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Symptoms - Vibration Diagnosis and Correction

Symptoms - Vibration Diagnosis and Correction


Note

Perform the following steps in sequence BEFORE using these symptom tables.



1. Begin the diagnosis of a vibration concern by reviewing Diagnostic Starting Point - Vehicle to become familiar with the diagnostic process used to properly diagnose vibration concerns.

2. Perform the Vibration Analysis - Road Testing table before using these symptom tables in order to duplicate and effectively diagnose the customer's concern.


Symptom Tables

Refer to a Vibration Analysis table as indicated in the following symptom tables, based on the most dominant characteristic of the customer's vibration concern, felt or heard, that is evident during the appropriate condition of the occurrence.

Vibration Symptoms that are Felt

Category Description Typical Frequency Range Condition of Occurrence Area of Focus
Shake Can sometimes be seen or felt in the steering wheel, seat or console. Related terminology: shimmy, wobble, waddle, shudder, hop 5-20 Hz Vehicle Speed Sensitive Still occurs during coast down in NEUTRAL Go to Vibration Analysis - Tire and Wheel
Vehicle Speed Sensitive Affected by torque/load Go to Vibration Analysis - Driveline
Vehicle Speed Sensitive Affected by steering input Go to Vibration Analysis - Hub and/or Axle Input
Engine Speed Sensitive Go to Vibration Analysis - Engine
Roughness Similar to the feeling of holding a jigsaw. 20-50 Hz Vehicle Speed Sensitive Still occurs during coast down in NEUTRAL Go to Vibration Analysis - Tire and Wheel
Vehicle Speed Sensitive Affected by torque/load Go to Vibration Analysis - Driveline
Vehicle Speed Sensitive Affected by steering input Go to Vibration Analysis - Hub and/or Axle Input
Engine Speed Sensitive Go to Vibration Analysis - Engine
Buzz Similar to the feeling of holding an electric razor. May be felt in the hands through the steering wheel, in the feet through the floor, or in the seat of the pants. 50-100 Hz Vehicle Speed Sensitive Affected by torque/load Go to Vibration Analysis - Driveline
Vehicle Speed Sensitive Affected by steering input Go to Vibration Analysis - Hub and/or Axle Input
Engine Speed Sensitive Go to Vibration Analysis - Engine
Tingling May produce a "pins and needles" sensation or may put hands or feet "to sleep". Highest vibration frequency range that can still be felt. Greater than 100 Hz Vehicle Speed Sensitive Affected by torque/load Go to Vibration Analysis - Driveline
Vehicle Speed Sensitive Affected by steering input Go to Vibration Analysis - Hub and/or Axle Input
Engine Speed Sensitive Go to Vibration Analysis - Engine


Vibration Symptoms that are Heard

Category Description Typical Frequency Range Condition of Occurrence Area of Focus
Boom Usually heard as an interior noise similar to the noise of a bowling ball rolling down an alley, deep thunder, or a bass drum.
Related terminology - droning, growling, moaning, roaring, rumbling, humming

May not be accompanied by a perceptible vibration (roughness)


20-60 Hz Vehicle Speed Sensitive Still occurs during coast down in NEUTRAL Go to Vibration Analysis - Tire and Wheel
Vehicle Speed Sensitive Affected by torque/load Go to Vibration Analysis - Driveline
Vehicle Speed Sensitive Affected by steering input Go to Vibration Analysis - Hub and/or Axle Input
Moan or Drone Similar to the sound of a bumblebee or blowing air across the top of a bottle.
Related terminology - humming, buzzing, resonance

May be accompanied by a perceptible vibration (buzz)


60-120 Hz Vehicle Speed Sensitive Affected by torque/load Go to Vibration Analysis - Driveline
Vehicle Speed Sensitive Affected by steering input Go to Vibration Analysis - Hub and/or Axle Input
Engine Speed Sensitive Go to Vibration Analysis - Engine
Howl Similar to the sound of the wind howling. 120-300 Hz Vehicle Speed Sensitive Affected by torque/load Go to Vibration Analysis - Driveline
Vehicle Speed Sensitive Affected by steering input Go to Vibration Analysis - Hub and/or Axle Input
Engine Speed Sensitive Go to Vibration Analysis - Engine
Whine Similar to the sound of mosquitoes, turbine engines, or vacuum cleaners. 300-500 Hz Vehicle Speed Sensitive Affected by torque/load - 2WD mode Go to Transmission diagnostic information
Vehicle Speed Sensitive Affected by torque/load - 4WD mode Go to Transfer Case diagnosis information