- Raise and support the vehicle. Refer to
Lifting and Jacking the Vehicle
.
- Remove the tyre and wheel assembly from the vehicle. Refer to
Tire and Wheel Removal and Installation
.
Important: The wheel must be mounted on the spin-type
wheel balancer in accordance with manufacturers instructions.
- Install the wheel on a spin-type wheel balancer.
Important: Wrapping the tread with tape allows for a
smooth and accurate reading of radial runout to be obtained.
- Wrap the circumference of each tyre with tape (1) in the center of the
tread area.
- Position a dial indicator fitted with a roller, on the taped portion of
the tyre tread perpendicular to the surface.
- Slowly rotate the tyre and wheel assembly one complete revolution in order
to find the wheel high point.
- Mark the location of the high point (3) on the
tyre (4).
- Place a reference mark (2) on the tyre sidewall at the location
of the valve stem (5).
• | Always refer to the valve stem (5) as the 12 O'clock position. |
• | Refer to the location of the high point (3) by its clock position
on the wheel (1), relative to the valve stem (5). |
Important: Do not dismount the tyre from the wheel.
- Mount the tyre and wheel assembly on a tyre changing machine and break down
the bead.
Important: lubricate the bead area in order to easily
rotate the tyre on the wheel.
- Rotate the tyre 180 degrees on the rim so that the valve stem reference
mark (3) is now at the 6 O'clock position in relation to the valve stem (1).
- Inflate the tyre and seat the bead, closely inspect each tyre for correct
and even bead seating.
Important: The wheel must be mounted on the spin-type
wheel balancer in accordance with manufacturers instructions.
- Install the wheel on a spin-type wheel balancer.
- Position a dial indicator fitted with a roller, on the taped portion of
the tyre tread perpendicular to the surface.
- Slowly rotate the tyre and wheel assembly one complete revolution in order
to find the wheel high point.
Important: After remounting a tyre to a wheel or after
replacing a tyre and/or a wheel, remeasure the tyre and wheel assembly runout in order
to verify that the runout has been reduced and is within tolerance. Ensure that the
tyre and wheel assembly is balanced before installing to the vehicle.
- Measure the wheel and tyre assembly runout.
- Mark the new location of the assembly runout high point on the tyre.
- If the assembly runout has been reduced and is within tolerance, no further
steps are necessary. Balance the tyre and wheel assembly, then install the assembly
to the vehicle. Refer to the following:
- If the clock location of the high point remained at or near the original
clock location of the high point (2) and the assembly runout has not been reduced,
the wheel is the major contributor to the assembly runout concern. Replace the wheel.
Refer to
Tire Dismounting and Mounting
and
Replacement Wheels Description
.
- If the clock location of the high point has moved, however
the assembly runout has not been reduced, perform the following steps:
19.1. | If the clock location of the high point (2) is now at or near a
position 180 degrees from the original clock location of the high point (1),
the tyre is the major contributor to the assembly runout concern. Replace the tyre.
Refer to
Tire Dismounting and Mounting
. |
19.2. | If the clock location of the high point is now between the original high
point position and the opposite extreme, then both the tyre and the wheel are contributing
to the assembly runout concern. Continue rotating the tyre in relation to the wheel
and remeasuring the assembly runout until the lowest amount of runout is achieved.
If the lowest amount of runout achieved is not within tolerance measure the off vehicle
tyre and wheel runout, refer to
Tire and Wheel Assembly Runout Measurement - On-Vehicle
in Tires and Wheels, in order to isolate
the tyre or wheel as the cause of the runout concern. |