What Gauge Wire Should be Used to Wire Trailer Brakes
Updated 05/26/2025 | Published 06/23/2014
Question:
Hi, etrailer recommends to using Deka 10-2 gauge wire for running electric brakes to a tandem axle trailer. If this is the case, why does 7-way harnesses with molded plugs only have 12 gauge wiring for the brakes? Tghanks,
asked by: Ray S
Expert Reply:
That's a very good question, we tend to be extra cautious and say to use 10 gauge wire because that would be more than enough. When you get into longer trailers that will end up using a lot of wire the heavier gauge wire becomes more necessary. On a smaller trailer with a single axle of brakes 12 gauge wire would probably be enough. But for a longer tandem axle trailer I would recommend you run 10 gauge wire to all the assemblies just to minimize the amount of resistance that would be on the circuit.
Also, be sure to use clean metal surfaces for your grounding locations.
Featured Help Information
Miscellaneous Media
Continue Researching
- Shop: Brake Controller
- Article: Trailer Wiring Diagrams
- Search Results: trailer wiring
- Search Results: trailer breakaway kit
- Shop: Trailer Wiring
- Shop: etrailer Trailer Wiring 7-Way Upgrade Kit w/ Junction Box and RV Style Connector
- Shop: Dexter Nev-R-Adjust Electric Trailer Brakes - 10" - Left/Right Hand Assemblies - 3.5K
- Search Results: trailer brakes
- Shop: etrailer Electric Trailer Brakes - Self-Adjusting - 10" - Left/Right Hand Assemblies - 3.5K
- Shop: 12 Gauge 2 Conductor Jacketed (Brake) Wire Per Foot
- Shop: Trailer Wiring Junction Box - 7 Color Coded Terminals - ABS
- Shop: Easy Grease Trailer Hub and Drum Assembly for 3.5K Axles - 10" - 5 on 4-1/2 - Pre-Greased
- Shop: Trailer Hitch
- Shop: Deka Jacketed 2 Wire, 10 Gauge, Brake Wire - per Foot
- Shop: Suspension Enhancement
- Q&A: Instructions to Wire a Trailer for Electric Brakes
- Search Results: levels
- Search Results: water pumps
- Search Results: fireplace
- Search Results: wire
- Q&A: Is 14 Gauge Wire Too Small for Electric Trailer Brakes
- Article: Wiring Trailer Lights with a 7-Way Plug (It's Easier Than You Think)
- Article: Trailer Lighting Requirements
- Article: 4 Steps to Choosing Your 5th Wheel Pin Box
- Article: How to Measure Your Trailer Wheel Bolt Pattern
- Video: Review of Lippert Trailer Hubs and Drums - ABS Trailer Hub And Drum Assembly - LC44PX
- Video: Feature Breakdown: Jacketed 2 Wire (Brake Wire)
- Video: Feature Breakdown: TruRyde Electric Trailer Brakes
- Q&A: Why is 10 or 12 Gauge Wire Recommended for Electric Brake Assemblies
- Video: Trailer Brakes and Wiring Installation
on Trailer Wiring
Mark C.
5/26/2025
Do you offer a 7 pin pigtail with 10g brake wire?