I'm finding out a leaking manifold related to the turbo can sound just like a bearing squeel? I was blaming the serpentine belt and/or the alternator for what sounds like a belt squeel. How do I properly diagnose where this squeel is coming from if it's possible it's coming from something related to the turbo? I had my lower alternator go out right when this started so I was automatically assuming it was the alternator. Now that I have a new alternator and the squeel still exists I need to figure out what's causing it. It definitely goes in time with engine revs. I was assuming when it quieted down it was just the bearing warming up, but it could indeed be coinciding with turbo spin/pressure. I just want to make sure it's really that and I don't know how to verify it.

 

Have someone listen under each front fender, power brake load it in gear to build boost. It is very common to break the manifold studs near the rear exhaust ports on both sides. If you have more than one on each side it is easier to pull the engine to repair. The manifolds warp and we replaced them on our work trucks when this occured. We had 10 6.4 powered F550s at one time. We ran them for 200,000 miles, we still have one early 08 low mile one.