Could be a bad belt, bad pulley (bearing), misaligned pulley, low belt tension causing the belt to slip on pulleys.
Here's a little trick:
Spray the belt lightly with a spray bottle. If the noise level stops or decreases for a few seconds, then returns louder, a misalignment problem is likely. If the noise immediately increases after the belt is sprayed, slipping is likely.
If you determine the belt is slipping, check your tensioner.
Friday, May 7th, 2010 AT 11:52 AM