Squealing from front end when turning to the right. on 2008 Nissan Xterra

When I turn the steering wheel to the right or break, my car is squealing, like metal on metal and it feels like something is rubbing. The mechanic i just brought it to is saying it's my a/c compressor deteriorating internally and my serpentine belt is cracked. My a/c works, it does NOT squeal when i turn it on, I thought for sure he would tell me it was breaks, rotors or something with the steering or axle. Is the mechanic lying to me? What could this be?

2 answers
That doesn't sound right to me, but I'm not checking it. I would consider the brake wear squealers.
I would bring it to another mechanic and have it diagnosed(WARNING-That may cost a few dollars)........It may end up worth it.