I am hearing a squalling belt noise (belts are 2 months old) and my mechanic pointed to this pulley (in the picture) as the cause of the noise. It looks like the rubber seal inside the pulley is falling apart and it causes the pulley to vibrate. He said it's the main engine pulley. I called my local Lexus parts guy and he does not know what pulley I'm referring to. Is this the crankshaft pulley?
I found this picture of an RX330 engine and the large pulley at the bottom is what I am referring to.
Please help.

 

Hopefully this will help:
http://www.partswebsite.com/oemlexus...75&catid=30147

 

Thank you. This is the crank pulley (or Harmonic Balancer). It's ridicules that a pulley costs $260...

 

This is exactly why it's so expensive. It's not just a pulley, it is a balancer. It has something to do with reducing vibrations, or something like that.