Loud squeel when wheel turned all the way
 

I had my car in the dealer for a loud squeel when the wheel is turned all the way to the left or right. I know that they normally make a hissing noise, but this is a full out squeel. Dealer "Could not replicate" Any ideas? :dunno:

If the steering is at physical end of movement and you hold pressure on the steering wheel the power steering pump is still trying to push more fluid through, and can't... So the pump gets harder to turn. You are likely hearing the belt slipping on the power steering pump pulley.

If the belt and/or tensioner is old and worn out, replacing it will most likely knock the noise right out... but is more of a user error in general. It isn't really good for the pump or steering hydraulic system to do this. Easiest fix, don't hold pressure on the steering wheel when turned all the way. (if that is actually the case at least)