Ford Falcon. Manual — part 18

100-04-44

Noise, Vibration and Harshness

100-04-44

DIAGNOSIS AND TESTING (Continued)

Test Step

Result / Action to Take

I5

RADIAL RUNOUT CHECK ON THE TIRE

Measure the radial runout of the wheel and tyre assembly. A typical

Yes

specification for total radial runout is 1.15mm (0.059inch).

Go to I8.

No

Go to I6.

Is the radial runout within specifications?

I6

RADIAL RUNOUT CHECK ON THE WHEEL

Measure the radial runout of the wheel. A typical specification for total

Yes

radial runout is 1.14mm (0.045 inch).

INSTALL a new tyre. TEST the system for
normal operation.

Is the radial runout within specifications?

No

Go to I7.

I7

CHECK THE HUB/BRAKE DISC OR DRUM PILOT

RUNOUT OR BOLT CIRCLE RUNOUT

Measure the pilot or bolt circle runout. A typical specification for radial

Yes

runout is:

INSTALL a new wheel. TEST the system for
normal operation.

pilot runout— less than 0.15 mm (0.006 inch)

bolt circle runout— less than 0.38 mm (0.015 inch)

No

REPAIR or INSTALL new components as

Is the radial runout within specifications?

necessary. REFER to 204-01 for the front
suspension or 204-02 for the rear suspension.

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Noise, Vibration and Harshness

100-04-45

DIAGNOSIS AND TESTING (Continued)

Test Step

Result / Action to Take

I8

LATERAL RUNOUT CHECK ON THE TIRE

Measure the lateral runout of the wheel and tyre assembly. A typical

Yes

specification for total lateral runout is 2.5mm (0.098inch).

Wheel and tyres are OK. CONDUCT diagnosis
on other suspect systems.

No

Go to I9.

Is the lateral runout within specifications?

I9

LATERAL RUNOUT CHECK ON THE WHEEL

Measure the lateral runout of the wheel. A typical specification for

Yes

total radial runout is 1.2mm (0.047inch).

INSTALL a new tyre. TEST the system for
normal operation.

Is the lateral runout within specifications?

No

Go to I10.

I10

CHECK THE FLANGE FACE LATERAL RUNOUT

Measure the flange face lateral runout. A typical specification for

Yes

lateral runout is:

INSTALL a new wheel. TEST the system for
normal operation.

hub/brake disc— less than 0.13mm (0.005inch)

axle shaft— less than 0.25 mm (0.010 inch)

No

REPAIR or INSTALL new components as

Is the lateral runout within specifications?

necessary. REFER to Section 204-01 for the
front suspension or Section 204-02 for the rear
suspension.

PINPOINT TEST J : HIGH SPEED SHAKE OR SHIMMY

Test Step

Result / Action to Take

J1

CHECK FOR FRONT WHEEL BEARING ROUGHNESS

Chock the rear wheels.

Yes

INSPECT the wheel bearings. REPAIR as

Raise and support the front end of the vehicle so that the front wheel

necessary. TEST the system for normal

and tyre assemblies can spin. Refer to Section 100-02 .

operation.

Spin the front tyres by hand.

No

Do the wheel bearings feel rough?

Go to J2.

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Noise, Vibration and Harshness

100-04-46

DIAGNOSIS AND TESTING (Continued)

Test Step

Result / Action to Take

J2

CHECK THE END PLAY OF THE FRONT WHEEL

BEARINGS

Check the end play of the front wheel bearings.

Yes

Go to J3.

Is the end play OK?

No

ADJUST or REPAIR as necessary. TEST the
system for normal operation.

J3

MEASURE THE LATERAL RUNOUT AND THE RADIAL

RUNOUT OF THE FRONT WHEELS ON THE VEHICLE

Measure the lateral runout and the radial runout of the front wheels on

Yes

the vehicle. Go to Pinpoint Test I.

Go to J4.

Are the measurements within specifications?

No

INSTALL new wheels as necessary and
BALANCE the assembly. TEST the system for
normal operation.

J4

MEASURE THE LATERAL RUNOUT OF THE FRONT

TIRES ON THE VEHICLE

Measure the lateral runout of the front tyres on the vehicle. Go to

Yes

Pinpoint Test I.

Go to J5.

Is the runout within specifications?

No

INSTALL new tyres as necessary and
BALANCE the assembly. TEST the system for
normal operation.

J5

MEASURE THE RADIAL RUNOUT OF THE FRONT

TIRES ON THE VEHICLE

Measure the radial runout of the front tyres on the vehicle. Go to

Yes

Pinpoint Test I.

BALANCE the front wheel and tyre assemblies.
If any tyre cannot be balanced, INSTALL a new

Is the runout within specifications?

tyre. TEST the system for normal operation.

No

Go to J6.

J6

MATCH MOUNT THE TIRE AND WHEEL ASSEMBLY

Mark the high runout location on the tyre and also on the wheel.

Yes

Break the assembly down and rotate the tyre 180 degrees (halfway

BALANCE the assembly. TEST the system for

around) on the wheel. Inflate the tyre and measure the radial runout.

normal operation.

Is the runout within specifications?

No

If the high spot is not within 101.6 mm (4 inches)
of the first high spot on the tyre, Go to J7.

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Noise, Vibration and Harshness

100-04-47

DIAGNOSIS AND TESTING (Continued)

Test Step

Result / Action to Take

J7

MEASURE THE WHEEL FLANGE RUNOUT

Dismount the tyre and mount the wheel on a wheel balancer.

Yes

Measure the runout on both wheel flanges. Go to Pinpoint Test I.

LOCATE and MARK the low spot on the wheel.
INSTALL the tyre, matching the high spot on the

Is the runout within specifications?

tyre with the low spot on the wheel. BALANCE
the assembly. TEST the system for normal
operation. If the condition persists, Go to J8.

No

INSTALL a new wheel. CHECK the runout on
the new wheel. If the new wheel is within limits,
LOCATE and MARK the low spot. INSTALL the
tyre, matching the high spot on the tyre with the
low spot on the wheel. BALANCE the assembly.
TEST the system for normal operation. If the
condition persists, Go to J8.

J8

CHECK FOR VIBRATION FROM THE FRONT OF THE

VEHICLE

Yes

WARNING:

If only one drive wheel is allowed to rotate, speed SUBSTITUTE known good wheel and tyre

must be limited to 55 km/h (34 mph) using the speedometer reading,

assemblies as necessary. TEST the system for

since actual wheel speed will be twice that indicated on the

normal operation.

speedometer. Exceeding a speed of 55 km/h (34 mph) or allowing the

No

drive wheel to hang unsupported can result in tyre disintegration or

For front wheel drive vehicles, check the

differential failure, which can cause serious personal injury and

driveline components. TEST the system for

extensive vehicle damage.

normal operation. For rear wheel drive vehicles,

Spin the front wheel and tyre assemblies with a wheel balancer while

Go to J9.

the vehicle is raised on a hoist. Feel for vibration in the front fender or
while seated in the vehicle.

Is the vibration present?

J9

CHECK FOR VIBRATION FROM THE REAR OF THE

VEHICLE

Yes

WARNING:

If only one drive wheel is allowed to rotate, speed Go to J10.

must be limited to 55 km/h (34 mph) using the speedometer reading,

No

since actual wheel speed will be twice that indicated on the

TEST the system for normal operation.

speedometer. Exceeding a speed of 55 km/h (34 mph) or allowing the
drive wheel to hang unsupported can result in tyre disintegration or
differential failure, which can cause serious personal injury and
extensive vehicle damage.

Chock the front wheels.

Raise and support the rear end of the vehicle so that the rear wheel
and tyre assemblies can spin. Refer to Section 100-02 .

Engage the drivetrain and carefully accelerate the drive wheels while
checking for vibration.

Is the vibration present?

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