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.
Product Page this Question was Asked From
Hopkins 7-Way RV Style Connector with Molded Cable - Trailer End - 8' Long - RV Standard
- Trailer Wiring
- Trailer Connectors
- Trailer End Connector
- 7 Blade
- Plug and Lead
- Hopkins
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on Trailer Wiring
Mark C.
5/26/2025
Do you offer a 7 pin pigtail with 10g brake wire?