DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - POWER STEERING SYSTEM
STEERING NOISE
There is some noise in all power steering systems. One of the most common is a hissing sound evident at a
standstill parking. Or when the steering wheel is at the end of it's travel. Hiss is a high frequency noise similar
to that of a water tap being closed slowly. The noise is present in all valves that have a high velocity fluid passing
through an orifice. There is no relationship between this noise and steering performance.
CONDITION POSSIBLE CAUSES CORRECTION
OBJECTIONAL HISS OR
WHISTLE1. Steering intermediate shaft to dash panel
seal.1. Check and repair seal at dash
panel.
2. Noisy valve in power steering gear. 2. Replace steering gear.
RATTLE OR CLUNK 1. Gear mounting bolts loose. 1. Tighten bolts to specification.
2. Loose or damaged suspension
components/track bar.2. Inspect and repair suspension.
3. Loose or damaged steering linkage. 3. Inspect and repair steering
linkage.
4. Internal gear noise. 4. Replace gear.
5. Pressure hose in contact with other
components.5. Reposition hose.
CHIRP OR SQUEAL 1. Loose belt. 1. Adjust or replace.
2. Belt routing. 2. Verify belt routing is correct.
WHINE OR GROWL 1. Low fluid level. 1. Fill to proper level.
2. Pressure hose in contact with other
components.2. Reposition hose.
3. Internal pump noise. 3. Replace pump.
4. Air in the system. 4. Perform pump initial operation.
SUCKING AIR SOUND 1. Loose return line clamp. 1. Replace clamp.
2. O-ring missing or damaged on hose
fitting.2. Replace o-ring.
3. Low fluid level. 3. Fill to proper level.
4. Air leak between pump and reservoir. 4. Repair as necessary.
SCRUBBING OR
KNOCKING1. Wrong tire size. 1. Verify tire size.
2. Wrong gear. 2. Verify gear.
19 - 2 STEERINGWJ
STEERING (Continued)
BINDING AND STICKING
CONDITION POSSIBLE CAUSE CORRECTION
DIFFICULT TO TURN WHEEL
STICKS OR BINDS1. Low fluid level. 1. Fill to proper level.
2. Tire pressure. 2. Adjust tire pressure.
3. Steering component. 3. Inspect and lube.
4. Loose belt. 4. Adjust or replace.
5. Low pump pressure. 5. Pressure test and replace if
necessary.
6. Column shaft coupler binding. 6. Replace coupler.
7. Steering gear worn or out of
adjustment.7. Repair or replace gear.
8. Ball joints binding. 8. Inspect and repair as necessary.
9. Belt routing. 9. Verify belt routing is correct.
4.7L Hydraulic fan motor steering output
lowPressure / Flow test fans steering
output flow
INSUFFICIENT ASST. OR POOR RETURN TO CENTER
CONDITION POSSIBLE CAUSE CORRECTION
HARD TURNING OR MOMENTARY
INCREASE IN TURNING EFFORT1. Tire pressure. 1. Adjust tire pressure.
2. Low fluid level. 2. Fill to proper level.
3. Loose belt. 3. Adjust or replace.
4. Lack of lubrication. 4. Inspect and lubricate steering and
suspension compnents.
5. Low pump pressure or flow. 5. Pressure and flow test and repair
as necessary.
6. Internal gear leak. 6. Pressure and flow test, and repair
as necessary.
7. Belt routing. 7. Verify belt routing is correct.
4.7L8. Low flow / pressure from fan
motor8. Pressure and flow test and repair
as necessary.
STEERING WHEEL
DOES NOT WANT TO RETURN TO
CENTER POSITION1. Tire pressure. 1. Adjust tire pressure.
2. Wheel alignment. 2. Align front end.
3. Lack of lubrication. 3. Inspect and lubricate steering and
suspension compnents.
4. High friction in steering gear. 4. Test and adjust as necessary.
5. Ball joints binding. 5. Inspect and repair as necessary.
NOTE:
Some roads will cause a vehicle to drift, due to the crown in the road.
WJSTEERING 19 - 3
STEERING (Continued)
LOOSE STEERING AND VEHICLE LEADS/DRIFTS
CONDITION POSSIBLE CAUSE CORRECTION
EXCESSIVE PLAY IN STEERING
WHEEL1. Worn or loose suspension or
steering components.1. Repair as necessary.
2. Worn or loose wheel bearings. 2. Repair as necessary.
3. Steering gear mounting. 3. Tighten gear mounting bolts to
specification.
4. Gear out of adjustment. 4. Adjust gear to specification.
5. Worn or loose steering coupler. 5. Repair as necessary.
VEHICLE PULLS TO ONE SIDE
DURING BRAKING1. Tire Pressure. 1. Adjust tire pressure.
2. Air in brake hydrauliics system. 2. Bleed brake system.
3. Worn brake components. 3. Repair as necessary.
VEHICLE LEADS OR DRIFTS
FROM STRAIGHT AHEAD
DIRECTION ON UNCROWNED
ROAD.1. Tire pressure. 1. Adjust tire pressure.
2. Radial tire lead. 2. Cross front tires.
3. Brakes dragging. 3. Repair as necessary.
4. Wheel alignment. 4. Align vehicle.
5. Weak or broken spring. 5. Replace spring.
6. Loose or worn steering/
suspension components.6. Repair as necessary.
7. Cross caster out of spec. 7. Adjust or replace axle as
necessary.
DIAGNOSIS AND TESTING - STEERING FLOW
AND PRESSURE
The following procedure is used to test the opera-
tion of the power steering system on the vehicle. This
test will provide the gallons per minute (GPM) or
flow rate of the power steering pump along with the
maximum relief pressure. Perform test any time a
power steering system problem is present. This test
will determine if the power steering pump or power
steering gear is not functioning properly. The follow-
ing pressure and flow test is performed using Power
Steering Analyzer Tool kit 6815 (Fig. 2) and Adapter
Kit 6893.
FLOW AND PRESSURE TEST
(1) Check the power steering belt to ensure it is in
good condition and adjusted properly.
(2) Connect pressure gauge hose from the Power
Steering Analyzer to Tube 6865.
(3) Connect Adapter 6826 to Power Steering Ana-
lyzer test valve end.
(4) Disconnect the high pressure hose from the
power steering pump.
(5) Connect Tube 6865 to the pump hose fitting.(6) Connect the power steering hose from the
steering gear to Adapter 6826.
(7) Open the test valve completely.Fig. 2 Power Steering Analyzer
1 - TUBE
2 - ADAPTER FITTINGS
3 - ANALYZER
4 - GAUGE HOSE
19 - 4 STEERINGWJ
STEERING (Continued)
(8) Start engine and let idle long enough to circu-
late power steering fluid through flow/pressure test
gauge.
(9) Shut off the engine and check the fluid level,
add fluid as necessary. Start engine again and let
idle.
(10) The initial pressure reading should be
345-552 kPa (50-80 psi). If pressure is higher inspect
the hoses for restrictions and repair as necessary.
(11) Increase the engine speed to 1500 RPM and
read the flow meter. The reading should be 2.4 - 2.8
GPM, if the reading is below this specification the
pump should be replaced.
CAUTION: This next step involves testing maximum
pump pressure output and flow control valve oper-
ation. Do not leave valve closed for more than three
seconds as the pump could be damaged.
(12) Close valve fully three times for three seconds
and record highest pressure indicated each time.All
three readings must be at pump relief pressure
specifications and within 345 kPa (50 psi) of
each other.
²Pressures above specifications but not within
345 kPa (50 psi) of each other, replace pump.
²Pressures within 345 kPa (50 psi) of each other
but below specifications, replace pump.
CAUTION: Do not force the pump to operate against
the stops for more than 2 to 4 seconds at a time
because, pump damage will result.
(13) Open the test valve and turn the steering
wheel to the extreme left and right positions against
the stops. Record the highest pressure reading at
each position. Compare readings to the pump specifi-
cations chart. If pressures readings are not within 50
psi. of each other, the gear is leaking internally and
must be repaired.
GEAR INLET SPECIFICATIONS 4.0L & 4.7L
ENGINERELIEF
PRESSURE 50FLOW RATE
(GPM)
4.0L 9653 kPa (1400 psi)
1500 RPM 2.4 - 2.8
GPM
4.7L 9653 kPa (1450 psi)
PUMP MOTOR SPECIFICATIONS 4.7L
ENGINERELIEF
PRESSURE 50FLOW RATE
(GPM)
4.7L 9653 kPa (1900 psi)1100 RPM 2.4-2.8
GPM Minium
@ 200 psi
DIAGNOSIS AND TESTING - 4.7L -
HYDRAULIC
The following procedures are used to test the oper-
ation of the power steering and hydraulic fan sys-
tems on the vehicle. This test will provide the gallons
per minute (GPM) or flow rate of the power steering
pump along with any maximum relief pressure. Per-
form test anytime a power steering system problem
is present. This test will determine if the power
steering pump, hydraulic fan, and power steering
gear are not functioning properly. It will also deter-
mine if the flow coming out of the hydraulic fan
motor is sufficient for the power steering gear. The
following pressure and flow test is performed using
the Power Steering Analyzer Tool kit 6815 (Fig. 2)
and Adapter kit 8630 (Fig. 3).
FLOW TEST - FLOW FROM POWER STEERING
PUMP
(1) Check the power steering belt to ensure it is in
good condition and adjusted properly.
(2) Connect the pressure gauge hose from the
Power Steering Analyzer to Tube 8630-2.
(3) Connect Adapter 8630-3 to Power Steering
Analyzer test valve end.
(4) Disconnect the high pressure hose from the
power steering pump.
(5) Connect Tube 8630-2 to the pump hose fitting.
(6) Connect the power steering hose from the fan
motor to Adapter 8630-3.
(7) Open the test valve completely.
(8) Start engine and let idle long enough to circu-
late power steering fluid through the flow/pressure
test gauge.
(9) Shut off the engine and check the fluid level,
add fluid ass necessary. Start engine again and let
idle.
(10) The initial pressure reading should be 483 -
690 kPa (70 - 100 psi). If pressure is higher inspect
the hoses for restrictions and repair as necessary.
Fig. 3 4.7L HYDRAULIC POWER STEERING TEST
ADAPTERS
WJSTEERING 19 - 5
STEERING (Continued)
(11) Increase the engine speed to 1100 rpm and
read the flow meter. The reading should be 2.6 GPM
minimum, if the reading is below this specification,
the pump should be replaced.
FLOW AND PRESSURE TEST - FLOW FROM
HYDRAULIC FAN MOTOR TO STEERING GEAR
(should be done if necessary after the Pump flow
test)
(1) Connect the pressure gauge hose from the
Power Steering Analyzer to Fitting 8630-1.
(2) Connect Adapter 8630-4 to Power Steering
Analyzer test valve end.
(3) Disconnect the high pressure hose from the
power steering gear.
(4) Connect Fitting 8630-1 to the high pressure
hose.
(5) Connect Adapter 8630-4 to the power steering
gear.
(6) Open the test valve completely.
(7) Start engine and let idle long enough to circu-
late power steering fluid through the flow/pressure
test gauge.
(8) Shut off the engine and check the fluid level,
add fluid ass necessary. Start engine again and let
idle.
(9) The initial pressure reading should be 345-552
kPa (50-80 psi). If pressure is higher inspect the
hoses for restrictions and repair as necessary.(10) Increase the engine speed to 1500 RPM and
read the flow meter. The reading should be 2.4 - 2.8
GPM if the reading is below this specification the fan
should be replaced.
CAUTION: This next step involves testing maximum
fan motor steering relief pressure. Do not leave the
valve closed for more than three seconds.
(11) Close the valve fully three times for three sec-
onds and record highest pressures indicated each
time. All three readings must be at fan motor steer-
ing relief pressures.
(12) Open the test valve and turn the steering
wheel to the extreme left and right positions against
the stops. Record the highest pressure readings at
each position. If pressure readings are not within 50
psi from each other, the gear is leaking internally
and must be repaired.
PUMP MOTOR SPECIFICATIONS 4.7L
ENGINERELIEF
PRESSURE 50FLOW RATE
(GPM)
4.7L 9653 kPa (1900 psi)1100 RPM 2.4-2.8
GPM Minium
@ 200 psi
19 - 6 STEERINGWJ
STEERING (Continued)
(13) Remove the column coupler bolt (Fig. 13) and
slide the coupler off the column shaft.
(14) Remove the column mounting nuts (Fig. 13)
and lower column off mounting studs. Remove the
column from the vehicle.
(15) Remove the ignition switch, cylinder and
SKIM, (Refer to 19 - STEERING/COLUMN/LOCK
CYLINDER HOUSING - REMOVAL). (Fig. 14).INSTALLATION
WARNING: BEFORE SERVICING THE STEERING COL-
UMN THE AIRBAG SYSTEM MUST BE DISARMED.
FAILURE TO DO SO MAY RESULT IN ACCIDENTAL
DEPLOYMENT OF THE AIRBAG AND POSSIBLE PER-
SONAL INJURY. (Refer to 8 - ELECTRICAL/RE-
STRAINTS/DRIVER AIRBAG - INSTALLATION).
(1) Install the ignition switch, cylinder and SKIM-
,(Refer to 19 - STEERING/COLUMN/IGNITION
SWITCH - INSTALLATION).
(2) Install the column into the vehicle and lift the
column up onto the mounting studs. Install the
mounting nuts and tighten to 12 N´m (105 in. lbs.).
(3) Slid the coupler onto the column shaft and
install the coupler bolt. Tighten the coupler bolt to 49
N´m (36 ft. lbs.).
(4) Turn the ignition key to the on position then
release and install the shifter interlock cable (Fig.
12) into ignition lock cylinder housing.
(5) Verify ignition switch and shifter interlock
operation.,(Refer to 21 - TRANSMISSION/TRANS-
AXLE/AUTOMATIC - 42RE/GEAR SHIFT CABLE -
ADJUSTMENTS).
(6) Slide the multifuction switch and clock spring
onto the column as an assembly (Fig. 11).
(7) Install the multifuction switch mounting screw
(Fig. 10).
(8) Connect the multifuction switch (Fig. 9) and
ignition switch harness.
(9) Install the upper fixed shroud and mounting
screws (Fig. 8).
(10) Install the lower steering column shroud to
the steering column. Install and tighten the mount-
ing screw.
(11) Install the upper column shroud. Align the
upper shroud to the lower shroud and snap the two
shroud halves together.
(12) Install the knee blocker cover (Fig. 5),(Refer
to 23 - BODY/INSTRUMENT PANEL - INSTALLA-
TION).
(13) Install the cluster bezel by inserting it into
the instrument panel (Fig. 4).
(14) Align the steering wheel with the column
index spline and install the wheel on the column
shaft. Pull the clockspring wire harness through the
steering wheel armature spokes.
(15) Install and tighten the steering wheel mount-
ing nut to 61 N´m (45 ft. lbs.).
(16) Connect the steering wheel wire harness con-
nector to the clock spring connector.
(17) Install the airbag,(Refer to 8 - ELECTRICAL/
RESTRAINTS/DRIVER AIRBAG - INSTALLATION).
(18) Connect the negative (ground) cable to the
battery.
Fig. 13 Column Coupler Bolt And Mounting Nuts
1 - COLUMN MOUNTING NUTS
2 - COUPLER BOLT
Fig. 14 Ignition Switch And SKIM
1 - SKIM
2 - IGNITION SWITCH
WJCOLUMN 19 - 11
COLUMN (Continued)
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)