Sierra 3500 4WD V8-6.6L DSL Turbo VIN 2 (2004)
Drive Belt Excessive Wear Diagnosis
Diagnostic Aids
Excessive wear on a drive belt is usually caused by incorrect installation or the incorrect drive belt for the application.
Minor misalignment of the accessory drive belt pulleys will not cause excessive wear, but will probably cause the drive belt to make a noise or fall off.
Excessive misalignment of the accessory drive belt pulleys will cause excessive wear and may also make the drive belt fall off.
Test Description
Steps 1 - 6
The numbers below refer to the steps in the diagnostic table.
2. This inspection is to verify the drive belt is correctly installed on all of the accessory drive pulleys. Wear on the drive belt may be caused by
mis-positioning the drive belt by one groove on a pulleys.
3. The installation of a drive belt that is too wide or too narrow will cause wear on the drive belt. The drive belt ribs should match all of the grooves
on the pulleys.
4. This inspection is to verify the drive belt is not contacting any part of the engine or body while the engine is operating. There should be sufficient
clearance when the accessory drive components load varies. The drive belt should not come in contact with an engine or a body component when
snapping the throttle.
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
