Tire And Wheel RUNOUT/Match Mounting

WARNING: This page is about a different car, the 2007 Chrysler PT Cruiser. However, it is still accessible from the selected car via links, so may be relevant.

Fig 1: Radial Runout Measurement

Courtesy of CHRYSLER LLC

1 - MASKING TAPE

2 - DIAL INDICATOR

System Radial Runout. This on-the-vehicle system check will measure the radial runout including the hub, wheel and tire.
- Raise vehicle so tires clear floor. Refer to STANDARD PROCEDURE .
- Apply masking tape around the circumference of the tire in the locations to be measured (1). Do not overlap the tape.
- Check system runout using Dial Indicator Set, Special Tool C-3339A with 25-W wheel or equivalent. Place the end of the indicator against each taped area (one at a time) (2) and rotate the tire and wheel. System radial runout should not exceed 0.76 mm (0.030 inch) with no tread "dips" or "steps." Tread "dips" and "steps" can be identified by spikes of the dial indicator gauge. See Fig 1.
  1. Tread "dips"; Rapid decrease then increase in dial indicator reading over 101.6 mm (4.0 inch) of tread circumference.
  2. Tread "steps"; Rapid decrease or increase in dial indicator reading over 101.6 mm (4.0 inch) of tread circumference.
- If system runout is excessive, re-index the tire and wheel assembly on the hub. Remove assembly from vehicle and install it back on the hub two studs over from original mounting position. If re-indexing the tire and wheel assembly corrects or reduces system runout, check hub runout and repair as necessary. Refer to DIAGNOSIS AND TESTING .
- If system runout is still excessive, continue with this diagnosis and testing procedure.

Tire and Wheel Assembly Radial Runout. This radial runout check is performed with the tire and wheel assembly off the vehicle.

Remove tire and wheel assembly from vehicle and install it on a suitable wheel balancer.

Fig 2: Radial Runout Measurement

Courtesy of CHRYSLER LLC

1 - MASKING TAPE

2 - DIAL INDICATOR

Check system runout using Dial Indicator Set, Special Tool C-3339A with 25-W wheel or equivalent. Place the end of the indicator against each taped area (one at a time) and rotate the tire and wheel. Radial runout should not exceed 0.76 mm (0.030 inch) with no tread "dips" or "steps." Tread "dips" and "steps" can be identified by spikes of the dial indicator gauge.

Fig 3: Marking Tire And Wheel To Indicate High Spot

Courtesy of CHRYSLER LLC

If runout exceeds limits, mark the original location of the tire on the wheel at the valve stem (1)(4). Also, mark the tire and wheel to indicate the original high spot (2) of the assembly and record the runout measurement.
If runout exceeds limits, the tire will need to be dismounted from the wheel to verify wheel vs. tire contribution. Refer to Wheel Runout below.

Lateral Runout. Lateral runout for the vehicle system as well as the tire and wheel assembly should be less than 0.76 mm (0.030 inch). The same procedure and theory described for radial runout can also be applied to identify and reduce lateral runout.

Wheel Runout. This runout check is performed as follows:

Dismount the tire from the wheel.
Mount the wheel back on the wheel balancer.

Fig 4: Checking Radial Runout At Center Line Of Tread

Courtesy of CHRYSLER LLC

Measure radial runout of the wheel at the tire bead seat (1, 6). Runout should not exceed the specification limit listed in the following table. Replace the wheel if it exceeds the limit.

Fig 5: Checking Lateral Runout At Shoulder Of Tire

Courtesy of CHRYSLER LLC

Measure lateral runout of the wheel at the tire bead seat (1, 6). Runout should not exceed the specification limit listed in the following table. Replace the wheel if it exceeds the limit.

WHEEL RUNOUT LIMITS

WHEEL TYPE	RADIAL RUNOUT	LATERAL RUNOUT
Aluminum Wheel	0.50 mm (0.020 inch)	0.50 mm (0.020 inch)
Steel Wheel	0.62 mm (0.024 inch)	0.80 mm (0.031 inch)

Match Mounting. If the wheel runout is within specifications, tire and wheel assembly runout can be improved by re-indexing (match mounting) the tire to the wheel as described below.
- Remount the tire on the rim 180 degrees from its original location. Ensure the tire bead is properly seated.
- Re-measure the total runout. Mark the tire at the high spot and record the measurement.
If runout is still excessive, perform the following:
1. If the new high spot is within 102 mm (4.0 inch) of the first high spot on the tire, replace the tire.
2. If the new high spot is within 102 mm (4.0 inch) of the first high spot on the wheel, the wheel may be out of specification. Refer to Wheel Runout above.
3. If the new high spot is NOT within 102 mm (4.0 inch) of either high spot, draw an arrow on the tread from new high spot toward the original (2). Break down the tire and remount it 90 degrees on rim in that direction, then re-measure runout. This will normally reduce the runout to an acceptable amount.
Once back together, road test the vehicle for at least 5 miles, following the format described in Road Test. If vibration persists, and all components tested are within specification, the tires may have an excessive radial force condition. Radial force variation can be checked using a wheel balancer capable of measuring radial force variation, such as the Hunter GSP 9700 Vibration Control System (Wheel Balancer) or equivalent. If this equipment is not available, consult with the tire manufacturer.