2004 INFINITI QX56 service

BR-1
BRAKE SYSTEM
F BRAKES
CONTENTS
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SECTION BR
A
B
BR
Revision: August 20072004 QX56 PRECAUTIONS .......................................................... 3
Precautions for Supplemental Restraint System
(SRS) “AIR BAG” and “SEAT BELT PRE-TEN-
SIONER” .................................................................. 3
Precautions for Brake System .................................. 3
PREPARATION ........................................................... 4
Special Service Tool ................................................. 4
Commercial Service Tools ........................................ 4
NOISE, VIBRATION, AND HARSHNESS (NVH)
TROUBLESHOOTING ................................................ 5
NVH Troubleshooting Chart ..................................... 5
BRAKE PEDAL .......................................................... 6
Inspection and Adjustment ....................................... 6
INSPECTION ........................................................ 6
ADJUSTMENT ...................................................... 7
Removal and Installation .......................................... 8
REMOVAL ............................................................. 8
INSPECTION AFTER REMOVAL ......................... 9
INSTALLATION ..................................................... 9
BRAKE FLUID .......................................................... 10
On-board Inspection ............................................... 10
LEVEL CHECK ................................................... 10
Drain and Refill ....................................................... 10
Bleeding Brake System ...........................................11
BRAKE PIPING AND HOSE .................................... 12
Hydraulic Circuit ..................................................... 12
Removal and Installation of Front Brake Hose ....... 12
REMOVAL ........................................................... 12
INSTALLATION ................................................... 13
Removal and Installation of Rear Brake Hose ....... 13
REMOVAL ........................................................... 13
INSTALLATION ................................................... 13
Inspection After Installation .................................... 14
BRAKE MASTER CYLINDER .................................. 15
On-board Inspection ............................................... 15
LEAK INSPECTION ............................................ 15
Removal and Installation ........................................ 15
REMOVAL ........................................................... 15INSTALLATION ................................................... 16
Disassembly and Assembly .................................... 16
DISASSEMBLY ................................................... 16
ASSEMBLY ......................................................... 16
BRAKE BOOSTER ................................................... 17
On-Vehicle Service ................................................. 17
OPERATING CHECK .......................................... 17
AIRTIGHT CHECK .............................................. 17
Removal and Installation ........................................ 18
REMOVAL ........................................................... 18
INSPECTION AFTER REMOVAL ....................... 18
INSTALLATION ................................................... 19
VACUUM LINES ....................................................... 20
Removal and Installation ........................................ 20
Inspection ............................................................... 20
VISUAL INSPECTION ......................................... 20
CHECK VALVE INSPECTION ............................. 20
FRONT DISC BRAKE ............................................... 21
On-vehicle Inspection ............................................. 21
PAD WEAR INSPECTION ................................... 21
Components ........................................................... 21
Removal and Installation of Brake Pad .................. 22
REMOVAL ........................................................... 22
INSTALLATION ................................................... 22
Removal and Installation of Brake Caliper and Disc
Rotor ....................................................................... 22
REMOVAL ........................................................... 22
INSTALLATION ................................................... 23
Disassembly and Assembly of Brake Caliper
Assembly ................................................................ 23
DISASSEMBLY ................................................... 23
CALIPER INSPECTION ...................................... 24
ASSEMBLY ......................................................... 24
DISC ROTOR INSPECTION ............................... 25
BRAKE BURNISHING PROCEDURE ................. 25
REAR DISC BRAKE ................................................. 27
On-vehicle Inspection ............................................. 27
PAD WEAR INSPECTION ................................... 27
Components ........................................................... 27
Removal and Installation of Brake Pad .................. 28

BR-2Revision: August 20072004 QX56 REMOVAL ........................................................... 28
INSTALLATION .................................................... 28
Removal and Installation of Brake Caliper Assembly
and Disc Rotor ........................................................ 28
REMOVAL ........................................................... 28
INSTALLATION .................................................... 28
Disassembly and Assembly of Brake Caliper
Assembly ................................................................ 29
DISASSEMBLY ................................................... 29
CALIPER INSPECTION ...................................... 29
ASSEMBLY ......................................................... 30
DISC ROTOR INSPECTION ............................... 30
BRAKE BURNISHING PROCEDURE ................. 31SERVICE DATA AND SPECIFICATIONS (SDS) ......32
General Specifications ............................................32
Brake Pedal ............................................................32
Brake Booster .........................................................32
Check Valve ............................................................32
Front Disc Brake .....................................................32
Rear Disc Brake ......................................................33

PRECAUTIONS
BR-3
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MA
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BR
Revision: August 20072004 QX56
PRECAUTIONSPFP:00001
Precautions for Supplemental Restraint System (SRS) “AIR BAG” and “SEAT
BELT PRE-TENSIONER”
EFS003P3
The Supplemental Restraint System such as “AIR BAG” and “SEAT BELT PRE-TENSIONER”, used along
with a front seat belt, helps to reduce the risk or severity of injury to the driver and front passenger for certain
types of collision. This system includes seat belt switch inputs and dual stage front air bag modules. The SRS
system uses the seat belt switches to determine the front air bag deployment, and may only deploy one front
air bag, depending on the severity of a collision and whether the front occupants are belted or unbelted.
Information necessary to service the system safely is included in the SRS and SB section of this Service Man-
ual.
WA RN ING:

To avoid rendering the SRS inoperative, which could increase the risk of personal injury or death
in the event of a collision which would result in air bag inflation, all maintenance must be per-
formed by an authorized NISSAN/INFINITI dealer.

Improper maintenance, including incorrect removal and installation of the SRS, can lead to per-
sonal injury caused by unintentional activation of the system. For removal of Spiral Cable and Air
Bag Module, see the SRS section.

Do not use electrical test equipment on any circuit related to the SRS unless instructed to in this
Service Manual. SRS wiring harnesses can be identified by yellow and/or orange harnesses or
harness connectors.
Precautions for Brake SystemEFS0062U

Refer to MA-10, "RECOMMENDED FLUIDS AND LUBRICANTS" for recommended brake fluid.

Do not reuse drained brake fluid.

Be careful not to splash brake fluid on painted areas.

To clean or wash all parts of master cylinder, disc brake caliper and wheel cylinder, use clean brake fluid.

Do not use mineral oils such as gasoline or kerosene. They will ruin rubber parts of the hydraulic system.

Use flare nut wrench when removing and installing brake tube.

Always check tightening torque when installing brake lines.

Before working, turn ignition switch to OFF and disconnect con-
nectors for ABS actuator and electric unit (control unit) or battery
terminals.

Burnish the brake contact surfaces after refinishing or replacing
drums or rotors, after replacing pads or linings, or if a soft pedal
occurs at very low mileage. Refer to BR-25, "
BRAKE BURNISH-
ING PROCEDURE" .
WA RN ING:

Clean brake pads and shoes with a waste cloth, then wipe
with a dust collector.SBR6 86 C

BR-4
PREPARATION
Revision: August 20072004 QX56
PREPARATIONPFP:00002
Special Service ToolEFS0062T
The actual shapes of Kent-Moore tools may differ from those of special service tools illustrated here.
Commercial Service ToolsEFS003P5
Tool number
(Kent-Moore No.)
Tool nameDescription
—
(J-46532)
Brake and clutch pedal height measure-
ment toolMeasuring brake pedal height.
LFIA0227E
Tool nameDescription
1. Flare nut crowfoot
2. Torque wrenchRemoving and installing brake piping.
a: 10 mm (0.39 in) / 12 mm (0.47 in)
Power toolRemoving bolts, nuts, and screws.
S-NT360
PBIC0190E
PBIC0191E

BRAKE BOOSTER
BR-17
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Revision: August 20072004 QX56
BRAKE BOOSTERPFP:47200
On-Vehicle ServiceEFS003PJ
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
SBR3 65 AA

BR-22
FRONT DISC BRAKE
Revision: August 20072004 QX56
WAR NIN G:
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 PadEFS003PP
REMOVAL
1. Remove wheel and tire using power tool.
2. Remove master cylinder reservoir cap.
3. Remove lower sliding pin bolt using power tool.
4. Suspend cylinder body with a wire and remove pads, shims and retainers from torque member.
INSTALLATION
1. Apply Molykote AS880N grease between brake pad plate and shim, then attach shims to brake pads.
Refer to MA-10, "
RECOMMENDED FLUIDS AND LUBRICANTS" .
2. Attach pad retainer to torque member, then install brake pad and
shim assemblies.
CAUTION:
When attaching pad retainer, attach it firmly so that it is
flush with torque member, as shown.
3. Push pistons into cylinder body.
NOTE:
Using a disc brake piston tool (commercial service tool), etc.,
makes it easier to push in piston.
CAUTION:
By pushing in piston, brake fluid returns to master cylinder
reservoir tank. Watch the level of the surface of reservoir tank.
4. Remove wire then swing cylinder body down over brake pad assemblies.
5. Install lower sliding pin bolt and tighten to specification. Refer to BR-21, "
Components" .
6. Check brake for drag.
7. Inspect fluid level, then install master cylinder reservoir cap.
8. Install wheel and tire. Refer to WT-6, "
Rotation" .
Removal and Installation of Brake Caliper and Disc RotorEFS0062V
REMOVAL
1. Remove wheel and tire 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 union bolt as necessary and torque member bolts, then remove cylinder body and torque mem-
ber assembly.
NOTE:
Position cylinder body aside using suitable wire, as necessary.
NOTE:
When servicing cylinder body, remove sliding pin bolts and cylinder body from torque member.
4. Remove torque member, as necessary.
5. Remove disc rotor.
PFIA0273E

BR-24
FRONT DISC BRAKE
Revision: August 20072004 QX56
4. Using a flat-bladed screwdriver, remove piston seal from cylin-
der body.
CAUTION:
Be careful not to damage cylinder body inner wall.
CALIPER INSPECTION
Cylinder Body
CAUTION:

Use new brake fluid for cleaning. Do not use mineral oils such as gasoline or kerosene.

Check inside surface of cylinder body for score, rust, wear, damage or foreign materials. If any of
the above conditions are observed, replace cylinder body.

Minor damage from rust or foreign materials may be eliminated by polishing surface with a fine
emery paper. Replace cylinder body if necessary.
Torque Member
Check for wear, cracks, and damage. If damage or deformation is present, replace the affected part.
Piston
Check piston for score, rust, wear, damage or presence of foreign materials. Replace if any of the above con-
dition are observed.
CAUTION:
Piston sliding surface is plated, do not polish with emery paper even if rust or foreign materials are
stuck to sliding surface.
Sliding Pins, and Sliding Pin Boots
Check sliding pin and sliding pin boot for wear, damage, and cracks. If damage or deformation is present,
replace the affected part.
CAUTION:
Trailing/upper sliding pin must be replaced at each service.
ASSEMBLY
CAUTION:
Do not use NISSAN Rubber Grease (KRE00 00010, KRE00 00010 01) when assembling.
1. Apply clean brake fluid to new piston seal and insert seal in to
groove on cylinder body.
CAUTION:
Do not reuse piston seal.
SFIA1301E
WFIA0210E

FRONT DISC BRAKE
BR-25
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Revision: August 20072004 QX56
2. Apply brake fluid to piston and piston boot, then install piston
boot in to piston groove.
CAUTION:
Do not reuse piston boot.
3. Insert into cylinder body by hand and insert piston boot piston-side lip into piston groove.
CAUTION:
Press piston evenly and vary the pressing point to prevent cylinder body inner wall from being
rubbed.
4. Install sliding pins and sliding pin boots to torque member.
CAUTION:
Trailing/upper sliding pin must be replaced at each service.
5. Install cylinder body. Tighten sliding pin bolt to the specified torque. Refer to BR-21, "
Components" .
DISC ROTOR INSPECTION
Visual Inspection
Check surface of disc rotor for uneven wear, cracks, and serious damage. If any of them is detected, replace
applicable part.
Runout Inspection
1. Using wheel nuts, fix disc rotor to wheel hub at 2 or more positions.
2. Inspect runout using a dial gauge. (Measured at 10 mm (0.39 in)
inside the disc edge.)
NOTE:
Make sure that wheel bearing axial end play is within the specifi-
cations before measuring runout. Refer to FA X -5 , "
WHEEL
BEARING INSPECTION" .
3. If runout is outside the limit, find the minimum runout point by
shifting mounting positions of disc rotor and wheel hub by one
hole.
4. If runout still out of specification, turn rotor with on-car brake
lathe.
Thickness Inspection
Using a micrometer, check thickness of disc rotor. If thickness is
either at or below the wear limit, or exceeds maximum uneven wear,
replace disc rotor.
BRAKE BURNISHING PROCEDURE
Burnish brake contact surface according to the following procedure after refinishing or replacing rotors, after
replacing pads, or if a soft pedal occurs at very low mileage.
WFIA0211E
Runout limit (on vehicle) : 0.04 mm (0.0016 in)
BRA0013D
Standard thickness : 26.0 mm (1.024 in)
Repair limit thickness : 24.5 mm (0.965 in)
Maximum uneven wear
(Measured at 8 positions): 0.015 mm (0.0006 in)
SBR0 20 B