| Table 1: | Vibration Symptoms that are Felt |
| Table 2: | Vibration Symptoms that are Heard |
- Begin the diagnosis of vibration concern by reviewing Diagnostic Starting Point - Vibration Diagnosis and Correction to be familiar with the correct diagnostic procedures.
- Perform the Vibration Analysis - Road Testing before using these symptom tables to duplicate and effectively diagnose the customer's concern.
Important: Perform the following steps in sequence BEFORE using these symptom tables.
Symptom Tables
Refer to a Vibration Analysis table as indicated in the following symptom tables, based on the most dominant characteristics of the customer's vibration concern, felt or heard, under the appropriate occurrence condition.
Type | Description | Typical Frequency Range | Condition of Occurrence | Area of Focus |
|---|---|---|---|---|
Shake | Can sometimes be seen or felt in the steering wheel, seat or console. Relative Terms: shimmy, wobble, waddle, shudder, hop | 5-20 Hz | Vehicle Speed Sensitive Still occurs during coast down in NEUTRAL | |
Vehicle Speed Sensitive Affected by torque/load/or steering input | ||||
Engine Speed Sensitive | ||||
Roughness | Similar to the feeling of holding a jigsaw | 20-50 Hz | Vehicle Speed Sensitive Still occurs during coast down in NEUTRAL | |
Engine Speed Sensitive | ||||
Vehicle Speed Sensitive Affected by torque/load/or steering input | ||||
Buzz | Similar to the feeling of holding an electric razor May be felt through handing the steering wheel, stepping on the vehicle floor, or sitting on the seat. | 50-100 Hz | Vehicle Speed Sensitive Affected by torque/load/or steering input | |
Engine Speed Sensitive | ||||
Tingling | May produce a "pins and needles" sensation or may put hands or feet "to sleep" Highest vibration frequency range can still be felt. | Greater than 100 Hz | Vehicle Speed Sensitive Affected by torque/load/or steering input | |
Engine Speed Sensitive |
Type | Description | Typical Frequency Range | Condition of Occurrence | Area of Focus | ||||
|---|---|---|---|---|---|---|---|---|
Boom | The interior noise usually heard similar to the noise of a bowling ball rolling down an alley, deep thunder, or a bass drum
| 20-60 Hz | Vehicle Speed Sensitive Still occurs during coast down in NEUTRAL | |||||
Vehicle Speed Sensitive Affected by torque/load/or steering input | ||||||||
Moan or Droan | Similar to the sound of a bumblebee or blowing air across the top of a bottle
| 60-120 Hz | Vehicle Speed Sensitive Affected by torque/load/or steering input | |||||
Engine Speed Sensitive | ||||||||
Howl | Similar to the sound of the wind howling | 120-300 Hz | Vehicle Speed Sensitive Affected by torque/load/or steering input | |||||
Engine Speed Sensitive | ||||||||
Whine | Similar to the sound of mosquitoes, turbine engines, or vacuum cleaners | 300-500 Hz | Vehicle Speed Sensitive Affected by torque/load |
