Just had my 2011 XC70 in to the dealer to go through things at 112,000 miles and diagnose a front end noise that i suspected to be a wheel bearing. (I'm a motorcycle mechanic)
Long story short, they proposed I change the hub along with the axle for $2300. I've already done this myself for under $500, but there's a bunch more I've yet to do.

They also found worn out rear trailing arm bushings, leaking brake vacuum pump and stated "Found One Way Pulley Seized" which is where my question comes in...
Which Pulley is it? There's an alternator pulley, a drive belt and a tensioner pulley...or do I just change them all?

I'd like to order up the parts along with the water pump and belt and knock out the Brake Vacuum pump seal while I have everything apart.

Any advise appreciated!