Drive Belt Rumbling

Diagnostic Aids
Vibration when the engine is operating may cause a body component or another part of the vehicle to produce a rumbling noise.
The drive belt(s) may have a condition that can not be seen or felt. Sometimes replacing the drive belt(s) may be the only repair for the symptom.
If after replacing the drive belt(s) and completing the diagnostic table the noise is only heard with the drive belt(s) installed, there may be an accessory drive component failure. Varying the load on the accessory drive components may aid in identifying which accessory drive component is causing the rumbling noise.

Test Description
The number(s) below refer to the step number(s) on the diagnostic table.
2. This test is to verify that the symptom is present during diagnosing. Other vehicle components may cause a similar symptom.
3. This test is to verify that the drive belt(s) is causing the rumbling noise. The rumbling noise may be confused with an internal engine noise due to the similarity in the description. Remove only one drive belt at a time if the vehicle has multiple drive belts. With the drive belt(s) removed the water pump may not operate and the engine may overheat. Also DTCs may set when the engine is operating with the drive belt(s) removed.
4. Inspect the drive belt(s) to ensure that the drive belt is not the cause of the noise. Small cracks across the ribs of the drive belt will not cause the rumbling noise. Belt separation is identified by the plys of the drive belt separating, this may be seen at the edge of the belt or felt as a lump in the belt.
5. Small amounts of pilling is a normal condition and acceptable. When the pilling is severe the drive belt does not have a smooth surface for proper operation.