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Vibration Analysis - Tire and Wheel

Vibration Analysis - Tire and Wheel

Test Description

The numbers below refer to the step numbers in the diagnostic table:

4

A build-up of foreign material on a tire and wheel assembly and/or a damaged, abnormally or excessively worn tire and wheel assembly could cause a vibration disturbance.

6

Tire and wheel assemblies that exhibit excessive runout when measured while mounted on the vehicle, may or may not be contributing to, or causing a vibration disturbance. On-vehicle runout, if present, could contribute to, or cause a vibration disturbance, but the cause of the on-vehicle runout may not be the tire and wheel assemblies.

7

Tire and wheel assemblies that exhibit excessive runout when measured off of the vehicle could cause a vibration disturbance.

9

Tire and wheel assemblies that exhibit marginal runout-within acceptable limits, but close to the maximum-when measured off of the vehicle could still be contributing to a vibration disturbance, if its mating hub/axle flange also exhibits marginal runout. When the tire and wheel assembly and the hub axle flange are mounted to each other, the combined stack-up of their marginal amounts of runout could combine to produce an excessive amount of runout, which could cause a vibration disturbance.

14

Brake rotors and/or brake drums, if equipped, that exhibit excessive imbalance could contribute to, or possibly cause a vibration disturbance.

15

A hub/axle flange and/or wheel studs that exhibit excessive runout could cause a vibration disturbance.

16

When the tire and wheel assembly and the hub axle flange are mounted to each other, the combined stack-up of their marginal amounts of runout could combine to produce an excessive amount of runout, which could cause a vibration disturbance. Match-mounting or vectoring the tire and wheel assembly to the hub/axle flange will modify the amount of combined runout.

18

Force variation may be present in a tire and wheel assembly that exhibited acceptable balance and runout. Force variation, if present, could contribute to, or cause a vibration disturbance.

20

Vibration disturbances could be affected by, or possibly caused by, components that are susceptible to steering input and/or torque-load input.

22

On-vehicle balancing, or finish-balancing can be used to reduce small amounts of imbalance which may be present as a result of the combined stack-up of the tire and wheel assembly with other components which may exhibit marginal balance.


Step Action Yes No
1
Has the Vibration Analysis - Road Testing table been completed? Go to Step 2 Go to Vibration Analysis - Road Testing
2
Based on the Vibration Analysis - Road Testing table, is the concern first-order tire and wheel assembly related? Go to Step 4 Go to Step 3
3
Based on the Vibration Analysis - Road Testing table, is the concern second-order, or higher-order tire and wheel assembly related? Go to Step 18 Go to Vibration Analysis - Road Testing
4
Visually inspect the tire and wheel assemblies for the following:
• Debris build-up, such as packed mud, undercoating, ice/snow buildup, road tar, etc.

• Damage, abnormal or excessive wear


Refer to Tire and Wheel Inspection . Do any of the tire and wheel assemblies exhibit any of the conditions listed? 		Go to Step 5 Go to Step 6
5

1. Remove the debris from the tire and wheel assemblies.

2. Replace the damaged, abnormally or excessively worn wheels or tires as necessary.


Did you complete the repair or replacement? 		Go to Step 23 -
6
Measure the on-vehicle runout of the tire and wheel assemblies. Refer to Tire and Wheel Assembly Runout Measurement - On-Vehicle . Does the runout measurement indicate a runout concern? Go to Step 7 Go to Step 12
7
Measure the off-vehicle runout of the tire and wheel assemblies. Refer to Tire and Wheel Assembly Runout Measurement - Off Vehicle . Does the runout measurement indicate a runout concern? Go to Step 19 Go to Step 8
8
Is the vehicle equipped with run-flat tires? Go to Step 12 Go to Step 9
9
Are any of the tire and wheel assembly runout measurements marginal; within acceptable limits, but close to the maximum? Go to Step 10 Go to Step 15
10
Note

Ensure that each tire and wheel assembly that is match-mounted is properly balanced before reinstalling to the vehicle.



1. Match-mount the tire-to-wheel for each tire and wheel assembly with marginal runout. Refer to Tire-to-Wheel Match-Mounting (Vectoring) .

2. Measure the runout of each match-mounted tire and wheel assembly. Refer to Tire and Wheel Assembly Runout Measurement - Off Vehicle .


Were you able to significantly reduce the amount of tire and wheel assembly runout? 		Go to Step 11 Go to Step 19
11
Re-measure the on-vehicle runout of the tire and wheel assemblies. Refer to Tire and Wheel Assembly Runout Measurement - On-Vehicle . Does the runout measurement indicate a runout concern? Go to Step 15 Go to Step 23
12
Inspect the balance of the tire and wheel assemblies. Refer to Tire and Wheel Assembly Balancing - Off Vehicle . Are any or the tire and wheel assemblies out of balance? Go to Step 13 Go to Step 14
13
Balance the tire and wheel assemblies as necessary. Refer to Tire and Wheel Assembly Balancing - Off Vehicle . Were you able to achieve balance? Go to Step 23 Go to Vibration Diagnostic Aids
14

1. Inspect the brake rotors and brake drums, if equipped, for damage.

2. Inspect the balance of the brake rotors and brake drums, if equipped. Refer to Brake Rotor/Drum Balance Inspection .

3. Replace brake rotors and/or brake drums, if equipped, that are damaged and/or out of balance.


Did you find and correct a condition? 		Go to Step 23 Go to Step 17
15

1. Measure the runout of the hub/axle flanges and the wheel studs, if equipped.

2. Inspect the wheel bolts, if equipped, for straightness and damage.

3. Refer to Hub/Axle Flange and Wheel Stud Runout Inspection .

4. If the inspection procedure indicates a runout concern, replace the appropriate components:

• Wheel studs, if equipped

• Wheel bolts, if equipped

• Wheel bearing/hub assembly


Did you find and correct a condition? 		Go to Step 23 Go to Step 16
16

1. Match-mount the tire and wheel assemblies to hub/axle flange. See Tire and wheel assembly to hub/axle flange, match-mounting .

2. Re-measure the on-vehicle runout of the tire and wheel assemblies. Refer to Tire and Wheel Assembly Runout Measurement - On-Vehicle .


Were you able to significantly reduce the amount of on-vehicle tire and wheel assembly runout? 		Go to Step 23 Go to Step 2
17
Inspect for radial and lateral force variation. Refer to Tire and Wheel Assembly Isolation Test . Were you able to isolate one or more of the tire and wheel assemblies as the cause of the disturbance? Go to Step 19 Go to Step 20
18
Inspect for radial and lateral force variation. Refer to Tire and Wheel Assembly Isolation Test . Were you able to isolate one or more of the tire and wheel assemblies as the cause of the disturbance? Go to Step 19 Go to Step 21
19
Replace any tires and/or wheels that were isolated as the cause of the disturbance, as necessary. Did you complete the replacement? Go to Step 23 -
20
Perform the Vibration Analysis - Hub/Axle Input table. Refer to Vibration Analysis - Hub and/or Axle Input . Did you find and correct a condition? Go to Step 23 Go to Step 22
21
Perform the Vibration Analysis - Hub/Axle Input table. Refer to Vibration Analysis - Hub and/or Axle Input . Did you find and correct a condition? Go to Step 23 Go to Vibration Diagnostic Aids
22
Finish-balance the tire and wheel assemblies on the vehicle. See Tire and wheel assembly balancing- on vehicle . Did you complete the on-vehicle finish balancing? Go to Step 23 -
23

1. Install or connect components that were removed or disconnected during diagnosis.

2. Perform the Vibration Analysis - Road Testing table. Refer to Vibration Analysis - Road Testing .


Is the vibration still present? 		Go to Step 2 System OK