Do Electric Trailer Brakes Need 10 Gauge Or 12 Gauge Wiring?
Updated 10/10/2026 | Published 10/08/2026
Products Featured in This Question
Question:
Do you make these cables in house? I have a 10 gauge wire going to my trailer brakes, just wondering if you can make a cable with a 10 gauge instead of 12 gauge for the trailer brakes? The rest of the wires within part e99010 are just what I need. Or will the 12 gauge wire work effectively with the 10 wire to the brakes? Thank you!
asked by: Shawn A
Expert Reply:
Hi Shawn!
Trailer brake wire is typically 10 or 12 gauge, but either will honestly work. The 7-Way RV Style Connector with Molded Cable - Trailer End - 6' Long - RV Standard # e99010 is made for us (not in-house) and uses 12 gauge for the brake wire (blue), and we cannot change that, unfortunately.
However, you could use the following two options to make your own 7-Way for your trailer:
Spectro Jacketed ABS Trailer Cable Per Foot # SWC89FR
Optronics 7-Way Round RV Style Trailer Connector - Trailer Side # A7WCB
The Spectro wiring uses 12 gauge for the black, brown, yellow, and green wires, 10 gauge for the blue and red wires, and 8 gauge for the white wire. It is by far the beefiest option we currently carry. You would just need to wire that to the Optronics 7-Way # A7WCB, but that's super easy and should really only take a couple minutes to get done.
If you don't need this super beefy wiring though, the # e99010 will be what you are looking for and will work perfectly fine.
On that note, what kind of trailer are you working on?
(click to enlarge)
Product Page this Question was Asked From
etrailer 7-Way RV Style Connector with Molded Cable - Trailer End - 6' Long - RV Standard
- Trailer Wiring
- Trailer Connectors
- Trailer End Connector
- 7 Blade
- Plug and Lead
- etrailer
more information >
Continue Researching
- Video: Complete Breakdown of the etrailer 7-Way RV Style Connector with Molded Cable
- Shop: etrailer 7-Way RV Style Connector with Molded Cable - Trailer End - 6' Long - RV Standard
- Shop: TowSmart 7-Way RV Style Connector with Molded Cable - Trailer End - 6' Long - RV Standard
- Shop: TowSmart 7-Blade Trailer Connector w/ Jacketed Cable - Trailer End - 72" Long
- Shop: Trailer Hitch
- Shop: Adco SFS AquaShed Trailer Cover for Bumper Pull Horse Trailers up to 16' Long - Gray
- Q&A: Which Trailer Floor and Wall Screws are the Best Recommendation for Rust Resistance
- Q&A: Recommendation for Transporting Motorcycle Using 2012 Dodge Grand Caravan
- Shop: Adco SFS AquaShed Trailer Cover for Bumper Pull Horse Trailers up to 10' Long - Gray
- Shop: etrailer Trailer Hitch Receiver - Custom Fit - Matte Black Finish - Class III - 2"
- Shop: Trailer Mate Trailer Hitch Receiver - Custom Fit - Class III - 2"
- Article: Trailer Wiring Diagrams
- Shop: Trailer Wiring
- Video: Curt T-Connector Vehicle Wiring Harness Review C56040
- Search Results: trailer hitch
- Q&A: What is the Difference Between a Class II and a Class III Hitch?
- Q&A: Lug Nut Torque Chart for Trailer Wheels
- Video: How to Choose a Trailer Brake Controller
- Article: Brake Controller 7- and 4-Way Installation Kit (ETBC7)
- Search Results: trailer wiring
- Shop: Suspension Enhancement
- Q&A: What is the Difference Between a 4-Way and 7-Way Trailer Connector
- Search Results: trailer tires and wheels
- Video: The Low-Down on the Curt Powered Tail Light Converter with 4-Pole Flat Trailer Connector
- Article: How to Measure for Trailer Hitch Drop
- Shop: Brake Controller
- Q&A: Installation Time for Blue Ox BX1128 Flat Tow Base Plate Kit for 2016 Jeep Grand Cherokee
- Article: How to Choose the Right Trailer Hitch Class
- Search Results: trailer jack
- Q&A: How to Replace a Lance 6-Pin Plug w/ a Standard 7-Way Connector
on Trailer Wiring
Gary
10/10/2026
I had used the old style round brake and signal light plug on my trailer since I bought it. It's an early 80s mileage utility trailer. My truck is equipped with the RV style connector. I always used an adapter to make the hook up. Those adapters, when working were easy but unreliable. I finally just wired in the RV harness and things are much easier and more reliable.