My emergency brake is useless. I have it adjusted all the way as tight as it will go. My back brake is like new and works great. Ifigure it needs a new cable but which one the front one or the rear or both. Is this what usually needs to be done or is there another fix. I figure after watching my truck roll down my shop driveway, peeling my door off, slamming two boats, its time to get it working. thanks for any help.