Sierra 3500 4WD V8-6.6L DSL Turbo VIN 2 (2004)
Drive Belt: Testing and Inspection
Drive Belt Falls Off
Drive Belt Falls Off Diagnosis
Diagnostic Aids
If the drive belt repeatedly falls off the accessory drive belt pulleys, this may be caused by a pulley misalignment.
An extra load that is quickly applied or released by an accessory drive component may cause the drive belt to fall off. Verify that the accessory drive
components are operating properly.
If the drive belt is the incorrect length, the drive belt tensioner may not maintain the proper tension on the drive belt.
Test Description
Step 1 - 2