Brake Controllers

Choosing a brake controller and electric brake parts

Three different products hide under this heading: the controller that signals a trailer to brake, the supplemental system that brakes a car you're flat-towing behind a motorhome, and the hardware that clamps the axle. Sort out which one you're shopping for first, because none of them substitute for another.

• Proportional vs. time-based controllers. A proportional controller senses how hard your tow vehicle is decelerating and matches the trailer to it, so stops feel smooth. The Redarc Tow-Pro Elite is dual-mode — proportional for normal towing, plus a user-controlled mode you can dial in — and handles 1 to 3 axle trailers.
• Axle count and weight. Match the controller to the number of braked axles. A heavier tandem- or triple-axle trailer draws more current, so confirm the controller is rated for the load you actually pull.
• Supplemental braking for flat-towing. If you tow a car behind a motorhome, that's a separate system. The Demco Air Force One ties into the coach's air brakes to press the towed car's pedal, and the Demco Coach Link gives you a wireless monitor so you know it's braking.
• Electric brake assemblies. The brakes themselves wear out. Dexter electric brake assemblies come in 12" x 2" for 7,000 lb axles in right- and left-hand versions — order the correct side, they aren't symmetrical.
• Shoes and linings. If the backing plate is still good, a shoe and lining kit is the cheaper fix. AP Products stocks 10" x 2-1/4" and 12" x 2" kits for common Dexter and Lippert axles.
• Vehicle-specific mounting. Some controllers use a factory-look dash plate — the Redarc switch insert panel drops into GM and Isuzu dashes cleanly instead of hanging a knob under the column.

Pair a new controller with a working breakaway system and clean trailer connectors, since the controller does nothing if the signal never reaches the brakes. Upgrading the whole tow setup? The hitch and coupler is the next thing to check.