Ford: brake problems, wheel cylinders, brake shoes

Question
I have been hearing a dragging /rubbing noise since replacing my rear brake shoes, and some times they want to grab. i had the drums turned, I went to the Ford dealer twice had the wheel cylinders changed. I changed the power booster and master cylinder. The problem just don't go away. Any clues to what I should do next??  

Answer
Martin, you might want to look at your brake adjuster inside the drum.  It is possible that you have the shoes adjusted to tight.  I am assuming that your pedal is not hitting the floor.  If it is, then I would bleed the brakes again until you get a smooth and tight pedal.  The only other thing that comes to mind is that you may need to flush the brake lines.  As brake fluid gets older, it begins to sludge and will cause the brakes to stick.  I hope this helps,   Jason