Squeals when turning at low speed

[InLimbo]

Hi, I just bought an '86 F350 w/ a '92 7.3 engine. So far, only at low speed (i.e. parking/driveway speed), it squeals at certain points in a turn. Guy I bought it from said it needed power steering fluid. I checked what I believed to be the PS fluid. It was full. I'm not sure if he meant fill it up because it's low, or replace it.

Any ideas?

Thanks!!

[1990F2507.3]

The older power steering pumps always sqwauk or squeal when you turn it all the way one side or the other. One thing you can do to quiet it down but it wont go away is flush the system and add some lucas to it... but it will still have a slight sqwauk to it.