Ac system JEEP GRAND CHEROKEE 2002 WJ / 2.G Workshop Manual

GEAR
TABLE OF CONTENTS
page page
GEAR
DESCRIPTION.........................16
OPERATION...........................16
REMOVAL.............................16
INSTALLATION.........................16
ADJUSTMENTS
STEERING GEAR.....................18
SPECIFICATIONS
POWER STEERING GEAR..............18
SPECIAL TOOLS
POWER STEERING GEAR..............19
PITMAN SHAFT
REMOVAL.............................20INSTALLATION.........................20
PITMAN SHAFT BEARING
REMOVAL.............................22
INSTALLATION.........................22
PITMAN SHAFT SEAL
REMOVAL.............................22
INSTALLATION.........................23
RACK PISTON/VALVE ASSEMBLY
REMOVAL.............................23
INSTALLATION.........................25
STUB SHAFT HOUSING
REMOVAL.............................25
INSTALLATION.........................25
GEAR
DESCRIPTION
The power steering gear is a recirculating ball type
gear (Fig. 1) .
The following gear components can be serviced:
²Pitman Shaft and Cover
²Pitman Shaft Bearings
²Pitman Shaft Oil Seal/Dust Seal
²Stud Shaft Housing with Seal
²O-Rings and Teflon Rings
NOTE: If rack piston assembly is damaged the gear
must be replaced.
OPERATION
The gear acts as a rolling thread between the
worm shaft and rack piston. The worm shaft is sup-
ported by a thrust bearing at the lower end and a
bearing assembly at the upper end. When the worm
shaft is turned the rack piston moves. The rack pis-
ton teeth mesh with the pitman shaft. Turning the
worm shaft turns the pitman shaft, which turns the
steering linkage.
REMOVAL
(1) Place the front wheels in the straight ahead
position with the steering wheel centered and locked.
(2) Remove the air cleaner housing,(Refer to 9 -
ENGINE/AIR INTAKE SYSTEM/AIR CLEANER
HOUSING - REMOVAL).
(3) Drain or siphon the power steering system.(4) Remove the pressure and return lines (Fig.
2)from the steering gear. Refer to hose removal in
this section.
(5) Remove the column coupler shaft bolt (Fig.
2)and remove the shaft from the gear.
(6) Raise and support the vehicle.
(7) Remove the left front wheel and tire assembly.
(8) Remove the pitman arm from gear with Puller
C-4150A.
(9) Remove the windshield washer reservoir,(Refer
to 8 - ELECTRICAL/WIPERS/WASHERS/WASHER
RESERVOIR - REMOVAL).
(10) Remove the steering gear mounting bolts.
Remove the steering gear out of the engine compart-
ment (Fig. 3).
INSTALLATION
(1) Position the steering gear on the frame rail and
install the bolts. Tighten the bolts to 108 N´m (80 ft.
lbs.) torque.
(2) Install the pitman arm and tighten nut to 251
N´m (185 ft. lbs.).
(3) Install windshield washer reservoir,(Refer to 8 -
ELECTRICAL/WIPERS/WASHERS/WASHER RES-
ERVOIR - INSTALLATION).
(4) Install the wheel and tire assembly.
(5) Remove the support and lower the vehicle.
(6) Install the pressure and return hoses to the
steering gear and tighten to 20-38 N´m (14-28 ft.
lbs.).
(7) Install the column coupler shaft.
(8) Install the air cleaner housing,(Refer to 9 -
ENGINE/AIR INTAKE SYSTEM/AIR CLEANER
HOUSING - INSTALLATION).
19 - 16 GEARWJ

SPECIFICATIONS
TORQUE CHART
TORQUE SPECIFICATIONS
DESCRIPTION N´m Ft. Lbs. In. Lbs.
Pitman Arm
Shaft Nut251 185 Ð
Drag Link
Pitman Arm Nut88 65 Ð
Drag Link
Knuckle Nut47 35 Ð
Drag Link
Clamp Nuts41 30 Ð
Tie Rod
Knuckle Nut47 35 Ð
Tie Rod
Clamp Nuts41 30 Ð
Steering Damper
Axle Bolt88 65 Ð
Steering Damper
Tie Rod Nut41 30 Ð
SPECIAL TOOLS
STEERING LINKAGEDAMPER
DESCRIPTION
The damper is mounted to the axle housing and
the tie rod end. The damper consists of steel tube
shock absorber with a permanent bushed end.
OPERATION
The steering damper provides steering system
damping.
REMOVAL
(1) Remove the nut from the ball stud at the tie
rod.
(2) Remove the steering damper from the tie rod.
(3) Remove the steering damper nut and bolt from
the axle bracket (Fig. 3) .Puller C-3894±A
Remover Pitman C-4150A
19 - 28 LINKAGEWJ
LINKAGE (Continued)

PUMP
DESCRIPTION - 4.0L, 4.7L
Hydraulic pressure for the power steering system
is provided by a belt driven power steering pump
(Fig. 1) and (Fig. 2). The pump shaft has a
pressed-on drive pulley that is belt driven by the
crankshaft pulley.
OPERATION
OPERATION - 4.7L
The power steering pump is a constant flow rate
and displacement, vane-type pump. The pump has
internal parts that operate submerged in fluid. The
flow control orifice and the pressure relief valve,
which limits the pump pressure, are internal to the
pump. The reservoir is attached to the pump body
with spring clips. The power steering pump is used
to drive the hydraulic engine cooling fan, which sep-
arates the flow to the fan gerotors and the power
steering gear. The power steering pump is connected
to the engine cooling fan by pressure and return
hoses and the pump is connected to the steering gear
via a return hose from the steering cooler (Fig. 2).NOTE: Power steering pumps have different pres-
sure rates and are not interchangeable with other
pumps.OPERATION - 4.0L
The power steering pump is a constant flow rate
and displacement, vane-type pump. The pump inter-
nal parts operate submerged in fluid. The flow con-
trol orifice is part of the high pressure line fitting.
The pressure relief valve inside the flow control valve
limits the pump pressure. The reservoir is attached
to the pump body with spring clips. The power steer-
ing pump is connected to the steering gear by the
pressure and return hoses (Fig. 1).
NOTE: Power steering pumps have different pres-
sure rates and are not interchangeable with other
pumps.
Fig. 1 Pump With Integral Reservoir
1 - CAP
2 - FLUID RESERVOIR (TYPICAL)
3 - HIGH-PRESSURE FITTING
4 - DRIVE PULLEY
5 - PUMP BODY
6 - RESERVOIR CLIP
Fig. 2 4.7L POWER STEERING PUMP
1 - PRESSURE HOSE QUICK CONNECT NUT
2 - CAP
3 - FLUID RESERVOIR
4 - LOW-PRESSURE RETURN FROM THE COOLER
5 - LOW-PRESSURE RETURN FROM THE HYDRAULIC FAN
DRIVE
6 - PUMP BODY
7 - HIGH PRESSURE FITTING
19 - 32 PUMPWJ

DIAGNOSIS AND TESTING - PUMP LEAKAGE
(1) Possible areas of pump leakage (Fig. 3).
STANDARD PROCEDURE
STANDARD PROCEDURE - INITIAL OPERATION
- 4.0L
WARNING: THE FLUID LEVEL SHOULD BE
CHECKED WITH ENGINE OFF TO PREVENT INJURY
FROM MOVING COMPONENTS.
CAUTION: Use MOPAR Power Steering Fluid or
equivalent. Do not use automatic transmission fluid
and do not overfill.
Wipe filler cap clean, then check the fluid level.
The dipstick should indicateCOLDwhen the fluid is
at normal ambient temperature.
(1) Fill the pump fluid reservoir to the proper level
and let the fluid settle for at least two minutes.
(2) Start the engine and let run for a few seconds
then turn engine off.
(3) Add fluid if necessary. Repeat the above proce-
dure until the fluid level remains constant after run-
ning the engine.
(4) Raise the front wheels off the ground.
(5) Slowly turn the steering wheel right and left,
lightly contacting the wheel stops at least 20 times.(6) Check the fluid level add if necessary.
(7) Lower the vehicle, start the engine and turn
the steering wheel slowly from lock to lock.
(8) Stop the engine and check the fluid level and
refill as required.
(9) If the fluid is extremely foamy or milky look-
ing, allow the vehicle to stand a few minutes and
repeat the procedure.
CAUTION: Do not run a vehicle with foamy fluid for
an extended period. This may cause pump damage.
STANDARD PROCEDURE - INITIAL OPERATION
- 4.7L
WARNING: THE FLUID LEVEL SHOULD BE
CHECKED WITH ENGINE OFF TO PREVENT INJURY
FROM MOVING COMPONENTS.
NOTE: Remove as much of the old fluid out of the
system as possible with a suction tool or by remov-
ing a hose, When a component has failed. Then
refill it with fresh fluid until it is clean. This may
have to be done more than once.
CAUTION: Use MOPAR Power Steering Fluid or
equivalent. Do not use automatic transmission fluid
and do not overfill.
Wipe filler cap clean, then check the fluid level.
The dipstick should indicateCOLDwhen the fluid is
at normal ambient temperature.
(1) Fill the pump fluid reservoir to the proper level
and let the fluid settle for at least two minutes.
(2) Start the engine and let run for a few seconds
then turn engine off.
(3) Add fluid if necessary. Repeat the above proce-
dure until the fluid level remains constant after run-
ning the engine.
(4) Raise the front wheels off the ground.
(5) Slowly turn the steering wheel right and left,
lightly contacting the wheel stops at least 20 times.
(6) Check the fluid level add if necessary.
(7) Lower the vehicle, start the engine, and use
the DRB III to activate the hydraulic fan on full fan
operation.
(8)
Turn the steering wheel slowly from lock to lock.
(9) Stop the engine, check the fluid level and refill
as required and repeat the process
CAUTION: Do not run a vehicle with foamy fluid for
an extended period. This may cause pump damage.
(10) If the fluid is extremely foamy or milky look-
ing, allow the vehicle to stand a few minutes and
repeat the procedure.
Fig. 3 4.0L Power Steering Pump
WJPUMP 19 - 33
PUMP (Continued)

SPECIAL TOOLS
POWER STEERING PUMP
FLUID COOLER
DESCRIPTION
4.7L models of this vehicle are equipped with a
cooler for the power steering system fluid. The power
steering fluid cooler is located at the front of the
vehicle. It is mounted to the radiator support just
forward of the air-conditioning condenser and just
rearward of the front fascia (Fig. 6). The cooler is
positioned so it is in the air flow through the front
fascia of the vehicle.
REMOVAL
(1) Disconnect negative battery cable at battery.
(2) Drain the power steering fluid out of the reser-
voir.
(3) Remove the front fascia grille assembly,(Refer
to 13 - FRAMES & BUMPERS/BUMPERS/FRONT
FASCIA - REMOVAL).
(4) Remove the grille opening reinforcement panel
(5) Place a drain pan under the cooler.
(6) Disconnect the lower hose at cooler (Fig. 6).
(7) Disconnect the upper hose at cooler (Fig. 6).
(8) Remove the three cooler mounting bolts (Fig.
6).
(9) Remove the cooler from the vehicle.
Analyzer Set, Power Steering Flow/Pressure 6815
Adapters, Power Steering Flow/Pressure Tester
6893
4.7L HYDRAULIC POWER STEERING TEST
ADAPTER KIT - 8630
Puller C-4333
Installer, Power Steering Pulley C-4063B
Fig. 6 POWER STEERING FLUID COOLER
1 - POWER STEERING COOLER
2 - POWER STEERING COOLER LINES CLIP
19 - 36 PUMPWJ
PUMP (Continued)

INSTALLATION
(1) Position and install the power steering cooler
to the vehicle.
(2) Install the three mounting bracket bolts (Fig.
6).
(3) Reconnect the upper hose at cooler (Fig. 6).
(4) Reconnect the lower hose at cooler (Fig. 6).
(5) Connect negative battery cable to battery.
(6) Refill the power steering fluid and bleed the
system,(Refer to 19 - STEERING/PUMP - STAN-
DARD PROCEDURE).
(7) Start engine and check for leaks.
(8) Install the grille opening reinforcement panel
(9) Install the front fascia grille,(Refer to 13 -
FRAMES & BUMPERS/BUMPERS/FRONT FASCIA
- INSTALLATION).
HOSES - 4.0L
DESCRIPTION
DESCRIPTION - PRESSURE LINE
The hose consists of two metal ends and rubber
center section that contains a tuning cable. The
pump end uses a quick connect fitting. Lubircation
must be used on the quick connect nut and o-ring
when installing.
DESCRIPTION - RETURN LINE
Power steering return line is a hose which is
clamped at the pump and the gear.
OPERATION
OPERATION - PRESSURE LINE
Power steering pressure line, is used to transfer
high pressure power steering fluid, from the power
steering pump to the power steering gear on the
4.0L. The 4.7L power steering pressure line, is used
to transfer high pressure power steering fluid, from
the power steering pump to the engine cooling fan
and the steering gear.
OPERATION - RETURN LINE
Power steering return line, is used to transfer low
pressure power steering fluid, from the power steer-
ing gear to the power steering pump.
REMOVAL
(1) Drain the power steering fluid from the reser-
voir.
(2) Remove the air box,(Refer to 9 - ENGINE/AIR
INTAKE SYSTEM/AIR CLEANER HOUSING -
REMOVAL).
(3) Disconnect the power steering pressure hose
from the power steering pump and then the power
steering gear (Fig. 7).
(4) Disconnect the power steering return hose from
the power steering cooler and the reservoir.
(5) Remove the hoses from the vehicle.
INSTALLATION
(1) Install the hoses to the vehicle.
(2) Reconnect the power steering return hose to
the power steering cooler and the reservoir.
(3) Reconnect the power steering pressure hose to
the power steering pump and then the power steer-
ing gear.
(4) Install the air box,(Refer to 9 - ENGINE/AIR
INTAKE SYSTEM/AIR CLEANER HOUSING -
INSTALLATION).
(5) Refill the power steering fluid and bleed the
system,(Refer to 19 - STEERING/PUMP - STAN-
DARD PROCEDURE).
Fig. 7 POWER STEERING HOSES
1 - RETURN HOSE
2 - HIGH PRESSURE HOSE
3 - STEERING GEAR
WJPUMP 19 - 37
FLUID COOLER (Continued)

OPERATION - 3/8º PRESSURE HOSE
High pressure power steering fluid is transmitted
from the hydraulic fan motor to the steering gear by
the 3/8º steering line.
OPERATION - 3/8º GEAR OUTLET HOSE
The gear outlet hose transmits power steering fluid
under moderate low pressure to the power steering
cooler inlet tube.
OPERATION - 3/8ºRETURN HOSE
Low pressure power steering fluid is transmitted
from the steering cooler back to the power steering
pump by the 3/8º return hose.
REMOVAL
REMOVAL - 1/2(PRESSURE HOSE
(1)Drain the power steering fluid from the reservoir.
(2) Remove the air box,(Refer to 9 - ENGINE/AIR
INTAKE SYSTEM/AIR CLEANER HOUSING -
REMOVAL).
(3) Raise and support the vehicle.
(4) Remove the metal skid plate.
(5) Disconnect the high pressure hose from the
hydraulic fan motor (Fig. 8).
(6) Disconnect the high pressure hose from the
power steering pump (Fig. 8).
(7) Remove the hose from the clipped position on
the fan shroud.
(8) Remove the hose from the vehicle.
REMOVAL - 1/2(RETURN HOSE
(1) Drain the power steering fluid from the reser-
voir.
(2) Remove the air box,(Refer to 9 - ENGINE/AIR
INTAKE SYSTEM/AIR CLEANER HOUSING -
REMOVAL).
(3) Raise and support the vehicle.
(4) Remove the metal skid plate.
(5) Disconnect the rubber return hose from the
hydraulic fan motor (Fig. 9).
(6) Disconnect the rubber return hose from the
power steering reservoir .
(7) Remove the hose from the vehicle.
REMOVAL - 3/8(PRESSURE HOSE
(1) Drain the power steering fluid from the reser-
voir.
(2) Remove the air box,(Refer to 9 - ENGINE/AIR
INTAKE SYSTEM/AIR CLEANER HOUSING -
REMOVAL).
(3) Raise and support the vehicle.
(4) Remove the metal skid plate.
(5) Disconnect the high pressure hose from the
hydraulic fan motor (Fig. 10).
(6) Disconnect the high pressure hose from the
power steering gear (Fig. 10).
(7) Remove the hose from the clipped position on
the fan shroud.
(8) Remove the hose from the vehicle.
REMOVAL - 3/8(RETURN HOSE
(1) Drain the power steering fluid from the reser-
voir.
(2) Remove the air box,(Refer to 9 - ENGINE/AIR
INTAKE SYSTEM/AIR CLEANER HOUSING -
REMOVAL).
(3) Raise and support the vehicle.
(4) Disconnect the rubber hose from the steering
cooler outlet tube (Fig. 12).
Fig. 11 3/8(GEAR OUTLET HOSE
1 - HOSE CLAMP
2 - 3/89GEARR OUTLET HOSE
Fig. 12 3/8(RETURN HOSE
1 - HOSE CLAMP
2 - 3/89RETURN HOSE
3 - HYDRAULIC COOLING FAN MOTOR
WJPUMP 19 - 39
HOSES - 4.7L (Continued)

(5) Disconnect the rubber hose from the power
steering reservoir (Fig. 12).
(6) Remove the hose from the vehicle.
REMOVAL - 3/8(GEAR OUTLET HOSE
(1) Drain the power steering fluid from the reser-
voir.
(2) Remove the air box,(Refer to 9 - ENGINE/AIR
INTAKE SYSTEM/AIR CLEANER HOUSING -
REMOVAL).
(3) Raise and support the vehicle.
(4) Disconnect the rubber hose from the steering
cooler inlet tube (Fig. 11).
(5) Disconnect the metal tube from the power
steering gear (Fig. 11).
(6) Remove the hose from the vehicle.
REMOVAL - INLET COOLER HOSE
(1) Disconnect negative battery cable at battery.
(2) Drain the power steering fluid out of the reser-
voir.
(3) Remove the air box,(Refer to 9 - ENGINE/AIR
INTAKE SYSTEM/AIR CLEANER HOUSING -
REMOVAL).
(4) Remove the front fascia grille assembly,(Refer
to 13 - FRAMES & BUMPERS/BUMPERS/FRONT
FASCIA - REMOVAL).
(5) Remove the grille opening reinforcement panel
(6) Place a drain pan under the cooler.
(7) Disconnect the lower hose at cooler (Fig. 6).
(8) Disconnect the cooler hose at the gear.
(9) Remove the bracket holding the cooler hoses
(Fig. 13).
(10) Remove the cooler hose from the vehicle.
REMOVAL - OUTLET COOLER HOSE
(1) Disconnect negative battery cable at battery.
(2) Drain the power steering fluid out of the reser-
voir.
(3) Remove the air box,(Refer to 9 - ENGINE/AIR
INTAKE SYSTEM/AIR CLEANER HOUSING -
REMOVAL).
(4) Remove the front fascia grille assembly,(Refer
to 13 - FRAMES & BUMPERS/BUMPERS/FRONT
FASCIA - REMOVAL).
(5) Remove the grille opening reinforcement panel
(6) Place a drain pan under the cooler.
(7) Disconnect the upper hose at cooler (Fig. 6).
(8) Disconnect the cooler hose at the reservoir.
(9) Remove the bracket holding the cooler hoses
(Fig. 13).
(10) Remove the cooler hose from the vehicle.
INSTALLATION
INSTALLATION - 1/2(PRESSURE HOSE
NOTE: Lubrication and a new o-ring must be used
when reinstalling.
(1) Install the hoses to the vehicle.
(2) Reconnect the high pressure hose to the power
steering pump (Fig. 8) Tighten the hose to 22.5 N´m
(17 ft.lbs.).
(3) Reconnect the high pressure hose to the
hydraulic fan motor (Fig. 8) Tighten the hose to 22.5
N´m (17 ft.lbs.).
(4) Install the hose to the clipped position on the
fan shroud.
(5) Install the metal skid plate.
(6) Install the air box,(Refer to 9 - ENGINE/AIR
INTAKE SYSTEM/AIR CLEANER HOUSING -
INSTALLATION).
(7) Refill the power steering fluid and bleed the
system,(Refer to 19 - STEERING/PUMP - STAN-
DARD PROCEDURE).
INSTALLATION - 1/2(RETURN HOSE
(1) Install the hoses to the vehicle.
(2) Reconnect the rubber return hose to the power
steering reservoir (Fig. 9) Tighten the hose clamp.
(3) Reconnect the rubber return hose to the
hydraulic fan motor (Fig. 9) Tighten the hose.
(4) Install the metal skid plate.
(5) Install the air box,(Refer to 9 - ENGINE/AIR
INTAKE SYSTEM/AIR CLEANER HOUSING -
INSTALLATION).
(6) Refill the power steering fluid and bleed the
system,(Refer to 19 - STEERING/PUMP - STAN-
DARD PROCEDURE).
Fig. 13 COOLER HOSES MOUNTING BRACKET
1 - RADIATOR
2 - COOLER HOSES MOUNTING BRACKET
2 - COOLER HOSE
19 - 40 PUMPWJ
HOSES - 4.7L (Continued)

INSTALLATION - 3/8(PRESSURE HOSE
NOTE: Lubrication and a new o-ring must be used
when reinstalling.
(1) Install the hoses to the vehicle.
(2) Reconnect the high pressure hose to the
hydraulic fan motor (Fig. 10) Tighten the hose to
22.5 N´m (17 ft.lbs.).
(3) Reconnect the high pressure hose to the power
steering gear (Fig. 10) Tighten the hose to 22.5 N´m
(17 ft.lbs.).
(4) Install the hose to the clipped position on the
fan shroud.
(5) Install the metal skid plate.
(6) Install the air box,(Refer to 9 - ENGINE/AIR
INTAKE SYSTEM/AIR CLEANER HOUSING -
INSTALLATION).
(7) Refill the power steering fluid and bleed the
system,(Refer to 19 - STEERING/PUMP - STAN-
DARD PROCEDURE).
INSTALLATION - 3/8(RETURN HOSE
(1) Install the hoses to the vehicle.
(2) Reconnect the rubber hose to the steering
cooler outlet tube (Fig. 12) Tighten the hose clamp.
(3) Reconnect the rubber hose to the power steer-
ing reservoir (Fig. 12) Tighten the hose clamp.
(4) Install the air box,(Refer to 9 - ENGINE/AIR
INTAKE SYSTEM/AIR CLEANER HOUSING -
INSTALLATION).
(5) Refill the power steering fluid and bleed the
system,(Refer to 19 - STEERING/PUMP - STAN-
DARD PROCEDURE).
INSTALLATION - 3/8(GEAR OUTLET HOSE
NOTE: Lubrication and a new o-ring must be used
when reinstalling.
(1) Install the hoses to the vehicle.
(2) Reconnect the rubber hose to the steering
cooler inlet tube (Fig. 11) Tighten the hose clamp.
(3)
Reconnect the metal tube to the power steering
gear (Fig. 11) Tighten the hose to 22.5 N´m (17 ft.lbs.).
(4) Install the air box,(Refer to 9 - ENGINE/AIR
INTAKE SYSTEM/AIR CLEANER HOUSING -
INSTALLATION).
(5) Refill the power steering fluid and bleed the
system,(Refer to 19 - STEERING/PUMP - STAN-
DARD PROCEDURE).
INSTALLATION - INLET COOLER HOSE
(1) Install the cooler hose to the vehicle.
(2) Reconnect the cooler hose at the gear.
(3) Reconnect the lower hose at cooler (Fig. 6).
Tighten the hose to 22.5 N´m (17 ft.lbs.)
(4) Install the bracket holding the cooler hoses
(Fig. 13).(5) Install the air box,(Refer to 9 - ENGINE/AIR
INTAKE SYSTEM/AIR CLEANER HOUSING -
INSTALLATION).
(6) Install the grille opening reinforcement panel
(7) Install the front fascia grille assembly, (Refer to
13 - FRAMES & BUMPERS/BUMPERS/FRONT
FASCIA - INSTALLATION).
(8) Reconnect negative battery cable at battery.
(9) Refill the power steering fluid and bleed the
system,(Refer to 19 - STEERING/PUMP - STAN-
DARD PROCEDURE).
INSTALLATION - OUTLET COOLER HOSE
(1) Install the cooler hose to the vehicle.
(2) Reconnect the cooler hose at the reservoir.
(3) Reconnect the upper hose at the cooler (Fig. 6).
Tighten the hose to 22.5 N´m (17 ft. lbs.)
(4) Install the bracket holding the cooler hoses
(Fig. 13). Tighten the bracket to 22.5 N´m (17 ft. lbs.)
(5) Install the air box,(Refer to 9 - ENGINE/AIR
INTAKE SYSTEM/AIR CLEANER HOUSING -
INSTALLATION).
(6) Install the grille opening reinforcement panel
(7) Install the front fascia grille assembly, (Refer to
13 - FRAMES & BUMPERS/BUMPERS/FRONT
FASCIA - INSTALLATION).
(8) Reconnect negative battery cable at battery.
(9) Refill the power steering fluid and bleed the
system,(Refer to 19 - STEERING/PUMP - STAN-
DARD PROCEDURE).
PULLEY
DESCRIPTION
POWER STEERING PUMP PULLEY - 3.1L
DIESEL
To service the power steering pump pulley on the
3.1L turbo diesel engine. Refer to the power steering
pump removal and installation procedure in this
group. The pulley must be removed to service the
pump assembly. Detailed instructions are provided in
the pump procedure.
REMOVAL
CAUTION: On vehicles equipped with the 4.0L or
4.7L, Do not reuse the old power steering pump
pulley it is not intended for reuse. A new pulley
must be installed if removed.
(1) Remove pump assembly.
(2) Remove pulley from pump with Puller C-4333
or equivalent puller (Fig. 14).
WJPUMP 19 - 41
HOSES - 4.7L (Continued)

FOURTH GEAR POWERFLOW
Fourth gear overdrive range is electronically con-
trolled and hydraulically activated. Various sensor
inputs are supplied to the powertrain control module
to operate the overdrive solenoid on the valve body.
The solenoid contains a check ball that opens and
closes a vent port in the 3-4 shift valve feed passage.
The overdrive solenoid (and check ball) are not ener-
gized in first, second, third, or reverse gear. The vent
port remains open, diverting line pressure from the
2-3 shift valve away from the 3-4 shift valve. The
overdrive control switch must be in the ON position
to transmit overdrive status to the PCM. A 3-4
upshift occurs only when the overdrive solenoid is
energized by the PCM. The PCM energizes the over-
drive solenoid during the 3-4 upshift. This causes the
solenoid check ball to close the vent port allowing
line pressure from the 2-3 shift valve to act directly
on the 3-4 upshift valve. Line pressure on the 3-4
shift valve overcomes valve spring pressure moving
the valve to the upshift position. This action exposes
the feed passages to the 3-4 timing valve, 3-4 quick
fill valve, 3-4 accumulator, and ultimately to the
overdrive piston. Line pressure through the timing
valve moves the overdrive piston into contact with
the overdrive clutch. The direct clutch is disengaged
before the overdrive clutch is engaged. The boost
valve provides increased fluid apply pressure to the
overdrive clutch during 3-4 upshifts, and when accel-
erating in fourth gear. The 3-4 accumulator cushions
overdrive clutch engagement to smooth 3-4 upshifts.
The accumulator is charged at the same time as
apply pressure acts against the overdrive piston.
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - AUTOMATIC
TRANSMISSION
Automatic transmission problems can be a result of
poor engine performance, incorrect fluid level, incor-
rect linkage or cable adjustment, band or hydraulic
control pressure adjustments, hydraulic system mal-
functions or electrical/mechanical component mal-
functions. Begin diagnosis by checking the easily
accessible items such as: fluid level and condition,
linkage adjustments and electrical connections. A
road test will determine if further diagnosis is neces-
sary.
DIAGNOSIS AND TESTING - PRELIMINARY
Two basic procedures are required. One procedure
for vehicles that are drivable and an alternate proce-
dure for disabled vehicles (will not back up or move
forward).
VEHICLE IS DRIVEABLE
(1) Check for transmission fault codes using DRBt
scan tool.
(2) Check fluid level and condition.
(3) Adjust throttle and gearshift linkage if com-
plaint was based on delayed, erratic, or harsh shifts.
(4) Road test and note how transmission upshifts,
downshifts, and engages.
(5) Perform hydraulic pressure test if shift prob-
lems were noted during road test.
(6) Perform air-pressure test to check clutch-band
operation.
VEHICLE IS DISABLED
(1) Check fluid level and condition.
(2) Check for broken or disconnected gearshift or
throttle linkage.
(3) Check for cracked, leaking cooler lines, or loose
or missing pressure-port plugs.
(4) Raise and support vehicle on safety stands,
start engine, shift transmission into gear, and note
following:
(a) If propeller shaft turns but wheels do not,
problem is with differential or axle shafts.
(b) If propeller shaft does not turn and transmis-
sion is noisy, stop engine. Remove oil pan, and
check for debris. If pan is clear, remove transmis-
sion and check for damaged drive plate, converter,
oil pump, or input shaft.
(c) If propeller shaft does not turn and transmis-
sion is not noisy, perform hydraulic-pressure test to
determine if problem is hydraulic or mechanical.
DIAGNOSIS AND TESTING - ROAD TESTING
Before road testing, be sure the fluid level and con-
trol cable adjustments have been checked and
adjusted if necessary. Verify that diagnostic trouble
codes have been resolved.
Observe engine performance during the road test.
A poorly tuned engine will not allow accurate analy-
sis of transmission operation.
Operate the transmission in all gear ranges. Check
for shift variations and engine flare which indicates
slippage. Note if shifts are harsh, spongy, delayed,
early, or if part throttle downshifts are sensitive.
Slippage indicated by engine flare, usually means
clutch, band or overrunning clutch problems. If the
condition is advanced, an overhaul will be necessary
to restore normal operation.
A slipping clutch or band can often be determined
by comparing which internal units are applied in the
various gear ranges. The Clutch and Band Applica-
tion chart provides a basis for analyzing road test
results.
WJAUTOMATIC TRANSMISSION - 42RE 21 - 11
AUTOMATIC TRANSMISSION - 42RE (Continued)