Envoy 4WD V8-5.3L VIN M (2005)
5. Inspection of the accessory drive pulleys should include inspecting for bends, dents, or other damage that would prevent the drive belt from seating
properly in the pulley grooves or on the smooth surface of a pulley when the back side of the drive belts is used to drive the pulley.
6. Accessory drive component brackets that are bent or cracked will also cause the drive belts to fall off.
7. Inspection of the fasteners can eliminate the possibility that a incorrect bolt, nut, spacer, or washer was installed. Missing, loose, or incorrect
fasteners may cause pulley misalignment from the accessory drive brackets moving under load. Over tightening the fasteners may cause
misalignment of the accessory component brackets.
Drive Belt Rumbling
Drive Belt Rumbling Diagnosis
Diagnostic Aids
Vibration from the engine operating may cause a body component or another part of the vehicle to make rumbling noise.
The drive belts may have a condition that can not be seen or felt. Sometimes replacing the drive belts may be the only repair for the symptom.
If after replacing the drive belts and completing the diagnostic table, the rumbling is only heard with the drive belts installed, there might be an
accessory drive component failure. Varying the load on the accessory drive components may aid in identifying which component is causing the
rumbling noise.
Test Description
The numbers below refer to the steps in the diagnostic table.
