Important: The following steps must be completed before using the analysis tables
  or the symptom tables.
- Perform the 
Vibration Analysis - Road Testing 
 table before using the other Vibration Analysis tables
  or the Symptom tables in order to effectively diagnose the customer's concern.
 
The use of Vibration Analysis - Road Testing will first provide
 duplication  of virtually any vibration concern and then identify the correct
 procedure       for diagnosing the area of concern which has been duplicated.
- Review the following Vibration Diagnostic Process.
 
- Review the general descriptions to familiarize yourself with vibration
  theory and terminology. Reviewing this information will help you determine
 whether the condition   described by the   customer is a potential operating
 characteristic or not. Refer to 
Vibration Theory and Terminology 
.
 
Vibration Diagnostic Process
Important: Using the following steps of the vibration diagnostic process will help
  you to effectively narrow-down and pin-point the search for the specific
 source       of a vibration concern and to arrive at an accurate repair.
- Gather specific information on the customer's vibration concern.
 
- Perform the road testing steps in sequence as identified in Vibration
  Analysis - Road Testing in order to duplicate the customer's concern and
 evaluate   the symptoms of the concern under changing conditions. Observe
 what the vibration   feels like and what it sounds like. Observe when the
 symptoms first appear,   when they change, and when they cease.
 
- Determine if the customer's vibration concern is truly an abnormal
  condition or something that is potentially an operating characteristic of
    the vehicle.
 
- Systematically eliminate or "rule-out" possible vehicle
  systems.
 
- Focus diagnostic efforts on the remaining vehicle system and systematically
  eliminate or "rule-out" possible components of that system.
 
- Make a repair on the remaining component, or components, which
  have not been eliminated systematically, and must therefore be the cause
 of   the vibration.
 
- Verify that the customer's concern has been eliminated or at least
  brought to an acceptable level.
 
- Again perform the road testing steps in sequence as identified
  in Vibration Analysis - Road Testing in order to verify that the vehicle
 did       not have more than one vibration occurring.
 
Preliminary Visual/Physical Inspection
|     •  | Inspect for aftermarket equipment and modifications which could
  affect the operation of the vehicle rotating component systems. | 
 
|     •  | Inspect the easily accessible or visible components of the vehicle
  rotating component systems for obvious damage or conditions which could
cause     the symptom. | 
 
|     •  | Inspect the tire inflation pressures for the proper pressure. | 
 
Diagnostic Aids
Improper component routing or isolation, or components which are worn
  or faulty may be the cause of intermittent conditions that are difficult
 to    duplicate. If the vibration concern could not be duplicated by following
      the  steps of the Vibration Diagnostic Process, refer to 
Vibration Diagnostic Aids 
.