2005 INFINITI QX4 low oil pressure

STEERING WHEEL
PS-7
C
D
E
F
H
I
J
K
L
MA
B
PS
Revision: October 20052005 QX56
STEERING WHEELPFP:48430
On-Vehicle Inspection and ServiceEGS000UC
CHECKING CONDITION OF INSTALLATION

Check installation condition of steering gear assembly, front suspension, axle and steering column.

Check if movement exists when steering wheel is moved up and down, to the left and right and to the axial
direction.

Check if the mounting nuts for steering gear assembly are loose.
Refer to PS-15, "
POWER STEERING GEAR AND LINKAGE" .
CHECKING STEERING WHEEL PLAY
1. Turn tires straight ahead, start engine, then turn steering wheel to the left and right lightly, and measure
steering wheel movement on the outer circumference when steering wheel is turned up to the point where
tires start moving.
CHECKING NEUTRAL POSITION ON STEERING WHEEL

Check neutral position on steering wheel after confirming that front wheel alignment is correct. Refer to
FSU-6, "
Front Wheel Alignment" .
1. Turn tires straight ahead, check if steering wheel is in the neutral position.
2. If it is not in the neutral position, remove steering wheel and reinstall it correctly.
3. If the neutral position cannot be attained by repositioning the steering wheel two teeth or less on steering
stem, loosen tie-rod lock nuts of steering outer sockets, then adjust tie-rods by the same amount in the
opposite direction.
CHECKING STEERING WHEEL TURNING FORCE
1. Park vehicle on a level, dry surface and set parking brake.
2. Start engine.
3. Bring power steering fluid up to operating temperature of 60° – 80°C (140° – 176°F).
4. Tires need to be inflated to specified pressure. Refer to WT-34, "
Tire" .
5. Check steering wheel turning force using Tool when steering
wheel has been turned 360° from the neutral position.
6. If steering wheel turning force is out of specification, inspect the
following:

Steering column. Refer to PS-11, "INSPECTION AFTER
REMOVAL" .

Power steering oil pump. Refer to PS-26, "CHECKING
RELIEF OIL PRESSURE" .
7. If steering column and power steering oil pump meet specifications, replace steering gear. Refer to PS-15,
"Removal and Installation" . End play of the axial direction for steering wheel : 0 mm (0 in)
LGIA0024E
Steering wheel play on the outer circumference : 0 − 35 mm (0 − 1.38 in)
Tool number : J-44372
Steering wheel
turning force: 39 N (4 kg-f, 9 lb-f) or less
WGIA0035E

PS-16
POWER STEERING GEAR AND LINKAGE
Revision: October 20052005 QX56
8. Remove oil piping (high pressure side and low pressure side)
from steering gear assembly, then drain fluid from piping.
9. Remove lower joint mounting bolt of lower shaft.
10. Remove mounting bolts and nuts of steering gear assembly
using power tool, and then remove steering gear assembly from
vehicle.
INSTALLATION
Installation is in the reverse order of removal.

After removing/installing or replacing steering components, check wheel alignment. Refer to FSU-6,
"Front Wheel Alignment" .

After adjusting wheel alignment, adjust neutral position of steering angle sensor. Refer to BRC-62,
"Adjustment of Steering Angle Sensor Neutral Position" .

With steering wheel in straight ahead position, make sure slit of
lower joint fits with the projection on rear cover cap, while check-
ing that mark on steering gear assembly aligns with mark on
rear cover cap

After installation, bleed the air from the steering hydraulic system. Refer to PS-6, "Air Bleeding Hydraulic
System" .
LGIA0032E
LGIA0029E
LGIA0024E
SST 4 91 C

PS-26
POWER STEERING OIL PUMP
Revision: October 20052005 QX56
POWER STEERING OIL PUMPPFP:49110
On-Vehicle Inspection and ServiceEGS000UJ
CHECKING RELIEF OIL PRESSURE
CAUTION:
Before starting work, confirm belt tension is proper.
1. Connect Tool between oil pump discharge connector and high
pressure hose and then bleed air from the hydraulic circuit.
2. Start engine. Allow engine to run until tank temperature reaches 50 – 80°C (122 – 176°F).
CAUTION:

Warm up engine with shut-off valve fully opened. If engine is started with shut-off valve closed,
fluid pressure in power steering pump increases to maximum. This will raise fluid temperature
excessively.

Be careful not to contact hose with belt when engine is started.
3. With engine at idle, close shut-off valve and read the relief oil pressure.
CAUTION:
Do not close shut-off valve of pressure gauge for more than 10 seconds.
4. After measurement, open shut-off valve slowly.

If relief oil pressure is outside the specification, disassemble and repair oil pump. Refer to PS-17, "Dis-
assembly and Assembly" .
5. After inspection, disconnect oil pressure gauge and oil pressure gauge adapter from hydraulic circuit, con-
nect oil pump discharge connector and high pressure hose. Add fluid and bleed air from hydraulic circuit
thoroughly. Refer to PS-6, "
Air Bleeding Hydraulic System" .
Removal and InstallationEGS000UK
REMOVAL
1. Drain power steering fluid from reservoir tank.
2. Remove engine room cover. Refer to EM-11, "
Removal and Installation" .
3. Remove air duct assembly. Refer to EM-14, "
Removal and Installation" .
4. Remove power steering reservoir tank.
5. Remove serpentine drive belt belt from auto tensioner and power steering pump. Refer to EM-12,
"Removal and Installation" .
6. Disconnect pressure sensor electrical connector.
7. Remove high pressure and low pressure piping from power steering oil pump. Refer to PS-31, "
HYDRAU-
LIC LINE" .
8. Remove mounting bolts, then remove power steering pump.
INSTALLATION
Installation is in the reverse order of removal. Refer to PS-31, "HYDRAULIC LINE" for tightening torque.

After installation, bleed air. Refer to PS-6, "Air Bleeding Hydraulic System" .
NOTE:
Belt tension is automatic and requires no adjustment.
Tool number:
Pressure gauge and shut-off valveKV48103500
(J26357 and J26357-10)
Oil pump sideConnector A and
O-ringKV48105300-4 and 5295262U10
(—)
Eye-bolt and O-ringKV48105300-3 and 5295262U00
(—)
High pressure
piping sideConnector B and
O-ringKV48105300-1 and 5295262U00
(—)
NutKV48105300-2
( — )
Relief oil pressure
: 9.0 – 9.8 mPa (91.77 – 99.93 kg/cm2 , 1305.34 – 1421.37 psi)
SGIA0570E

POWER STEERING OIL PUMP
PS-27
C
D
E
F
H
I
J
K
L
MA
B
PS
Revision: October 20052005 QX56
Disassembly and AssemblyEGS000UL
INSPECTION BEFORE DISASSEMBLY
Disassemble power steering oil pump only if the following conditions are found.

Oil leakage from oil pump

Deformed or damaged pulley

Poor performance
DISASSEMBLY
CAUTION:
When retaining drive shaft in a vise, always use copper or aluminum plates between vise and shaft.
NOTE:
Mount the oil pump in a vise as needed.
1. Unscrew three bracket bolts and remove bracket from rear cover.
2. Unscrew four rear cover bolts and remove rear cover from body assembly.
3. Remove gasket from body assembly.
4. Remove lock pin, cartridge and side plate from body assembly.
5. Remove pulley from drive shaft assembly.
1. Bracket 2. Rear cover 3. Gasket
4. Lock pin 5. Cam ring 6. Rotor
7. Vane 8. Cartridge 9. Side plate
10. O-ring 11. Body assembly 12. Oil seal
13. Drive shaft assembly 14. Snap ring 15. Pulley
16. Spring washer 17. Flow control valve 18. Pressure sensor
19. Connector bolt 20. Copper washer 21. Bracket
22. Suction pipe 23. O-ring
WGIA0076E

HYDRAULIC LINE
PS-31
C
D
E
F
H
I
J
K
L
MA
B
PS
Revision: October 20052005 QX56
HYDRAULIC LINEPFP:49721
Removal and InstallationEG S00 0UM
Refer to the following illustration for hydralic line removal.
1. Reservoir tank 2. Suction hose 3. High pressure hose
4. Oil cooler 5. Steering gear assembly 6. Reservoir tank bracket
7. Eye bolt
WGIA0096E

SERVICE DATA AND SPECIFICATIONS (SDS)
PS-35
C
D
E
F
H
I
J
K
L
MA
B
PS
Revision: October 20052005 QX56
Steering GearEGS0014O
Oil PumpEGS000UR
Steering FluidEGS000US
Steering gear modelPR26AM
Rack neutral position, dimension “L” (rack stroke) 85.5 mm (3.36 in)
Rack sliding forceAt the neutral point:
Range within ± 11.5 mm
(±0.453 in) from the neutral
position
(in power ON)Area average value 250.1 − 308.9 N (25.5 − 31.5 kg, 56.2 − 69.5 lb)
Area minimum value 200 N (20.4 kg, 45 lb)
Allowable variation 98 N (10 kg, 22 lb) or less
STC0034D
Relief oil pressure
9.0 − 9.8 mPa (91.77 − 99.93 kg/cm2 , 1305.34 − 1421.37 psi)
Fluid capacity
Approx. 1.0 (1-1/8 US qt, 7/8 Imp qt)

REAR SUSPENSION MEMBER
RSU-31
C
D
F
G
H
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K
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MA
B
RSU
Revision: October 20052005 QX56
Rear Load Leveling Air Suspension System
REMOVAL
1. Use the CONSULT-II “EXHAUST SOLENOID” active test to release the air pressure from the rear load
leveling air suspension system.
2. Disconnect the electrical connectors for the height sensor and the rear load leveling air suspension com-
pressor assembly.
3. Unclip the rubber cover to access the rear load leveling air suspension compressor assembly.
1. Seat belt latch anchor 2. Stabilizer bar bushing 3. Stabilizer bar clamp
4. Stabilizer bar 5. Connecting rod 6. Front lower link
7. Knuckle 8. Bushing 9. Rear lower link
10. Shock absorber 11. Suspension arm 12. Lower rubber seat
13. Coil spring 14. Upper rubber seat 15. Rear suspension member
16. Spare tire bracket 17. Bound bumper
LEIA0072E
1. Rear load leveling air suspension
hose, RH2. Shock absorber, RH 3. Height sensor
4. Rear load leveling air suspension
hose, LH5. Shock absorber, LH 6. Rear load leveling air suspension
compressor assembly (includes the
bracket and rubber cover)

REAR LOWER LINK & COIL SPRING
RSU-39
C
D
F
G
H
I
J
K
L
MA
B
RSU
Revision: October 20052005 QX56
REAR LOWER LINK & COIL SPRINGPFP:551B0
Removal and Installation EES001HM
REMOVAL
1. Remove the wheel and tire assembly using power tool. Refer to WT-7, "Rotation" .
2. Use CONSULT-II "EXHAUST SOLENOID" active test to release the air pressure from the rear load level-
ing air suspension system.
3. For removing the LH rear lower link and coil spring, remove the
height sensor arm bracket bolt from the LH rear lower link.
4. Set a suitable jack to relieve the coil spring tension from the rear
lower link.
WAR NIN G:
Do not compress the coil spring when setting the jack.
5. Loosen the rear lower link adjusting bolt and nut connected to
the rear suspension member, using power tool.
6. Remove the rear lower link bolt and nut from the knuckle using
power tool.
7. Slowly lower the suitable jack to release the coil spring tension. Then remove the upper rubber seat, coil
spring, and lower rubber seat from the rear lower link.
LEIA0080E
LEIA0077E
LEIA0009E
LEIA0077E