I just picked up a single axle trailer last week that the wiring harness is messed up on. In the process of rewiring it the brakes on the axles need checked/replaced. currently the wires are cut to them, so I assume they are shot. I pulled one brake drum off and they are shoe type brakes. What happens is there is an electromagnet that is pulled to the face of the drum that the wheel mounts to. When this happens it drags and pulls the lever that engages the brakes. This setup apparently doesn't work in reverse . What do I ask for when looking for parts? Does this type of brake setup have a name? I probably don't need brakes, but I would feel better with them. The trailer axle is either a 3000 or 4000 lb axle with a 6 bolt hub.