2002 JEEP GRAND CHEROKEE Power steering

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

(9) Fill the power steering pump (Refer to 19 -
STEERING/PUMP - STANDARD PROCEDURE).
Fig. 1 Recirculating Ball Type Gear
1 - ADJUSTER NUT
2 - COVER
3 - PITMAN SHAFT
4 - O-RING
5 - BEARING
6 - GEAR HOUSING
7 - RACK PISTON
8 - RETAINING RING
9 - O-RING
10 - BEARING
11 - STUB SHAFT HOUSING
12 - PITMAN SHAFT SEAL
13 - PLASTIC BACKUP WASHER
14 - METAL BACKUP WASHER
15 - RETAINING RING
16 - DUST SEAL
Fig. 2 Pressure And Return Lines
1 - PRESSURE LINE
2 - RETURN LINE
3 - COUPLER BOLT
4 - STEERING GEAR
Fig. 3 Steering Gear Mounting
1 - MOUNTING BOLTS
2 - PITMAN SHAFT
3 - STABILIZER BAR
WJGEAR 19 - 17
GEAR (Continued)

ADJUSTMENTS
STEERING GEAR
NOTE: Adjusting the steering gear in the vehicle is
not recommended. Remove gear from the vehicle
and drain the fluid. Then mount gear in a vise to
perform adjustments.
OVER-CENTER
(1) Rotate the stub shaft with Socket 8343 from
stop to stop and count the number of turns.
(2) Center the stub shaft by rotating it from the
stop 1/2 of the total amount of turns.
(3) Place torque wrench and Socket 8343 in a ver-
tical position on the stub shaft. Rotate the wrench 45
degrees each side of the center and record the high-
est rotational torque in this range (Fig. 4) . This is
the Over-Center Rotating Torque.
NOTE: The stub shaft must rotate smoothly without
sticking or binding.
(4) Rotate the stub shaft between 90É and 180É to
the left of center and record the left off-center pre-
load. Repeat this to the right of center and record the
right off-center preload. The average of these two
recorded readings is the Preload Rotating Torque.
(5) The Over-Center Rotating Torque should be
0.45-0.80 N´m (4-7 in. lbs.)higherthan the Preload
Rotating Torque.
(6) If an adjustment to the Over-Center Rotating
Torque is necessary, first loosen the adjuster lock
nut. Then turn the pitman shaft adjuster screw back
(COUNTERCLOCKWISE) until fully extended, then
turn back in (CLOCKWISE) one full turn.
(7) Remeasure Over-Center Rotating Torque. If
necessary turn the adjuster screw and repeat mea-
surement until correct Over-Center Rotating Torque
is reached.
NOTE: To increase the Over-Center Rotating Torque
turn the screw CLOCKWISE.(8) Prevent the adjuster screw from turning while
tightening adjuster lock nut. Tighten the adjuster
lock nut to 37-52 N´m (27-38 ft. lbs.).
SPECIFICATIONS
POWER STEERING GEAR
SPECIFICATIONS
DESCRIPTION SPECIFICATION
Steering Gear
TypeRecirculating Ball
Steering Gear
Overall Ratio12.7:1
TORQUE SPECIFICATIONS
DESCRIPTION N´m Ft. Lbs. In. Lbs.
Pitman Shaft Overcenter Drag
New Gear (under 400 miles)0.45-0.80
+ Worm Shaft PreloadÐ 4-7
+ Worm Shaft Preload
Pitman Shaft Overcenter Drag
Used Gear (over 400 miles)0.5-0.6
+ Worm Shaft PreloadÐ 4-5
+ Worm Shaft Preload
Fig. 4 Checking Over-center Rotation Torque
1 - CENTER
19 - 18 GEARWJ
GEAR (Continued)

SPECIAL TOOLS
POWER STEERING GEAR
Puller Seal 7794-A
Slide Hammer C-637
Remover, Pitman Arm C-4150A
Handle C-4171
Driver 8277
Driver 8294
Scoket 8343
WJGEAR 19 - 19
GEAR (Continued)

INSTALLATION
(1) Lubricate new o-ring and teflon rings with
power steering fluid and install on the rack piston/
valve assembly.
(2) Lubricate the rack piston/valve assembly with
power steering fluid.
(3) Slide the assembly into the gear housing.
(4) Install new stub shaft housing o-rings and
install the housing. Tighten the housing bolts to 62
N´m (46 ft. lbs.).
(5) Install new o-ring on the pitman shaft cover.
(6) Install the pitman shaft into the gear housing.
(7) Install the pitman shaft cover bolts and tighten
to 62 N´m (46 ft. lbs.).
(8) Perform over-center rotation torque adjustment
(Refer to 19 - STEERING/GEAR - ADJUSTMENTS)..
(9) Install the steering gear (Refer to 19 - STEER-
ING/GEAR - INSTALLATION).
(10) Fill the power steering pump (Refer to 19 -
STEERING/PUMP - STANDARD PROCEDURE).
STUB SHAFT HOUSING
REMOVAL
NOTE: If stub shaft housing, seal or bearing is dam-
aged the housing must be replaced.
(1) Remove the steering gear (Refer to 19 -
STEERING/GEAR - REMOVAL).
(2) Remove stub shaft housing bolts (Fig. 19).
(3) Remove housing from the steering gear (Fig.
20).
(4) Remove stub shaft housing o-rings (Fig. 15).
INSTALLATION
NOTE: If stub shaft housing, seal or bearing is dam-
aged the housing must be replaced.
(1) Grease stub shaft seal withspecial grease-
supplied with new stub shaft housing.
(2) Install new stub shaft housing o-rings.
(3) Install housing on the steering gear.
(4) Install the housing bolts and tighten to 62 N´m
( 46 ft. lbs.).
(5) Install the steering gear (Refer to 19 - STEER-
ING/GEAR - INSTALLATION).
(6) Fill the power steering pump (Refer to 19 -
STEERING/PUMP - STANDARD PROCEDURE).
Fig. 19 Stub Shaft Housing
1 - STUB SHAFT HOUSING
2 - BOLTS
3 - STUB SHAFT
Fig. 20 Housing Removal
1 - STEERING GEAR
2 - HOUSING
WJGEAR 19 - 25
RACK PISTON/VALVE ASSEMBLY (Continued)

PUMP
TABLE OF CONTENTS
page page
PUMP
DESCRIPTION - 4.0L, 4.7L................32
OPERATION
OPERATION - 4.7L....................32
OPERATION - 4.0L....................32
DIAGNOSIS AND TESTING - PUMP LEAKAGE . 33
STANDARD PROCEDURE
STANDARD PROCEDURE - INITIAL
OPERATION - 4.0L....................33
STANDARD PROCEDURE - INITIAL
OPERATION - 4.7L....................33
REMOVAL
REMOVAL - 4.0L ENGINE...............34
REMOVAL - 4.7L ENGINE...............34
INSTALLATION
INSTALLATION - 4.0L ENGINE...........34
INSTALLATION - 4.7L ENGINE...........34
SPECIFICATIONS
TORQUE CHART......................35
SPECIAL TOOLS
POWER STEERING PUMP..............36
FLUID COOLER
DESCRIPTION.........................36
REMOVAL.............................36
INSTALLATION.........................37
HOSES - 4.0L
DESCRIPTION
DESCRIPTION - PRESSURE LINE........37
DESCRIPTION - RETURN LINE...........37
OPERATION
OPERATION - PRESSURE LINE..........37
OPERATION - RETURN LINE............37
REMOVAL.............................37
INSTALLATION.........................37
HOSES - 4.7L
DESCRIPTION
DESCRIPTION - 1/2º PRESSURE HOSE....38DESCRIPTION - 1/2º RETURN HOSE......38
DESCRIPTION - 3/8º PRESSURE HOSE....38
DESCRIPTION - 3/8º GEAR OUTLET HOSE . 38
DESCRIPTION - 3/8º RETURN HOSE......38
OPERATION
OPERATION - 1/2º PRESSURE HOSE......38
OPERATION - 1/2º RETURN HOSE........38
OPERATION - 3/8º PRESSURE HOSE......39
OPERATION - 3/8º GEAR OUTLET HOSE . . . 39
OPERATION - 3/8ºRETURN HOSE........39
REMOVAL
REMOVAL - 1/29PRESSURE HOSE.......39
REMOVAL - 1/29RETURN HOSE..........39
REMOVAL - 3/89PRESSURE HOSE.......39
REMOVAL - 3/89RETURN HOSE..........39
REMOVAL - 3/89GEAR OUTLET HOSE.....40
REMOVAL - INLET COOLER HOSE........40
REMOVAL - OUTLET COOLER HOSE......40
INSTALLATION
INSTALLATION - 1/29PRESSURE HOSE....40
INSTALLATION - 1/29RETURN HOSE......40
INSTALLATION - 3/89PRESSURE HOSE....41
INSTALLATION - 3/89RETURN HOSE......41
INSTALLATION - 3/89GEAR OUTLET HOSE . 41
INSTALLATION - INLET COOLER HOSE....41
INSTALLATION - OUTLET COOLER HOSE . . 41
PULLEY
DESCRIPTION
POWER STEERING PUMP PULLEY - 3.1L
DIESEL.............................41
REMOVAL.............................41
INSTALLATION.........................42
RESERVOIR
REMOVAL.............................42
INSTALLATION.........................42
WJPUMP 19 - 31

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)