Trailer Wiring for 1991 Chevy C2500
Updated 10/30/2025 | Published 10/03/2025
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Question:
I have a 1991 C2500. Has existing harness and seven pin trailer plug but is wired with non weatherproof scotch locks. Looking for a new harness and 7 pin receptacle with proper weatherproof splice connectors. Entire truck was wired with wrong color wires to the rear receptacle. Making any future diagnosis very difficult if I have a wiring problem. Any recommendations on your products would be greatly appreciated. Thank you
asked by: Paul
Expert Reply:
Hey Paul! Are you wanting to still use the factory wiring port on your truck? If you are, you can use the # C55315 for a 4-way and then upgrade to a 7-way with the # ETBC7. If you want a universal 4-way to bypass that wiring you can use the Curt # C59236 instead. The # ETBC7 comes with everything you need, including waterproof quick splices, for installation.
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Product Page this Question was Asked From
Curt T-Connector Vehicle Wiring Harness with 4-Pole Flat Trailer Connector
- Custom Fit Vehicle Wiring
- Trailer Hitch Wiring
- Vehicle End Connector
- No Converter
- No Tow Package
- 4 Flat
- Plug and Lead
- Plug-In
- Visible
- CURT
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Robin H.
10/30/2025
Hey Paul, how did things turn out with the new wiring setup on your C2500 using the Curt harness and ETBC7 kit? Your update could make it easier for the next person trying to clean up their trailer wiring.