brake INFINITI QX56 2006 Factory Service Manual

BR-14
BRAKE PIPING AND HOSE
Revision: November 20092006 QX56
Inspection After InstallationEFS004W8
CAUTION:
If a leak is detected at the connections, retighten it or, if necessary, replace the damaged part.
1. Check brake tubes and hose connections for fluid leaks, damage, twist, deformation, contact with other
parts, and loose connections. Replace any damage parts.
2. While depressing brake pedal under a force of 785 N (80 kg-f, 177 lb-f) with engine running for approxi- mately 5 seconds, check for fluid leakage from each part.

BRAKE MASTER CYLINDERBR-15
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Revision: November 2009 2006 QX56
BRAKE MASTER CYLINDERPFP:46010
On-board InspectionEFS004W9
LEAK INSPECTION

Check for leaks at brake master cylinder to brake booster attachment point, reservoir tank, and brake tube
connections.
Removal and InstallationEFS004WA
REMOVAL
CAUTION:

Be careful not to splash brake fluid on painted areas; it may cause paint damage. If brake fluid is
splashed on painted areas, wash it away with water immediately.

Before removing brake master cylinder, depress the brake pedal 5-6 times with the key OFF to
deplete vacuum in the booster.
1. Drain brake fluid. Refer to BR-10, "
Drain and Refill" .
2. Disconnect harness connectors for fluid level sensor and pressure sensors.
3. Using a flare nut wrench, disconnect brake tube from brake master cylinder.
4. Remove brake master cylinder mounting nuts, and master cylinder assembly.
1. Reservoir cap 2. Fluid level sensor3. Grommet
4. Master cylinder sub-assembly 5. Front pressure sensor 6. Rear pressure sensor
7. Seal 8. Reservoir tank
BFIA0002E

BR-16
BRAKE MASTER CYLINDER
Revision: November 20092006 QX56
INSTALLATION

Installation is in the reverse order of removal.

Refill brake fluid and bleed air. Refer to BR-11, "Bleeding Brake System" .
CAUTION:

Refill with new brake fluid. Refer to MA-11, "RECOMMENDED FLUIDS AND LUBRICANTS" .

Do not reuse drained brake fluid.

Adjust brake pedal. Refer to BR-7, "ADJUSTMENT" .
Disassembly and AssemblyEFS004WB
DISASSEMBLY
CAUTION:

Master cylinder cannot be disassembled.

Remove reservoir tank only when absolutely necessary.
Pull reservoir tank off master cylinder sub-assembly, then remove grommets from master cylinder sub-assem-
bly body.
ASSEMBLY
CAUTION:

Never use mineral oil such as kerosene, gasoline during the cleaning and assembly process.

Do not drop parts. If a part is dropped, do not use it.
1. Apply brake fluid or rubber grease to new grommets, then insert into master cylinder sub-assembly. Refer to GI-46, "
RECOMMENDED CHEMICAL PRODUCTS AND SEALANTS" .
CAUTION:
Do not reuse grommet.
2. Install reservoir tank onto master cylinder sub-assembly.

BRAKE BOOSTERBR-17
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Revision: November 2009 2006 QX56
BRAKE BOOSTERPFP:47200
On-Vehicle ServiceEFS004WC
OPERATING CHECK
With engine stopped, change the vacuum to the atmospheric pres-
sure by depressing brake pedal several times. Then with brake
pedal fully depressed, start engine and when the vacuum pressure
reaches the standard, make sure the clearance between brake pedal
and floor panel decreases.
CAUTION:
Depressing pedal interval is approximately 5 seconds.
AIRTIGHT CHECK

Run engine at idle for approximately 1 minute, and stop it after
applying vacuum to booster. Depress brake pedal normally to
change the vacuum to the atmospheric pressure. Make sure dis-
tance between brake pedal and floor panel gradually increases.

Depress brake pedal while engine is running and stop engine
with pedal depressed. The pedal stroke should not change after
holding pedal down for 30 seconds.
CAUTION:
Depressing pedal interval is approximately 5 seconds.
BRA0037D
SBR365AA

BR-18
BRAKE BOOSTER
Revision: November 20092006 QX56
Removal and InstallationEFS004WD
REMOVAL
CAUTION:

Be careful not to deform or bend brake piping while removing and installing brake booster.

Replace clevis pin if it is damaged.

Be careful not to damage brake booster stud bolt threads. If brake booster is tilted or inclined dur-
ing installation, dash panel may damage the threads.

Attach the check valve in the correct direction.
1. Remove engine room cover with power tool. Refer to EM-12, "
Removal and Installation" .
2. Remove engine air duct assembly. Refer to EM-15, "
Removal and Installation" .
3. Remove brake piping from brake master cylinder.
4. Remove brake master cylinder. Refer to BR-15, "
Removal and Installation" .
5. Remove vacuum hose from brake booster. Refer to BR-20, "
VACUUM LINES" .
6. Disconnect active boost and delta stroke sensor harness connectors from brake booster assembly.
7. Remove brake pedal attachment snap pin and clevis pin from inside the vehicle.
8. Remove nuts on brake booster and brake pedal assembly.
9. Remove brake booster assembly from dash panel.
INSTALLATION
1. Loosen lock nut to adjust input rod length so that the length B (in the figure) satisfies the specified value.
2. After adjusting “B”, temporarily tighten lock nut and install
booster assembly to the vehicle.

Install a gaskets and spacer block between booster assembly
and the dash panel.
3. Connect brake pedal with clevis of input rod.
4. Install pedal bracket mounting nuts and tighten them to the specified torque.
5. Install brake piping from brake master cylinder to ABS actuator. Refer to BR-12, "
Hydraulic Circuit" .
1. Reservoir tank 2. Brake master cylinder 3. Gasket
4. Brake pedal 5. Lock nut 6. Spacer block
7. Brake booster 8. Active booster 9. Delta stroke sensor
BFIA0003E
Length “B” : 151 mm (5.94 in)
WFIA0382E

BRAKE BOOSTERBR-19
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Revision: November 2009 2006 QX56
6. Connect active boost and delta stroke sensor harness connectors to brake booster assembly.
7. Connect vacuum hose to brake booster.
8. Install master cylinder to booster assembly. Refer to BR-18, "
Removal and Installation" .
9. Adjust the height and play of brake pedal.
10. Tighten lock nut of input rod to specification.
11. Install engine air duct assembly. Refer to EM-15, "
Removal and Installation" .
12. Install engine room cover with power tool. Refer to EM-12, "
Removal and Installation" .
13. Refill with new brake fluid and bleed air. Refer to BR-11, "
Bleeding Brake System" .

BR-20
VACUUM LINES
Revision: November 20092006 QX56
VACUUM LINESPFP:41920
Removal and InstallationEFS004WE
1. Disconnect vacuum hose from hose clip.
2. Release clamps and disconnect vacuum hose.
3. Remove check valve from brake booster.
4. Installation is in the reverse order of removal.
CAUTION:

Insert vacuum hose for at least 24 mm (0.94 in).

Do not use lubricating oil during assembly.
InspectionEFS004WF
VISUAL INSPECTION
Check for improper assembly, damage and deterioration.
CHECK VALVE INSPECTION
Airtightness Inspection
Use a suitable vacuum pump to check. Connect to brake booster
side of check valve.
1. Hose clip 2. Clamp 3. Vacuum hose
4. Check valve
LFIA0216E
SBR225B
Check
valve
specifi-
cation : Vacuum decrease should be within 1.3
kPa (10 mmHg, 0.39 inHg) for 15 seconds
under a vacuum of – 66.7 kPa (– 500 mmHg,
– 19.69 inHg)
LFIA0217E

FRONT DISC BRAKEBR-21
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Revision: November 2009 2006 QX56
FRONT DISC BRAKEPFP:41000
On-vehicle InspectionEFS004WG
PAD WEAR INSPECTION

Inspect the thickness of pad through cylinder body inspection
hole. Use a scale for inspection if necessary.
ComponentsEFS004WH
Standard thickness : Refer to BR-32, "Front
Disc Brake" .
Repair limit thickness : Refer to BR-32, "
Front
Disc Brake" .
BRA0010D
1. Upper sliding pin 2. Sliding pin boot3. Torque member bolt
4. Torque member 5. Piston seal6. Piston
7. Inner pad 8. Pad retainer9. Outer pad
10. Piston boot 11. Union bolt12. Copper washer
13. Sliding pin bolt 14. Bleed valve15. Cylinder body
16. Cap 17. Brake hose18. Lower sliding pin
19. Outer shim 20. Inner shimA. Wear indicator
⇐ Front B. Models built before 3/8/2006 C. Models built on or after 3/8/2006
LFIA0251E

BR-22
FRONT DISC BRAKE
Revision: November 20092006 QX56
WARNING:
Clean dust on cylinder body and brake pads with a vacuum dust collector to minimize the hazard of
airborne particles or other materials.
CAUTION:

While removing cylinder body never depress brake pedal because piston will pop out.

It is not necessary to remove bolts on torque member and brake hose except for disassembly or
replacement of cylinder body. In this case, hang cylinder body with a wire so as not to stretch
brake hose.

Do not damage piston boot.

Burnish brake contact surface after refinishing or replacing rotors, after replacing pads, or if a soft
pedal occurs at very low mileage. Refer to BR-25, "
BRAKE BURNISHING PROCEDURE" .
Removal and Installation of Brake PadEFS004WI
REMOVAL
1. Remove tires from vehicle using power tool.
2. Remove lower sliding pin bolt.
3. Suspend cylinder body with a wire and remove pads, shims and pad retainers from torque member.
INSTALLATION
1. Push pistons in so that pad is firmly installed and mount cylinder body to torque member.
CAUTION:
By pushing in piston, brake fluid returns to master cylinder reservoir tank. Watch the level of the
surface of reservoir tank.
NOTE:
Using a disc brake piston tool (commercial service tool), makes it easier to push in piston.
2. Attach pad retainers, pads and shims to torque member.

Apply Molykote M-77 grease to pad retainer where brake pad
contacts and between pad and shim.
CAUTION:

When attaching pad retainer, attach it firmly so that it is
seated fully in the torque member as shown.

Do not get grease on the brake rotor friction surface.
3. Install lower sliding pin bolt and tighten it to the specified torque. Refer to BR-21, "
Components" .
4. Check brake for drag.
5. Install tires to the vehicle. Refer to WT-7, "
Rotation" .
Removal and Installation of Brake Caliper and Disc RotorEFS004WJ
REMOVAL
1. Remove tires from vehicle using power tool.
2. Drain brake fluid as necessary. Refer to BR-10, "
Drain and Refill" .
NOTE:
Do not remove union bolt unless removing cylinder body from vehicle.
3. Remove torque member bolts.
NOTE:
Position cylinder body aside using suitable wire, as necessary.
NOTE:
When servicing cylinder body, remove sliding pin bolts and torque member from cylinder body.
4. Remove disc rotor.
INSTALLATION
CAUTION:

Refill with new brake fluid. Refer to MA-11, "RECOMMENDED FLUIDS AND LUBRICANTS" .
PFIA0273E

FRONT DISC BRAKEBR-23
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Revision: November 2009 2006 QX56

Do not reuse drained brake fluid.
1. Install disc rotor.
2. Install sliding pin bolts and torque member to caliper, if removed. Refer to BR-21, "
Components" .
3. Install caliper assembly to the vehicle, then tighten the torque member bolts to the specified torque. Refer to BR-21, "
Compo-
nents" .
CAUTION:

When attaching caliper assembly to the vehicle, wipe any
oil off knuckle spindle, washers and caliper assembly
attachment surfaces.

Do not reuse caliper torque member bolts.
4. Install brake hose to cylinder body, then tighten union bolt to specification, as necessary. Refer to BR-21, "
Components" .
CAUTION:

Do not reuse copper washer.

Install brake hose to caliper assembly together with
union bolt and washers.
5. Refill with new brake fluid and bleed air. Refer to BR-11, "
Bleeding Brake System" .
6. Install tires to the vehicle. Refer to WT-7, "
Rotation" .
Disassembly and Assembly of Brake CaliperEFS004WK
DISASSEMBLY
1. Remove sliding pin bolt, and then remove the pad, shim, shim cover, and pad retainer from the torque member.
2. Remove sliding pins and sliding pin boots from torque member.
3. Place a wooden block as shown, and blow air from union bolt mounting hole to remove pistons and piston boots.
CAUTION:
Do not get your fingers caught in piston.
LFIA0209E
LFIA0214E
MAA0272D