Trailer Brake Controller Guide
Find out whether your trailer legally requires a brake controller and which type — proportional or time-delayed — best suits your trailer weight and axle count.
Trailer Brake Controller Guide
GVWR · Axles → Controller required? Type recommendation
How It Works
US federal regulations require electric trailer brakes and a controller for trailers with a GVWR at or above 3,000 lb. The calculator applies this threshold plus weight-based logic to recommend proportional (inertia-sensing) or time-delayed (user-adjustable ramp) controller types, with brand suggestions for each tier.
How to Use This Calculator
- Find your trailer’s GVWR on the VIN plate attached to the trailer tongue or frame.
- Count the number of axles on your trailer that have electric drum or disc brakes.
- Enter both values and click Check Requirements.
- Review the recommendation and safety note for your weight class.
- Verify your result against your specific state or province regulations, which may set a lower threshold.
Worked Example
Reference Table
| Trailer GVWR | US Requirement | Controller Type | Suggested Brands | Notes |
|---|---|---|---|---|
| Under 1,000 lb | Not required | N/A | — | Small utility trailers, motorcycle trailers |
| 1,000–2,999 lb | Not federally required | Time-delayed (if fitted) | Tekonsha Voyager, CURT 51110 | Some states require at 1,500 lb; check local law |
| 3,000–5,999 lb | Required (federal) | Time-delayed or proportional | Tekonsha P3, Hayes Syncronizer | Proportional recommended for tandem axle |
| 6,000–9,999 lb | Required | Proportional | Tekonsha P3, Curt Echo, Reese Pro Series | Proportional essential for safe control |
| 10,000–14,999 lb | Required | Proportional (high-output) | Tekonsha P3, Curt Echo, Reese Towpower | Ensure wiring rated for dual-axle load (12+ AWG) |
| 15,000+ lb (gooseneck/5th wheel) | Required | Proportional — 3+ axle capable | Tekonsha Prodigy P3, Hayes Endeavor | Verify tow vehicle brake output capacity |
Frequently Asked Questions
What is the difference between proportional and time-delayed controllers?
A proportional (inertia-sensing) controller uses an internal accelerometer to detect vehicle deceleration in real time and sends a proportional brake signal to the trailer — the harder the tow vehicle stops, the harder the trailer brakes apply. A time-delayed controller sends a pre-programmed ramp of increasing current to the trailer brakes over a set time. Proportional is smoother, reduces wear, and performs better in emergency stops. Time-delayed is less expensive and simpler to install and adjust.
Does my state require a brake controller at a different weight than 3,000 lb?
Yes — several US states set lower thresholds. For example, California requires brakes on trailers over 1,500 lb GVWR; Washington requires them over 3,000 lb net weight. Canada requires trailer brakes at 2,000 kg (4,409 lb) GVWR federally. Always verify the specific regulation for the states or provinces you will be towing through.
Can I use a wireless or Bluetooth brake controller?
Yes — portable Bluetooth/wireless proportional controllers like the Curt Echo and Draw-Tite Pilot clamp to the dash or windshield and communicate wirelessly with a module in the 7-pin trailer connector. They are especially useful for rental trailers, boats, and vehicles without a factory brake-controller port. Performance is comparable to hardwired units for typical towing.
How do I know if my trailer has electric brakes installed?
Electric drum brakes have a 7-pin or 4-pin flat trailer connector with a dedicated blue wire (brake output). You can also look at the wheel hub — if there is a breakaway battery box mounted on the trailer tongue and a 7-pin connector, electric brakes are almost certainly fitted. Hydraulic surge brakes do not use a trailer brake controller.
