Oyviny 4-Way Trailer Wiring Harness for Chevy Express & GMC Savana 55540 — Direct-Fit, Copper

Oyviny's 4-way trailer wiring harness 55540 adds a ready-to-use 4-flat connector to compatible Chevy Express and GMC Savana vans for reliable trailer lighting hookups.

If you tow trailers with a Chevy Express or GMC Savana from model years covered, this custom-fit harness gives you a factory-style 4-way connector without cutting into factory wiring. The kit is built with pure copper conductors, an ABS connector body, a rubber dust cover and a protective nylon sleeve so the assembly resists corrosion, abrasion and weather exposure. It plugs into the vehicle's existing trailer wiring ports and delivers turn signals, brake lights and tail lights to most trailers that use a standard 4-flat plug.

How does this harness fit my Chevy Express or GMC Savana?

The Oyviny 55540 harness is designed to match the factory wiring connections on specific Express and Savana models, making installation quick and clean. It accommodates 1500, 2500 and 3500 series vans across the model years listed and avoids cutting or splicing factory wires.

• Direct-fit compatibility for specified model years: 2003–2014 for some 1500 models and 2003–2023 for 2500/3500 variants.
• Plugs into existing vehicle connector—no permanent modifications required.
• 80-inch lead length gives installation flexibility behind bumpers or under chassis.

What signals and trailer lights will this 4-way connector support?

This standard 4-flat connector carries the basic lighting circuits used by most small trailers: tail/running lights, left and right turn signals, and brake lights. It doesn’t include separate circuits for electric trailer brakes or a 12V auxiliary feed—those require a different harness.

• Transmits turn signals, brake lights and tail lights reliably to the trailer.
• Compatible with common 4-flat trailer plugs used on utility trailers, boat trailers and small campers.
• Not designed for trailer brake controllers or dedicated 12V power—use an expanded harness for those functions.

Is the Oyviny 55540 durable for outdoor and towing use?

Yes—the harness combines solid mechanical and material choices to withstand the rigors of towing and outdoor exposure. Copper conductors ensure consistent electrical performance while the ABS housing and rubber dust cover protect the connector face from moisture and debris.

• Pure copper wiring for good conductivity and lower voltage drop.
• ABS connector body resists impact; rubber dust cover seals the socket when not connected.
• Black nylon net tubing shields the cable from abrasions and UV exposure.

How easy is it to install the wiring kit?

Installation is straightforward: the harness arrives with vehicle-compatible plugs so you can connect it without cutting or splicing factory wires. Typical installations take minimal time and don’t require advanced electrical tools, though a quick test with a trailer or lamp is recommended after hookup.

• Plug-and-play design fits factory sockets—no wire splicing needed.
• 80-inch cable length offers routing options around frame and bumper area.
• Includes a protective dust cap to keep the socket clean when not in use.

Who is this for: The Oyviny 4-way trailer wiring harness 55540 is aimed at van owners who need a simple, reliable 4-flat trailer connection for towing lights—especially owners of Chevy Express and GMC Savana 1500/2500/3500 models within the listed years. It’s ideal for contractors, small-fleet operators and recreational users who want a durable, no-cut installation to power trailers that rely on standard 4-way lighting circuits.