CURT 56020 4-Way Flat Trailer Wiring Harness for Ford E-Series (E-150/E-250/E-350) — Vehicle-Side Plug-In, No Splice

The CURT 56020 is a vehicle-specific, plug-and-play 4-way flat trailer wiring harness built to add a clean, OEM-style trailer connector to select Ford E-Series vans.

If your E-150, E-250 or E-350 doesn’t already include factory trailer wiring, this custom T-connector installs without cutting or splicing and provides a standard 4-flat socket for tail, brake and turn signal circuits. Designed to match OEM connectors and routed to the taillight assembly, the CURT 56020 streamlines towing setup while keeping the vehicle’s wiring intact and factory appearance preserved. A dust cover and all necessary wiring components are included to protect the connector and ensure reliable connection over time.

How does this harness install on my Ford E-Series?

Installation is a straightforward plug-in process that uses vehicle-specific adapters to mate with your E-Series taillight harness. You simply access the factory connectors, unplug, and plug the CURT T-connector in line—no cutting, soldering, or tapping required. The harness is shaped to follow factory routing for a neat, secure fit.

• Vehicle-specific OEM-compatible connectors for direct plug-in
• Designed to interface with taillight assembly connectors
• No splicing or permanent wire modifications needed
• Includes dust cover to protect the connector

What lights and signals does the 4-way flat support?

The CURT 4-way flat provides all basic trailer lighting functions: running lights, brake lights, and left/right turn signals. It delivers the standard circuits required by most small trailers, utility trailers, and boat trailers. If you need reverse or electric brakes, a different harness or an adapter will be necessary.

• Tail/running lights and marker lights compatible
• Brake lights and turn signals fully supported
• Standard 4-way flat output for common trailer plugs
• Not configured for brake controllers or 7-way functions

Will this harness be durable and weather resistant?

CURT builds its custom harnesses for road use and exposure to elements; the 56020 includes protective features to keep the connector working over time. The dust cover helps prevent corrosion and debris buildup when the trailer is not connected, and the wiring components are made to withstand normal under-vehicle conditions. Follow basic maintenance like periodic inspection for best long-term performance.

• Dust cover included to block moisture and dirt
• OEM-style connectors reduce looseness and arcing risk
• Wiring and terminals rated for towing loads typical of 4-way systems
• Regular checks recommended for longevity

Do I need tools or other parts to complete installation?

Most installations require only basic hand tools to access the taillight area and secure the harness. The CURT 56020 supplies the plug-in wiring and dust cover; you generally won’t need additional wiring parts. If your trailer requires more circuits (e.g., electric brakes or 12V auxiliary), plan to add an appropriate 7-way converter or brake controller wiring.

• Basic tools for removing taillight panels or access caps
• All primary wiring components included with the harness
• Optional adapters or controllers needed for extra functions
• Refer to vehicle application guide to confirm fitment

Who this is for: The CURT 56020 is ideal for Ford E-150, E-250 and E-350 owners who want a quick, non-invasive way to add standard trailer lighting. Choose this harness if you value a factory-style connection, minimal installation time, and a tidy wiring solution for towing small to medium trailers without modifying your vehicle’s original wiring.