C 2500 Truck 2WD V8-5.7L VIN R (1997)
Drive Belt: Testing and Inspection
DRIVE BELT DIAGNOSIS
Drive belts and pulleys wear evenly with use. Unusual signs of wear indicate some correction is needed. This diagnostic chart will aid in diagnosing
multiple ribbed belt system problems.
Definitions:
Chirping: A high pitched noise that is usually heard once per revolution of a pulley or belt. It is also usually heard, at idle and is most common on
cold damp mornings. By squirting water onto a chirping belt, the noise will momentarily go away.
Squeal: A loud screeching noise that is usually caused by a slipping belt. The noise usually occurs when a heavy load is applied to the belt, such
as compressor engagement, accelerating the seized pulley.
Whine: A high pitched continuous noise that may be caused by a failed bearing.
Faint Cyclic Rumbling: A deep low frequency noise (once per revolution of the belt).
Pilling: The random accumulation of rubber dust in the bottom of the multi-ribbed belt grooves. A small amount pilling is normal. Operation of
the drive belt system will not be affected unless buildup exceeds 1/3 of the belt groove depth.
