Sierra 1500 4WD V8-5.3L VIN B (2005)
The number(s) below refer to the step(s) in the diagnostic table.
3. This test is to verify that the whine is being caused by the accessory drive component(s). Remove the drive belt(s) and operate the engine for a few
seconds, this will verify if the whining noise is related to the accessory drive component. With the drive belt(s) removed the water pump will not
operate and the engine may overheat. Also Diagnostic Trouble Codes (DTCs) may set when the engine is operated with the drive belt(s) removed.
4. This inspection should include checking the drive belt tensioner and the drive belt idler pulley bearings. The drive belt(s) may have to be installed
and the accessory drive components operated separately by varying their loads.
