How to Install Electrical Brakes on a Horse Trailer

Older horse trailers may not have come equipped with brakes or may need an upgrade from hydraulic surge brakes that no longer work properly. As most states now require working brakes on trailers over a GTW as low as 1500 pounds, adding or replacing these brakes has become important. Fortunately this is a task that can be accomplished with a few simple tools.

Things You'll Need

• Electric brake kit
• Mounting bolts
• Socket set
• 12-gauge automotive wire
• Solderless butt connectors
• Solderless ring connectors
• Solderless crimping tool
• Self tapping screws
• Electric drill with a socket to drive the self tapping screws

Instructions

1. Jack up the trailer and, after supporting it on jack stands, remove the wheels and hubs.

2. Wire brush the brake mounting flanges to remove any rust. This is the square flange near the end of the axle.

3. Install an electric brake assembly on each flange using brake flange mounting bolts. Tighten securely. The brake is installed with the actuating arm in a vertical position with the magnet at the bottom.

4. Crimp a solderless ring terminal on one of the two wires from the brake assembly. Attach to the trailer frame with a self tapping screw. Allow enough slack for the full movement of the trailer suspension.

5. Connect the second wire of each brake using a 12-gauge wire. Splice another 12-gauge wire to this wire and run this wire along the trailer frame to the trailer connector.

6. Pack the bearings in the new hub/brake drum assembly with high quality wheel bearing grease and install the hubs on the axle. Adjust the wheel bearings and install a new cotter pin to lock in place. Replace the dust covers.

7. Install the wheel and tire assemblies on the drums. Lower the trailer to the ground after removing the jack stands.

8. Replace the trailer connector with a 5- or 6-terminal connector if necessary to connect the brake wiring to the tow vehicle, which must be equipped with an electric brake controller.