2009 INFINITI QX56 suspension

RSU-20
< REMOVAL AND INSTALLATION >
FRONT LOWER LINK
 Check ball joint. Replace suspension arm assembly if any of thefollowing exists:
- Ball stud is worn.
- Joint is hard to swing.
- Play in axial direction is excessive.
INSTALLATION
Installation is in the reverse order of removal.
 Tighten the nuts and bolts to specification. Refer to RSU-19, "Removal and Installation"
.
 Perform final tightening of nuts and bolts for the links (rubber bushing) under unladen condition (unladen condition means that the fuel tank, engine coolant and l ubricants are at the full specification, and the spare
tire, jack, hand tools, and mats are in their designated positions) with the tires on level ground.
 Check the wheel alignment. Refer to RSU-6, "Wheel AlignmentInspection"
.
Swinging force “A” : Refer to
RSU-29, "Ball Joint"

Turning force “B” : Refer to RSU-29, "Ball Joint"

Vertical end play “C” : Refer to RSU-29, "Ball Joint"

SFA858A
Revision: December 20092009 QX56

REAR LOWER LINK & COIL SPRINGRSU-21
< REMOVAL AND INSTALLATION >
C
DF
G H
I
J
K L
M A
B
RSU
N
O P
REAR LOWER LINK & COIL SPRING
Removal and InstallationINFOID:0000000005889876
REMOVAL
1. Remove the wheel and tire assembly using power tool. Refer to WT-41, "Adjustment".
2. If equipped with rear load leveling air suspension system, use CONSULT-III “EXHAUST SOLENOID”
active test to release the air pressure from the rear load leveling air suspension system.
3. If equipped with the rear load leveling air suspension system, for removing the LH rear lower link and coil spring, remove the
height sensor arm bracket bolt from the rear lower link.
4. Remove speed sensor harness and brackets from rear lower link.
5. Set a suitable jack to relieve the coil spring tension and support the rear lower link.
6. Loosen the rear lower link adjusting bolt and nut connected to the rear suspension member, using power tool.
7. Remove the rear lower link bolt and nut from the knuckle using power tool.
LEIA0080E
LEIA0077E
LEIA0009E
LEIA0077E
Revision: December 20092009 QX56

RSU-22
< REMOVAL AND INSTALLATION >
REAR LOWER LINK & COIL SPRING
8. 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.
9. Remove the rear lower link adjusting bolt and nut from the rear suspension member using power tool, then remove the rear
lower link.
INSPECTION AFTER REMOVAL
Check the coil spring and rubber seats for deformation, cracks, or other damage and replace if necessary.
INSTALLATION
Installation is in the reverse order of removal.
 Tighten the nuts and bolts to specification. Refer to RSU-21, "Removal and Installation"
.
 When installing the upper and lower rubber seats for the rear coil springs, the arrow embossed on the rubber seats must point out
toward the wheel and tire assembly.
 After installing the rear lower link and coil spring, check the wheel alignment and adjust if necessary. Refer to RSU-6, "Wheel Align-
mentInspection".
LEIA0009E
LEIA0076E
Revision: December 20092009 QX56

RSU-24
< REMOVAL AND INSTALLATION >
REAR LOAD LEVELING AIR SUSPENSION COMPRESSOR ASSEMBLY
REAR LOAD LEVELING AIR SUSPENSION COMPRESSOR ASSEMBLY
Removal and InstallationINFOID:0000000003772299
Rear Load Leveling Air Suspension System
REMOVAL
1. Use CONSULT-III "EXHAUST SOLENOID" active test to release the air pressure from the rear load level-
ing air suspension system.
2. Disconnect the electrical connectors for the rear load leveling air suspension compressor assembly.
3. Unclip the rubber cover to access the rear load leveling air suspension compressor assembly.
4. Disconnect the rear load leveling air suspension hoses at the rear load leveling air suspension compressor assembly.
 To disconnect the hoses, push in on the lock ring using a suit-
able tool and pull the hose out.
AWEIA0054GB
1. Rear load leveling air suspension
hose, RH 2. Shock absorber, RH 3. Height sensor
4. Rear load leveling air suspension hose, LH 5. Shock absorber, LH 6. Rear load leveling air suspension
compressor assembly
Front
LEIA0074E
Revision: December 20092009 QX56

REAR LOAD LEVELING AIR SUSPENSION COMPRESSOR ASSEMBLY
RSU-25
< REMOVAL AND INSTALLATION >
C
D F
G H
I
J
K L
M A
B
RSU
N
O P
5. Remove the four bolts that mount the rear load leveling air sus- pension compressor assembly to the underbody.
INSTALLATION
Installation is in the reverse order of removal.
 To connect the rear load leveling air suspension hoses, the lockring must be fully seated in the fitt ing. Insert the hose (B) into the
lock ring (A) until the lock ring (A) is touching the hose (B) as
shown. Pull on the hose to check that it is securely inserted.
LEIA0090E
LEIA0078E
Revision: December 20092009 QX56

RSU-26
< REMOVAL AND INSTALLATION >
CONTROL UNIT
CONTROL UNIT
Removal and InstallationINFOID:0000000003772300
REMOVAL
1. Remove the rear LH interior trim panel. Refer to INT-14, "Removal and Installation" .
2. Disconnect the battery negative terminal.
3. Disconnect the suspension control unit electrical connector.
4. Remove the two bolts and remove the suspension control unit.
INSTALLATION
Installation is in the reverse order of removal.
Initialization ProcedureINFOID:0000000003772301
1. If control unit has been replaced, proceed to step 2. If control unit has not been replaced, use CONSULT-
III “CLEAR HEIGHT INI” work support function to clear initialization flag and value. The CK SUSP warning
lamp should illuminate. Using CONSULT-III “EXHAUST SOLENOID” active test, release the air pressure
from the rear load leveling air suspension system.
2. Roll vehicle forward and backward.
3. Use CONSULT-III “ADJUST HEIGHT INI” work support function to set initialization condition.
4. Confirm that CK SUSP warning lamp is OFF.
LEIA0100E
Suspension control unit bolts : 6 N·m (0.6 kg-m, 53 in-lb)
Revision: December 20092009 QX56

HEIGHT SENSORRSU-27
< REMOVAL AND INSTALLATION >
C
DF
G H
I
J
K L
M A
B
RSU
N
O P
HEIGHT SENSOR
Removal and InstallationINFOID:0000000003772302
Rear Load Leveling Air Suspension System
REMOVAL
1. Use CONSULT-III “EXHAUST SOLENOID ” active test to release the air pressure from the rear load level-
ing air suspension system.
2. Disconnect the electrical connector for the height sensor.
3. Remove the two height sensor bolts and height sensor arm bracket bolt.
4. Remove the height sensor.
INSTALLATION
Installation is in the reverse order of removal.
AWEIA0054GB
1. Rear load leveling air suspension hose, RH 2. Shock absorber, RH 3. Height sensor
4. Rear load leveling air suspension hose, LH 5. Shock absorber, LH 6. Rear load leveling air suspension
compressor assembly
Front
LEIA0080E
Revision: December 20092009 QX56

RSU-30
< SERVICE DATA AND SPECIFICATIONS (SDS)
SERVICE DATA AND SPECIFICATIONS (SDS)
Wheelarch Height (Unladen*
1)INFOID:0000000003772305
Unit: mm (in)
*1: Fuel, engine coolant and engine oil full. Spare tire, jack, hand tools and mats in designated positions.
*2: Verify the vehicle height. If vehicle height is not within ± 10 mm (0.39 in) of the specification, perform the control unit initialization pro-
cedure. Refer to RSU-26, "Initialization Procedure"
.
Suspension type
Air leveling*
2
Applied model2WD 4WD
Front wheelarch height (Hf) 920
(36.22) 937
(36.89)
Rear wheelarch height (Hr) 917
(36.10) 937
(36.89)
LEIA0085E
Revision: December 20092009 QX56