steering vacuum leak?

[deeds98f150]

Question when i turn my wheel i can hear a sort of hiss i guess i didnt think the steering was vacuum controled am i wrong? What could cause this and is it something that i have to fix?

[codwel09]

When does it do it? When you turn it all the way to the right and left? Could just be the steering bleed off hissing when its all the way.

[sutton17]

When u turn all the ways left/right the hydraulic pressure will go over relief causing a hissing sound, hope that helps

[fordfreek94]

Mine sounds like tht no matter how far I turn it..is tht normal its an 01