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Trailer Brake Gain Guide & Adjustment Tool

Brake gain cannot be calculated from trailer weight. Use this preparation checklist alongside your exact equipment manuals, not instead of their procedure.

1. Start with the exact manualsIdentify the vehicle, controller and brake system. Read their compatibility and setup instructions; gain scales and procedures differ.2. Resolve equipment or service issuesConfirm the connected braking system is ready under its manuals. Do not attempt to compensate for a fault with a higher gain setting.3. Review the documented test procedureUse the speed, surface, conditions and adjustment method in your manuals, in an area clear of vehicles and pedestrians. Use this page while parked, never during a driving test.4. Record observations and recheckAfter the manual-led test, record the response. Stop for faults, weak braking, harshness or locking and consult the manual or a qualified service professional. Recheck when load or conditions change.

Current setting — optional note

Copy the controller’s own scale. This entry is not a recommended setting.

Test observations — optional

Record while parked. Notes disappear on reset, navigation or refresh.

No settings are sent to a controller or stored permanently.

Checklist status

0 of 4 preparation items recorded.

Why trailer weight cannot produce a gain setting

A controller’s gain setting changes its brake output, but the scale is controller-specific. Brake system, condition, load and test conditions also matter. A universal trailer-brake gain chart would conceal those differences. This tool records preparation and notes, not a prescribed setting.

How this adjustment tool works

Begin with your exact vehicle, controller and brake manuals. Dexter’s electric-brake guidance requires manufacturer instructions and road testing away from vehicles and pedestrians. Its procedure is not a universal instruction for every brake or controller. Use the test speed and method for your equipment, and operate this checklist only while parked.

Worked example

An owner locates the exact manuals, checks equipment readiness, reviews the documented test conditions, then records observations while parked after following that procedure. Checking all four items records those steps. It does not generate a gain setting or confirm braking performance.

Illustrative scenario, not a manufacturer specification or approval.

How to interpret the result

A checked item means you recorded that preparation step. Even all four checked items do not verify brake performance or approve towing. The optional setting note is copied from your own controller; it is neither validated nor adjusted by this website. Notes are temporary and disappear on refresh, navigation or reset.

Common mistakes

Copying another trailer’s gain number without following your controller instructions.
Trying to solve a service fault by simply raising gain.
Treating tire lockup as a universal goal.
Using a driving test area with vehicles or pedestrians present.

Frequently asked questions

Is there a trailer brake gain chart by weight?

There is no universal chart used here. Use the starting point and adjustment procedure in the documentation for the exact vehicle, controller and brake system.

What if the brakes lock or braking feels weak?

Stop the test and follow the equipment’s troubleshooting and adjustment instructions. Seek qualified service if performance or system condition is uncertain; this page does not diagnose the cause.

Can the checklist set my controller?

No. It has no connection to your vehicle or brake controller, performs no gain arithmetic, and does not save settings permanently.

Sources and scope

Primary guidance reviewed September 28, 2026. Manufacturer labels and the manuals for your exact equipment take precedence.

Dexter electric-brake guidance, hosted by NHTSAPrinted pages 11–12: How to Use Your Electric Brakes Properly and Synchronizing Your Trailer Brakes. Follow your exact equipment manuals.