4 inch lift on a 79 f-150

I bought a 4 inch lift for a 79 f-150, ad I've been told with a 4" lift I need to replace my pitman arm. is this true? and is there any other parts I need to replace for the lift to fit properly?

You need pitman arm and shocks..

And a drop bracket for the track bar to do along with that drop pitman arm or you will end up with horrible bump steer from not having the track bar and drag link parallel.