This section describes the techniques and procedures for
correcting the following types of vibrations:
• | Engine firing frequency |
Identifying the Concern
Important: Do NOT attempt to repair a normal condition, or the customer will probably
be convinced that the vehicle has a problem. Customer satisfaction becomes
extremely difficult after this point.
The first step in diagnosing a vibration concern is to identify the
exact vibration that concerns the customer.
It is a good idea to ride with the customer, making the comparison with
the customer present and explain the situation.
Sometimes the vibration can be duplicated at a given speed. Other vibrations
may not be as evident and may require further troubleshooting by performing
a road test with the customer in the vehicle in order to determine the specific
vibration complaint.
Ask the following questions when attempting to identify a vibration
complaint:
• | At what speed is the vibration the worst? |
• | Can the vibration be felt? If so, where? |
• | Can the vibration be heard? If so, what does the noise sound like? |
• | Does the engine or the vehicle load affect the vibration? |
• | Does the vibration occur in more than one gear range? |
• | When did the vibration first appear? |
The answers to these questions will help in duplicating and diagnosing
the vibration.
If you suspect that the vibration is normal, compare the vibration with
a vehicle that is equipped in the same way, including the following factors:
• | Engine driven accessories |
• | Suspension performance type |
A Process of Elimination
You must understand a few basic concepts before attempting to diagnose
a vibration. As in any diagnostic process, you must perform the following
steps:
• | Decipher the information |
• | Make your correction based on the results |
Road test the vehicle and inspect the vehicle in a manner which systematically
eliminates different components. This process supplements the information
which you have received from the customer concerning the complaint. Concentrating
efforts on the areas that have not been eliminated will make repairs faster
and more effective.