Parts Needed To Convert Triple Axle Boat Trailer From Hydraulic To Electric Brakes  

Question:

Expert Reply:

Hello Edward, I can definitely point you in the right direction. Generally, we do recommend using hydraulic brakes for a boat trailer, since electricity and water do not mix well. If you want to add electric brakes, you will need electric trailer brake assemblies, hub/drum assemblies, a 7-way trailer wiring harness, an emergency breakaway kit, and an electric trailer brake controller for your vehicle.

In order to recommend the correct parts, I will need more information on your trailer. In order to select the correct brakes and hubs I will need to know your axle weight capacity, your inner and outer bearing sizes, and your wheel bolt pattern. If you can provide me with that info I am happy to make a recommendation.

For example, the etrailer Electric Trailer Brakes # AKEBRK-7-SA are for the typical 7,000 lb axle. These are generally used with the hub # AKHD-865-7-2-EZ-K which uses a # 25580 (1.75" inner diameter) inner bearing and a # 14125A (1.25" inner diameter) outer bearing. It also has the 8 on 6-1/2" lug bolt pattern. Here are the rest of the parts I recommend for your conversion:

- Hopkins 7-Way Molded Trailer Wire Connector - 11' Long # HM20048

- Trailer Wiring Junction Box - 7 Terminals - Polypropylene # 3375601100

- Bright Way Push-to-Test Trailer Breakaway Kit with 1-Amp Charger and 5 Ah Battery - Top Load # 3802308

- Tekonsha Prodigy P3 Trailer Brake Controller - 1 to 4 Axles - Proportional # 90195

We have an article that goes over the process of adding electric brakes in detail. You will find this article linked below if the "featured help information" section.

expert reply by: Jesse M

0

Jesse M.

2/17/2026

Hey Edward, were you able to gather the axle weight, bearing sizes, and bolt pattern for your boat trailer? Once you have those details, I can help narrow down the right electric brake parts for your conversion. Let me know what you find so we can get you set up correctly.