Do harmonic balancers squeal when they are bad?

Answer 1

Yes they can squeal when the rubber to metal bond has been broken, the metal ring then moves over the rubber making a loud squeal. If that is the case it can sound much like a pending bearing failure on the alternator or water pump. This also means that your balancer can potentially fly apart at any moment and cause severe damage to the radiator or crankshaft sensor (if equipped). Also when the metal belt pulley does eventually slip off it will no longer be driving all the pulleys.