Trailer Brake Controller Gain Calculator

A trailer brake controller's gain setting controls how much braking force is sent to the trailer's wheels — set it too low and the trailer pushes your vehicle, set it too high and the trailer drags. Enter your vehicle towing capacity and actual loaded trailer weight into the Trailer Brake Controller Gain Calculator to get your recommended gain setting as a percentage. Secondary outputs include your towing capacity utilization and estimated brake force required.

Results

Recommended Gain Setting

Towing Capacity Utilization

Estimated Brake Force Required

Results Table

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Frequently Asked Questions

What is trailer brake controller gain and why is it important?

Trailer brake controller gain determines how much braking force is applied to your trailer's electric brakes. Proper gain setting ensures your trailer brakes proportionally with your vehicle, preventing jackknifing, premature brake wear, and maintaining control during stops.

How do I determine the correct gain setting for my trailer?

Start with the calculated percentage as your baseline, then fine-tune through testing. Begin at a lower setting and gradually increase until you achieve smooth, proportional braking without wheel lockup or insufficient braking force.

Should I adjust my gain setting based on different loads?

Yes, you should adjust your gain setting whenever your trailer load changes significantly. A heavier load requires higher gain for adequate braking, while a lighter load needs lower gain to prevent wheel lockup.

What happens if my gain setting is too high or too low?

Too high: trailer brakes lock up, causing tire wear and loss of control. Too low: insufficient trailer braking, longer stopping distances, and excessive wear on your vehicle's brakes. Both scenarios are unsafe.

How can I test if my gain setting is correct?

Perform a controlled test at low speeds in a safe area. The trailer should brake smoothly without locking up or pushing the tow vehicle. Your vehicle and trailer should stop together as one unit.

Do weather conditions affect my brake controller gain setting?

Yes, wet or icy conditions may require lower gain settings to prevent wheel lockup. Always test your braking in a safe area when conditions change and adjust accordingly.

How often should I check and adjust my brake controller gain?

Check your gain setting whenever you change trailers, significantly alter your load, or notice changes in braking performance. Regular testing ensures optimal safety and brake system longevity.