Brake fluid ISUZU AXIOM 2002 Service User Guide

5A±9
BRAKE CONTROL SYSTEM
Brake Release
At the end of the anti-lock stop, when the brake pedal is
released, the pump will remain running for a short time to
help drain any fluid from the accumulators. As this fluid
returns into the system, the spring forces the piston back
to its original position.
The isolation valve opens and fluid may return to the
master cylinder. Conventional braking is then resumed.
C05RW013
Legend
(1) Brake
(2) Master Cylinder

5A±10BRAKE CONTROL SYSTEM
System Components
Electronic Hydraulic Control Unit (EHCU), three Wheel
Speed Sensors, Warning Light, and G-sensor.
Electronic Hydraulic Control Unit (EHCU)
The EHCU consists of ABS control circuits, fault detector,
and a fail-safe. The signal received from each sensor
activates the hydraulic unit accordingly and cancels the
ABS to return to normal braking if a malfunction occurs in
the ABS system.
The EHCU has a self-diagnosing function which can
indicate faulty circuits during diagnosis.
The EHCU is mounted on the engine compartment rear
right side. It consists of a Motor, Plunger Pump, Solenoid
Valves.
Solenoid Valves: Reduces or holds the caliper fluid
pressure for each front disc brake or both rear disc brakes
according to the signal sent from the EHCU.
Reservoir: Temporarily holds the brake fluid that returns
from the front and rear disc brake caliper so that pressure
of front disc brake caliper can be reduced smoothly.
Plunger Pump: Feeds the brake fluid held in the reservoir
to the master cylinder.
Motor: Drives the pump according to the signal from
EHCU.
Check Valve: Controls the brake fluid flow.
ABS Warning Light
821R200015Vehicles equipped with the Anti-lock Brake System have
an amber ªABSº warning light in the instrument panel.
The ªABSº warning light will illuminate if a malfunction in
the Anti-lock Brake System is detected by the Electronic
Hydraulic Control Unit (EHCU).In case of an electronic
malfunction, the EHCU will turn ªONº the ªABSº warning
light and disable the Anti-lock braking function.
The ªABSº light will turn ªONº for approximately three
seconds after the ignition switch is turned to the ªONº
position.If the ªABSº light stays ªONº after the ignition switch is
turned to the ªONº position, or comes ªONº and stays
ªONº while driving, the Anti-lock Brake System should be
inspected for a malfunction according to the diagnosis
procedure.
Wheel Speed Sensor
It consists of a sensor and a rotor. The sensor is attached
to the knuckle on the front wheels and to the rear axle
case on the rear differential.
The front sensor rotor is attached to the each brake rotor
by bolts.
The rear rotor is press-fit in the differential case.
The magnetic flux generated from electrodes magnetized
by a magnet in the sensor varies due to rotation of the
rotor, and the electromagnetic induction generates
alternating voltage in the coil. This voltage draws a ªsine
curveº with the frequency proportional to rotor speed and
it allows detection of wheel speed.
G-Sensor
The G-sensor installed inside the EHCU detects the
vehicle deceleration speed and sends a signal to the
EHCU. In 4WD operation, all four wheels may be
decelerated in almost the same phase, since all wheels
are connected mechanically.
This tendency is noticeable particularly on roads with low
friction coefficient, and the ABS control is adversely
affected.
The G-sensor judges whether the friction coefficient of
road surface is low or high, and changes the EHCU's
operating system to ensure ABS control.
Normal and Anti-lock Braking
Under normal driving conditions, the Anti-lock Brake
System functions the same as a standard power assisted
brake system. However, with the detection of wheel
lock-up, a slight bump or kick-back will be felt in the brake
pedal. This pedal ªbumpº will be followed by a series of
short pedal pulsations which occurs in rapid succession.
The brake pedal pulsation will continue until there is no
longer a need for the anti-lock function or until the vehicle
is stopped. A slight ticking or popping noise may be heard
during brake applications when the Anti-lock features is
being used.
When the Anti-lock feature is being used, the brake pedal
may rise even as the brakes are being applied. This is
also normal. Maintaining a constant force on the pedal
will provide the shortest stopping distance.
Brake Pedal Travel
Vehicles equipped with the Anti-lock Brake System may
be stopped by applying normal force to the brake pedal.
Although there is no need to push the pedal beyond the
point where it stops or holds the vehicle, by applying more
force the pedal will continue to travel toward the floor.
This extra brake pedal travel is normal.

5A±11
BRAKE CONTROL SYSTEM
Acronyms and Abbreviations
Several acronyms and abbreviations are commonly used
throughout this section:
ABS
Anti-lock Brake System
CIM
Coil Integrated Module
CKT
Circuit
DLC
Data Link Connector
EHCU
Electronic Hydraulic Control Unit
FL
Front Left
FR
Front Right
GEN
Generator
H/U
Hydraulic Unit
MV
Millivolts
RR
Rear
RPS
Revolution per Second
VDC
DC Volts
VA C
AC Volts
W/L
Warning Light
WSS
Wheel Speed Sensor
General Diagnosis
General Information
ABS troubles can be classified into two types, those
which can be detected by the ABS warning light and those
which can be detected as a vehicle abnormality by the
driver.
In either case, locate the fault in accordance with the
ªBASIC DIAGNOSTIC FLOWCHARTº and repair.
Please refer to
Section 5C for the diagnosis of
mechanical troubles such as brake noise, brake judder
(brake pedal or vehicle vibration felt when braking),
uneven braking, and parking brake trouble.
ABS Service Precautions
Required Tools and Items:

Box Wrench

Brake Fluid

Special ToolSome diagnosis procedures in this section require the
installation of a special tool.
J-39200 High Impedance Multimeter
When circuit measurements are requested, use a circuit
tester with high impedance.
Computer System Service Precautions
The Anti-lock Brake System interfaces directly with the
Electronic Hydraulic Control Unit (EHCU) which is a
control computer that is similar in some regards to the
Powertrain Control Module. These modules are designed
to withstand normal current draws associated with
vehicle operation. However, care must be taken to avoid
overloading any of the EHCU circuits. In testing for opens
or shorts, do not ground or apply voltage to any of the
circuits unless instructed to do so by the appropriate
diagnostic procedure. These circuits should only be
tested with a high impedance multimeter (J-39200) or
special tools as described in this section. Power should
never be removed or applied to any control module with
the ignition in the ªONº position.
Before removing or connecting battery cables, fuses or
connectors, always turn the ignition switch to the ªOFFº
position.
General Service Precautions
The following are general precautions which should be
observed when servicing and diagnosing the Anti-lock
Brake System and/or other vehicle systems. Failure to
observe these precautions may result in Anti-lock Brake
System damage.

If welding work is to be performed on the vehicle using
an electric arc welder, the EHCU and valve block
connectors should be disconnected before the
welding operation begins.

The EHCU and valve block connectors should never
be connected or disconnected with the ignition ªONº .

If only the rear wheels are rotated using jacks or drum
tester, the system will diagnose a speed sensor
malfunction and the ªABSº warning light will
illuminate. But actually no trouble exists. After
inspection stop the engine once and re-start it, then
make sure that the ªABSº warning light does not
illuminate.
If the battery has been discharged
The engine may stall if the battery has been completely
discharged and the engine is started via jumper cables.
This is because the Anti-lock Brake System (ABS)
requires a large quantity of electricity. In this case, wait
until the battery is recharged, or set the ABS to a
non-operative state by removing the fuse for the ABS
(50A). After the battery has been recharged, stop the
engine and install the ABS fuse. Start the engine again,
and confirm that the ABS warning light does not light.
Note on Intermittents
As with virtually any electronic system, it is difficult to
identify an intermittent failure. In such a case duplicating
the system malfunction during a test drive or a good
description of vehicle behavior from the customer may be
helpful in locating a ªmost likelyº failed component or

5A±16BRAKE CONTROL SYSTEM
DATA LIST
The data displayed by DATA LIST are as follows:
Display
ContentOK/NG Criteria for Data
Front Left Wheel Speed
Front Right Wheel Speed
Rear Wheel Speedskm/h (MPH)
Start the vehicle and make sure of linear change in
each wheel speed.

Turn each wheel by hand and make sure that each
speed data change.
Warning LampON/OFF
To be OFF usually
ABS StateON/OFF
To be OFF usually
ABS RelayActive/Inactive
To be Active usually
4 Wheel DriveActive/Inactive
2WD: Inactive

4WD: Active
Brake SwitchActive/Inactive
Inactive (Released)

Active (Pressed)
Brake Fluid LevelNormal or not
To be Normal usually
Return PumpActive/Inactive
To be Inactive usually
DRP (Dynamic Rear
Proportioning)Active/Inactive
To be Inactive usually
Rear Dump Valve CommandedActive/Inactive
To be Inactive usually
Rear Dump Valve Feedback
Rear Isolation Valve
Commanded
Rear Isolation Valve Feedback
FL Dump Valve CommandedActive/Inactive
To be Inactive usually
FL Dump Valve Feedback
FL Isolation Valve Commanded
FL Isolation Valve Feedback
FR Dump Valve CommandedActive/Inactive
To be Inactive usually
FR Dump Valve Feedback
FR Isolation Valve
Commanded
FR Isolation Valve Feedback
G±SensorVoltage
2.50V when vehicle is stopped
Battery VoltageVoltage
Between 10±16.9V

5A±23
BRAKE CONTROL SYSTEM
Basic Inspection Procedure
1. Basic Inspection of Service Brake
StepActionYe sNo
1Is the fluid level normal?
Go to Step 2
Replenish with
fluid
Go to
Step 2
2Does fluid leak?Repair
Go to
Step 3Go to Step 3
3Is the booster functioning properly?
Go to Step 4
Repair
Go to
Step 4
4Is the pad and rotor within specs?
Go to Step 5
Repair
Go to
Step 5
5Reconnect all components. Ensure all component are properly
mounted.
Was this step finished?
FinishedGo to Step 5
2. Ground Inspection
StepActionYe sNo
1Is there good contact with the ABS ground points?
Go to Step 2
Repair
Go to
Step 2
2Reconnect all components. Ensure that all component are
properly mounted.
FinishedGo to Step 2

5C±1 POWER±ASSISTED BRAKE SYSTEM
AXIOM (Vehicles Produced Before July/31/2001)
BRAKES
POWER-ASSISTED BRAKE SYSTEM
CONTENTS
Service Precaution 5C±2. . . . . . . . . . . . . . . . . . . . . .
General Description 5C±2. . . . . . . . . . . . . . . . . . . . .
Diagnosis 5C±6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
General Diagnosis 5C±7. . . . . . . . . . . . . . . . . . . . . . .
Hydraulic Brakes 5C±10. . . . . . . . . . . . . . . . . . . . . . . .
Filling Master Cylinder Reservoir 5C±10. . . . . . . .
Deterioration of Brake Fluid 5C±10. . . . . . . . . . . . .
Leakage of Brake Fluid 5C±10. . . . . . . . . . . . . . . . .
Bleeding Brake Hydraulic System 5C±10. . . . . . . .
Flushing Brake Hydraulic System 5C±11. . . . . . . .
Brake Pipes and Hoses 5C±11. . . . . . . . . . . . . . . .
Brake Hose Inspection 5C±11. . . . . . . . . . . . . . . . .
Front Caliper Brake Hose 5C±12. . . . . . . . . . . . . . . .
Front Caliper Brake Hose and Associated
Parts 5C±12. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Removal 5C±12. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 5C±12. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Rear Axle Brake Hose 5C±13. . . . . . . . . . . . . . . . . . .
Rear Axle Brake Hose and Associated
Parts 5C±13. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Removal 5C±13. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 5C±13. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Brake Pipe 5C±14. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Removal 5C±14. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 5C±14. . . . . . . . . . . . . . . . . . . . . . . . . . . .
P & B (Proportioning and Bypass) Valve 5C±15. . . .
P & B (Proportioning and Bypass) Valve
Sectional View 5C±15. . . . . . . . . . . . . . . . . . . . . . . .
Removal 5C±15. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 5C±15. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Main Data and Specifications 5C±16. . . . . . . . . . . . .
Brake Pedal 5C±17. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Checking Pedal Height 5C±17. . . . . . . . . . . . . . . . .
Checking Pedal Travel 5C±17. . . . . . . . . . . . . . . . .
Brake Pedal and Associated Parts 5C±18. . . . . . .
Removal 5C±18. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 5C±18. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Stoplight Switch 5C±19. . . . . . . . . . . . . . . . . . . . . . . . .
Parts Location 5C±19. . . . . . . . . . . . . . . . . . . . . . . .
Removal 5C±19. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 5C±19. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Main Data and Specifications 5C±20. . . . . . . . . . . . .
Fluid Reservoir Tank 5C±21. . . . . . . . . . . . . . . . . . . . .
Fluid Reservoir Tank and Associated Parts 5C±21Removal 5C±21. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 5C±21. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Master Cylinder Assembly 5C±22. . . . . . . . . . . . . . . .
Master Cylinder Assembly and Associated
Parts 5C±22. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Removal 5C±22. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Inspection and Repair 5C±22. . . . . . . . . . . . . . . . . .
Installation 5C±23. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Main Data and Specifications 5C±24. . . . . . . . . . .
Special Tools 5C±24. . . . . . . . . . . . . . . . . . . . . . . . . .
Vacuum Booster Assembly 5C±25. . . . . . . . . . . . . . .
Vacuum Booster Assembly and Associated
Parts 5C±25. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Removal 5C±25. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Inspection and Repair 5C±26. . . . . . . . . . . . . . . . . .
Installation 5C±26. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Exterior Components 5C±28. . . . . . . . . . . . . . . . . . . .
Exterior Components and Associated Parts 5C±28
Removal 5C±28. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Inspection and Repair 5C±29. . . . . . . . . . . . . . . . . .
Installation 5C±29. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Vacuum Booster Overhaul 5C±29. . . . . . . . . . . . . . . .
Vacuum Booster 5C±29. . . . . . . . . . . . . . . . . . . . . . .
Main Data and Specifications 5C±30. . . . . . . . . . . . .
Special Tools 5C±31. . . . . . . . . . . . . . . . . . . . . . . . . . .
Front Disc Brake Pads 5C±32. . . . . . . . . . . . . . . . . . .
Front Disc Brake Pads Inspection 5C±32. . . . . . . .
Front Disc Brake Pads and Associated
Parts 5C±32. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Removal 5C±33. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 5C±33. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Front Disc Brake Rotor 5C±35. . . . . . . . . . . . . . . . . . .
Inspection 5C±35. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Replacing Brake Rotors 5C±35. . . . . . . . . . . . . . . .
Refinishing Brake Rotors 5C±35. . . . . . . . . . . . . . .
Front Disc Brake Caliper Assembly 5C±36. . . . . . . .
Front Disc Brake Caliper Assembly and
Associated Parts 5C±36. . . . . . . . . . . . . . . . . . . . . .
Removal 5C±37. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 5C±37. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Front Disc Brake Caliper 5C±39. . . . . . . . . . . . . . . . .
Front Disc Brake Caliper Disassembled
View 5C±39. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Disassembly 5C±39. . . . . . . . . . . . . . . . . . . . . . . . . .

5C±3 POWER±ASSISTED BRAKE SYSTEM
The master cylinder contains two pistons that supply the
hydraulic pressure for a dual±circuit braking system. The
primary piston provides the fluid pressure to the front
brakes, while the secondary piston provides the fluid
pressure to the rear brakes. If the pressure is lost from
either system, the remaining system will function to stop
the vehicle.CAUTION:
1. The master cylinder is not repairable. If found
defective, it must be replaced as a complete
assembly.
2. If any hydraulic component is removed or
disconnected, it may be necessary to bleed all or
part of the brake system. (Refer to
Bleeding Brake
Hydraulic System
in this section.)
3. The torque values specified are for dry,
unlubricated fasteners.
4. Perform service operations on a clean bench free
from all mineral oil materials.
Brake Booster
331RS001
This booster is a tandem vacuum unit with a diaphragm
effective diameter 205mm (8.072 in) + 230mm (9.056 in).
In normal operating mode, with the service brakes in the
released position, the tandem vacuum booster operates
with vacuum on both sides of its diaphragms. When the
brakes are applied, air at atmospheric pressure is
admitted to both sides of the diaphragm to provide the
power assist. When the service brake is released, the
atmospheric air is shut off from both sides of the
diaphram. The air is then drawn from the booster through
the vacuum check valve to the vacuum source.CAUTION:
1. If any hydraulic component is removed or
disconnected, it may be necessary to bleed all or
part of the brake system.
2. The torque values specified are for dry,
unlubricated fasteners.
3. The vacuum booster is not repairable and must be
replaced as complete assembly.

5C±4
POWER±ASSISTED BRAKE SYSTEM
Disc Brake
Front Disc Brake
A05RW001
Rear Disc Brake (4y4 Model)
A05RW002
The disc brake assembly consists of a caliper, piston,
rotor, pad assembly and support bracket. The caliper
assembly has a single bore and is mounted to the support
bracket with two mounting bolts. The support bracket
allows the caliper to move laterally against the rotor. The
caliper is a one±piece casting with the inboard side
containing the piston bore. A square cut rubber seal is
located in a groove in the piston bore which provides the
hydraulic seal between the piston and the cylinder wall.
NOTE:
1. Replace all components included in repair kits used to
service this caliper.
2. Lubricate rubber parts with clean brake fluid to ease
assembly.3. If any hydraulic component is removed or
disconnected, it may be necessary to bleed all or part
of the brake system.
4. Replace pads in axle sets only.
5. The torque values specified are for dry, unlubricated
fasteners.
6. Perform the service operation on a clean bench free
from all mineral oil materials.
Operation
Hydraulic pressure, created by applying the brake pedal,
is converted by the caliper to a stopping force. This force
creates a clamping action of the piston pressing towards
the rotors (outward) and the caliper slides inward toward
the vehicle. This clamping action forces the linings
against the rotor, creating friction to stop the vehicle.

5C±6
POWER±ASSISTED BRAKE SYSTEM
Diagnosis
Road Testing The Brakes
Brake Test
Brakes should be tested on a dry, clean, reasonably
smooth and level roadway. A true test of brake
performance cannot be made if the roadway is wet,
greasy or covered with loose dirt where all tires do not grip
the road equally. Testing will also be adversely affected if
the roadway is crowned so as to throw the weight of the
vehicle toward wheels on one side or if the roadway is so
rough that wheels tend to bounce. Test the brakes at
different vehicle speeds with both light and heavy pedal
pressure; however, avoid locking the wheels and sliding
the tires. Braking without locking the tires will stop the
vehicle in less distance than braking to a skid (which has
no brake efficiency). More tire to road friction is present
while braking without locking the tires than braking to a
skid.
The standard brake system is designed and balanced to
avoid locking the wheels except at very high deceleration
levels.
It is designed this way because the shortest stopping
distance and best control is achieved without brake
lock±up.
Because of high deceleration capability, a firmer pedal
may be felt at higher deceleration levels.
External Conditions That Affect Brake Performance
1. Tires: Tires having unequal contact and grip on the
road will cause unequal braking. Tires must be
equally inflated, identical in size, and the thread
pattern of right and left tires must be approximately
equal.
2. Vehicle Loading: A heavily loaded vehicle requires
more braking effort.
3. Wheel Alignment: Misalignment of the wheels,
particularly in regard to excessive camber and caster,
will cause the brakes to pull to one side.
Brake Fluid Leaks
With engine running at idle and the transmission in
ªNeutralº, depress the brake pedal and hold a constant
foot pressure on the pedal. If pedal gradually falls away
with the constant pressure, the hydraulic system may be
leaking.
Check the master cylinder fluid level. While a slight drop in
the reservoir level will result from normal lining wear, an
abnormally low level in reservoir indicates a leak in the
system. The hydraulic system may be leaking internally
as well as externally. Refer to
Master Cylinder Inspection.
Also, the system may appear to pass this test but still
have slight leakage. If fluid level is normal, check the
vacuum booster push rod length. If an incorrect length
push rod is found, adjust or replace the push rod. Check
the brake pedal travel and the parking brake adjustment.
When checking the fluid level, the master cylinder fluid
level may be lower than the ªMAXº mark if the front and
rear linings are worn. This is normal.
Warning Light Operation
When the ignition switch is in the START position, the
ªBRAKEº warning light should turn on and go off when the
ignition switch returns to the ON position.
The following conditions will activate the ªBRAKEº light:
1. Parking brake applied. The light should be on
whenever the parking brake is applied and the ignition
switch is on.
2. Low fluid level. A low fluid level in the master cylinder
will turn the ªBRAKEº light on.
3. During engine cranking the ªBRAKEº light should
remain on. This notifies the driver that the warning
circuit is operating properly.

5C±8
POWER±ASSISTED BRAKE SYSTEM
Condition CorrectionPossible cause
Excessive Brake Pedal TravelAir in hydraulic circuit.Bleed the hydraulic circuit.
Level of brake fluid in the reservoir
too low.Replenish brake fluid reservoir to
specified level and bleed hydraulic
circuit as necessary.
Master cylinder push rod clearance
excessive.Adjust
Leakage in hydraulic system.Correct or replace defective parts.
Brake DragMaster cylinder pistons not returning
correctly.Adjust the stop light switch and
vacuum booster push rod. If
necessary, rebuild.
Restricted brake pipes or hoses.Check for soft hoses or damaged
pipes, and replace with new hoses
and new double±walled steel brake
piping.
Parking brake maladjusted.Adjust
Parking brake lining clearance
insufficient.Adjust
Brake pedal free play insufficient.Adjust the brake pedal height or
power cylinder operating rod.
Piston in the master cylinder sticking.Replace
Piston in the disc brake caliper
sticking.Replace piston seals.
Brake pads sticking in caliper.Clean
Return spring weakened.Replace
Parking brake binding.Overhaul the parking brakes and
correct.
Front hub bearing preload incorrect.Adjust or replace.
Parking brake shoes not returning.Correct or replace the brake back
plate and brake shoe as necessary.
Obstructions in hydraulic circuit.Clean
Rotor warped excessively.Grind or replace.
Rear brake drum distorted.Grind or replace.
Parking cable sticking.Grind or replace.
Grabbing or Uneven Braking Action
(All conditions listed under ªPullsº)Malfunctioning vacuum booster.Check operation and correct as
necessary.
Binding brake pedal mechanism.Check and lubricate, if necessary.
Corroded caliper assembly.Clean and lubricate.
Brake NoisyBrake pads are worn.Replace
Brake pads are hardened.Replace
Brake pads are in poor contact with
rotor.Correct
Brake disc(s) warped, worn or
damaged.Grind or replace.
Disc brake anti±squeak shims
fatigued.Replace
Front hub bearings are loose or
preload is incorrect.Adjust or replace.
Brake disc is rusted.Grind or replace.