Fig.
133). Replace any seals that are cracked, distorted, or
damaged in any way. These seals pass fluid pressure
directly to the clutches. Any pressure leak at these
points, may cause transmission performance prob-
lems.
ASSEMBLY
(1) Lubricate valves, springs, and the housing
valve bores with clean transmission fluid.
(2) Install solenoid switch valve, manual valve,
and the low/reverse switch valve into the valve body.
(3) Install the retainers to hold each valve into the
valve body.
(4) Install the valve body check balls into their
proper locations.
(5) Position the transfer plate onto the valve body.
(6) Install the screws to hold the transfer plate to
the valve body. Tighten the screws to 5.6 N´m (50 in.
lbs.).
(7) Install the accumulator pistons and springs
into the valve body in the location from which they
were removed. Note that all accumulators except the
overdrive have two springs. The overdrive accumula-
tor piston has only one spring.
Fig. 132 Valve Body Components
1 - SOLENOID SWITCH VALVE
2 - MANUAL VALVE
3 - LOW REVERSE SWITCH VALVE
4 - LOW REVERSE ACCUMULATOR
5 - 2ND CLUTCH ACCUMULATOR
6 - UNDERDRIVE ACCUMULATOR
7 - OVERDRIVE ACCUMULATOR
8 - 4TH CLUTCH ACCUMULATOR
9 - CHECK BALLS (7)
Fig. 133 Valve Body Seals
1 - UNDERDRIVE ACCUMULATOR (2 SPRINGS)
2 - 4TH CLUTCH ACCUMULATOR (2 SPRINGS)
3 - 2ND CLUTCH ACCUMULATOR (2 SPRINGS)
4 - LOW REVERSE ACCUMULATOR (2 SPRINGS)
5 - LOW/REVERSE PASSAGE SEAL
6 - 2ND CLUTCH PASSAGE SEAL
7 - 4TH CLUTCH PASSAGE SEAL
8 - OVERDRIVE ACCUMULATOR (1 SPRING)
21 - 278 AUTOMATIC TRANSMISSION - 545RFEWJ
VALVE BODY (Continued)

REAR OUTPUT SHAFT/YOKE/DRIVE CHAIN
Check condition of the seal contact surfaces of the
yoke slinger (Fig. 49). This surface must be clean and
smooth to ensure proper seal life. Replace the yoke
nut and seal washer as neither part should be
reused.
Inspect the shaft threads, sprocket teeth, and bear-
ing surfaces. Minor nicks on the teeth can be
smoothed with an oilstone. Use 320-400 grit emery to
smooth minor scratches on the shaft bearing sur-
faces. Rough threads on the shaft can be chased if
necessary. Replace the shaft if the threads are dam-
aged, bearing surfaces are scored, or if any sprocket
teeth are cracked or broken.
Examine the drive chain and shaft bearings.
Replace the chain and both sprockets if the chain is
stretched, distorted, or if any of the links bind.
Replace the bearings if rough, or noisy.
LOW RANGE ANNULUS GEAR
Inspect annulus gear condition carefully. The gear
is only serviced as part of the front case. If the gear
is damaged, it will be necessary to replace the gear
and front case as an assembly. Do not attempt to
remove the gear (Fig. 50)
FRONT-REAR CASES AND FRONT RETAINER
Inspect the cases and retainer for wear and dam-
age. Clean the sealing surfaces with a scraper and
3M all purpose cleaner. This will ensure proper
sealer adhesion at assembly. Replace the input
retainer seal; do not reuse it.Check case condition. If leaks were a problem, look
for gouges and severe scoring of case sealing sur-
faces. Also make sure the front case mounting studs
are in good condition.
Check the front case mounting studs and vent
tube. The tube can be secured with LoctiteŸ 271 or
680 if loose. The stud threads can be cleaned up with
a die if necessary. Also check condition of the fill/
drain plug threads in the rear case. The threads can
be repaired with a thread chaser or tap if necessary.
Or the threads can be repaired with HelicoilŸ stain-
less steel inserts if required.
OIL PUMP/OIL PICKUP
Examine the oil pump pickup parts. Replace the
pump if any part appears to be worn or damaged. Do
not disassemble the pump as individual parts are not
available. The pump is only available as a complete
assembly. The pickup screen, hose, and tube are the
only serviceable parts and are available separately.
ASSEMBLY
Lubricate transfer case components with automatic
transmission fluid or petroleum jelly (where indi-
cated) during assembly.
CAUTION: The bearing bores in various transfer
case components contain oil feed holes. Make sure
replacement bearings do not block the holes.
Fig. 49 Seal Contact Surface Of Yoke Slinger
1 - FRONT SLINGER (PART OF YOKE)
2 - SEAL CONTACT SURFACE MUST BE CLEAN AND SMOOTH
Fig. 50 Low Range Annulus Gear
1 - FRONT CASE
2 - LOW RANGE ANNULUS GEAR
WJTRANSFER CASE - NV242 21 - 295
TRANSFER CASE - NV242 (Continued)

SPECIFICATIONS
TRANSFER CASE - NV242
TORQUE SPECIFICATIONS
DESCRIPTION N´m Ft. Lbs. In. Lbs.
Plug, Detent 16-24 11.8-17.7 -
Bolt, Diff. Case 17-27 12.5-19.9 -
Plug, Drain/Fill 20-34 15-25 -
Bolt, Front Brg. Retainer 16-27 11.8-19.9 -
Bolt, Case Half 35-46 25.8-33.9 -
Nut, Front Yoke 122-176 90-130 -
Screw, Oil Pump 1.2-1.8 - 12-15
Nut, Range Lever 27-34 19.9-25 -
Bolt, Rear Retainer 35-46 25.8-33.9 -
Nuts, Mounting 35 25.8 -
Bolts, U-Joint 19 14 -
SPECIAL TOOLS
TRANSFER CASE - NV242
Installer, Seal - C-4076-B
Handle, Universal - C-4171
Remover, Bearing - C-4210
Puller, Slinger - MD-998056-A
Installer - MD-998323
Installer, Bearing - 5064
21 - 308 TRANSFER CASE - NV242WJ
TRANSFER CASE - NV242 (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)

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)

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)

open circuit to the fuse in the junction block as
required.
(5) The coil ground terminal cavity (85) is switched
to ground through the Powertrain Control Module
(PCM). There should be continuity between this cav-
ity and the A/C compressor clutch relay control cir-
cuit cavity of the PCM wire harness connector C
(gray) at all times. If not OK, repair the open circuit
as required.
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the cover from the Power Distribution
Center (PDC) (Fig. 11).
(3) Refer to the label on the PDC for compressor
clutch relay identification and location.
(4) Unplug the compressor clutch relay from the
PDC.
INSTALLATION
(1) Install the compressor clutch relay by aligning
the relay terminals with the cavities in the PDC and
pushing the relay firmly into place.
(2) Install the PDC cover.
(3) Connect the battery negative cable.
(4) Test the relay operation.
A/C HEATER CONTROL
DESCRIPTION
The manual temperature control HVAC system
uses a combination of electrical, and vacuum con-trols. The Automatic Zone Control (AZC) HVAC sys-
tem uses only electrical controls. These controls
provide the vehicle operator with a number of setting
options to help control the climate and comfort
within the vehicle. Refer to the owner's manual in
the vehicle glove box for more information on the
suggested operation and use of these controls.
Both a/c heater control panels are located on the
instrument panel inboard of the steering column and
below the radio (Fig. 12). Both control panels contain
rotary-type temperature control knob(s), a rotary-
type mode control switch knob, a rotary-type blower
motor speed switch knob and an air conditioning
compressor push button switch. The rear window
defogger push button switch is also located on a/c
heater control panel. The AZC control panel also fea-
tures a recirculation push button switch and a vac-
uum fluorescent display area.
OPERATION
The AZC control module uses infrared sensing
technology to control occupant comfort levels, not the
actual passenger compartment air temperature. Dual
infrared sensors mounted in the face of the control
unit independently measure the surface temperature
to maintain customer-perceived comfort temperature
under changing conditions. Dual Zone temperature
control provides wide side-to-side variation in comfort
temperature to exceed the needs of either front seat
occupant. This sensing system replaces interior air
temperature and solar sensors used to approximate
direct sensing control through complex control pro-
grams.
Fig. 11 POWER DISTRIBUTION CENTER (PDC)
1 - TRANSMISSION CONTROL MODULE (TCM)
2 - NEGATIVE CABLE
3 - POSITIVE CABLE
4 - POWER DISTRIBUTION CENTER (PDC)
Fig. 12 A/C HEATER CONTROL PANELS
WJCONTROLS 24 - 17
A/C COMPRESSOR CLUTCH RELAY (Continued)