Silverado 2500 4WD V8-6.6L DSL Turbo VIN 2 (2004)
Steps 1 - 5
Steps 5 (continued) - 9
The number(s) below refer to the steps in the diagnostic table.
2. The squeal may not be engine related. This step is to verify that the engine is making the noise. If the engine is not making the noise, do not
proceed further with this table
3. The squeal may be an internal engine noise. Remove the drive belt and operate the engine for a few seconds, this will verify if the squealing noise
is related to the drive belt or an accessory drive component. With the drive belt removed the cooling fan will not be operate and the engine may
overheat. Also Diagnostic Trouble Codes (DTCs) may set when the engine is operated with the drive belt removed.
4. This test is to verify that an accessory drive components does not have a seized bearing. With the belt removed, test the bearings in the accessory
drive components for smooth operation. Also test the accessory drive components with the engine operating by varying the load on the accessory
drive components to verify that the components is operating properly.
5. This test is to verify that the drive belt tensioner is operating properly. If the drive belt tensioner is not operating properly, proper belt tension may
not be achieved to keep the drive belt from slipping which could cause a squealing noise.
6. This test is to verify that the drive belt is not too long, which would prevent the drive belt tensioner from operating properly. Also if the incorrect
