Electric Brakes Guide
Electric Trailer Brakes: Setup, Use, and Gain Setting
If you’ve never towed a trailer with electric brakes before, this page is for you. The technology is simple, the setup takes 30 seconds, and the difference in how your rig stops is night and day.
Why your trailer has brakes
Texas requires brakes on any trailer with a gross weight over 4,500 lbs (Texas Transportation Code §547.401(b)). In our fleet, that means the 14′ hydraulic dump, 20′ car & equipment hauler, 24′ full-tilt deckover, and 30′ deckover with mega ramps all have electric brakes. The 20′ enclosed cargo and the two 16′ utilities don’t — they’re under the threshold.
Why brakes matter beyond the legal requirement: your truck’s brakes were designed to stop your truck. Add 5,000 lbs of trailer and the math changes. Trailer brakes let the trailer help stop itself, which means your truck’s brakes last longer, you don’t overheat them on long descents, and your stopping distance shrinks dramatically.
How electric brakes work (the 60-second version)
Each braked wheel has an electromagnet inside the drum. When you press your truck’s brake pedal — or activate the manual slider on your brake controller — current flows through the trailer’s wiring to the magnets, which engage the brake shoes against the drum. More current = harder braking.
The amount of current is set by your brake controller (in the cab of your truck) using a setting called gain.
Brake controllers — built-in vs. portable
Most modern trucks (Ford, Ram, GMC/Chevy, Tundra from 2007+) have a brake controller built into the dash near your knee. It looks like a little screen or a slider switch labeled “Trailer.”
If your truck doesn’t have one, you can install an aftermarket controller, or — for the trailers in our fleet equipped with the Elecbrakes wireless system — control them from your phone.
The Elecbrakes wireless system
Several of our trailers use the Elecbrakes wireless brake controller — a Bluetooth unit mounted on the trailer that pairs to your phone. It eliminates the need for a brake controller in your truck. To use it:
- Plug the trailer 7-pin into your truck normally.
- Download the Elecbrakes app from your device’s app store — free.
- Open the app in your truck cab. The unit pairs automatically.
- Confirm the connection icon shows the trailer is paired and getting power.
- Set your gain (see below).
- Test before leaving the yard.
The Elecbrakes manual is linked from elecbrakes.com if you need a deeper reference.
Setting the gain — the most important step
Gain controls how much braking power the controller sends to the trailer. Set too low, the trailer doesn’t help you stop. Set too high, the trailer brakes lock up and skid — which can cause sway, jackknife, or a flat-spotted tire.
The procedure for setting gain
- Park in a safe, empty area — empty parking lot, frontage road, our yard.
- Start with the gain low — around 4 or 5 on most controllers (out of 10).
- Accelerate to about 20–25 mph.
- Slide the manual brake controller all the way over (don’t use the truck’s brake pedal). This sends 100% of the set gain to the trailer brakes only.
- What should happen: the trailer should brake firmly and slow the whole rig in a straight line. You should feel the trailer braking, but the tires shouldn’t lock or skid.
- If the trailer locks up (you’ll hear it, feel it, or see skid marks in the mirror) → reduce gain.
- If you barely feel the trailer braking → increase gain.
- Repeat until the trailer brakes feel firm but don’t skid.
Reset gain when the load changes. An empty trailer needs less gain than the same trailer loaded with 4,000 lbs of equipment. Re-set gain whenever the load weight changes significantly.
Manual slider — your emergency tool
The manual slider on your brake controller (or the app for Elecbrakes) lets you apply only the trailer brakes, without using your truck’s brakes. This is enormously useful in two situations:
- Sway — a light tap of trailer-only braking pulls the trailer straight behind you. This is the textbook anti-sway maneuver. See our Emergency Guide.
- Long descents — instead of riding your truck’s brakes downhill (which heats them up and reduces effectiveness), apply gentle trailer brake to share the load.
What if the brakes don't work?
Before leaving the yard, manually slide the controller. You should feel the trailer pull back against your truck. If you don’t feel anything:
- Check the 7-pin connection on both ends.
- Check that the brake controller is plugged in and on.
- For Elecbrakes, check that the app shows a connection.
If you’ve verified all that and there’s still no brake response, don’t drive. Call us at the number on your rental agreement and we’ll come out.
How to Attach a Trailer
Emergency Guide
Texas Towing Regulations
