I know this should really be in the nuts and bolts, but I will start one there if there is any interest. I have just sorted my parking brake, which is a quite simple foot brake and cable to a propshaft drum. But now I have just helped a mate with the one that auto goes into brake on when you put it into park, or turn off the ignition. Apparently these are common on RVs after about 1994, and can be both a big problem not being able to move, and costly for replacement parts. Some who have them may be acquainted with the little green switch, and also the little grey one. If fluid is lost thru a dodgy switch, the brakes come on and stay on, and often badly adjusted ones allow you to still drive, but wear out the brake shoes in a few miles. If the dash light stays on, its telling you that the parking brake has remained on. Any one want more info just ask, and I will try and help.