Can failed hydroboost lock up the rear drums?

[NapaBavarian]

Friend of mine had this trouble on an '84 chevy 1 ton cab n chassis, rear drums are locked up, looks like a brake problem to me, inside the drums, but what do I know?

 

[towcat]

you would see your brake pedal drop down when you fire up the engine.
otherwise, the hydro would not be working.

 

[NapaBavarian]

Thanks, that seems logical, I felt it sounded like an issue within the drums.