Trailer Brakes

Most recreational trailers use electric brakes; exceptions can include rental car-hauling trailers, which use surge brakes, and some large fifth wheels, which use air brakes. Most require the user to adjust the brake gain (braking intensity) to compensate for varying trailer loads.

Exceptions can include:

  1. Surge brakes on trailers for hauling rental cars.
  2. Air brakes on some large fifth wheels.


Electric brakes require a brake controller in the cabin of the tow vehicle. Electric brakes use electromagnets to actuate the drum brakes. You control the electricity to the brakes through the brake controller and the brake light circuit on your vehicle.



The brake controller is typically installed in the vehicle's driving compartment by running an electrical line from the trailer to the trailer wiring connector. Most require the user to adjust brake gain (braking intesnsity) to compensate for varying trailer load.

If your vehicle came from the factory with a Class III or better towing hitch installed, chances are that it has a quick plug under the dash for a brake controller. A "pigtail" connector might also have been included in the glove box.



A breakaway system is a small battery on your trailer with a switch connected to a strong cable. You attach the cable to your vehicle's trailer hitch. If your trailer comes loose and your safety chains fail, the trailer will pull the cable as it breaks free of your vehicle. The switch will activate the battery and apply the trailer brakes strongly.



A surge brake system is entirely self-contained on the trailer and is activated when the towing vehicle decelerates. It operates very similar to your vehicles braking system. The momentum of the trailer pushes the surge brake housing forward acting like a foot on a brake pedal. The entire activation process is completed in less than one second.