Silverado 3500 2WD V8-6.6L DSL Turbo VIN 2 (2004)
The numbers below refer to the steps 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 is causing the rumbling. Rumbling may be confused with an internal engine noise due to the similarity in the
description. Operate the engine for a few seconds, this will verify if the rumbling noise is related to the drive belt or not. With the drive belt
removed the cooling fan will not operate and the engine may overheat. Also Diagnostic Trouble Codes (DTCs) may set when the engine is
operated with the drive belt removed.
4. Inspect the drive belt 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
noise. Belt separation is identified by the plys of the 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.
