steering noise

[02 f250]

My truck just started doing this it seems to only happen when the fluid is hot but when you turn the wheel you can feel a slight resistance only in a couple spots but it makes a whinning sound that sounds like its coming from under the steering wheel can here nothin from the outside of the truck is really weird only does it once an a while has anyone had anything like this ?

[JEL]

Mine started doing this a couple of weeks before I had the high pressure hose in the PS pump rupture, lost power steering and brakes in a matter of seconds. I wasn't losing any fluid so to speak, but there was probably a tiny pinhole in the hose that eventually led to a rupture, I just didn't know becuase the fluid level was always right at the top; I think it was just pulling a little air causing the whine.