Custom Towed-Vehicle RV Wiring Harness (20-26 Sierra 3500 HD)Find parts that fit my vehicle

Custom Wiring Solution. The Custom Towed-Vehicle RV Wiring Harness provides a reliable electrical connection between a towed vehicle and an RV using a standard 4-way flat trailer plug. Designed for ease of use, it enables the vehicle’s existing lighting system to function in sync with the RV’s signals, ensuring safety and compliance while towing. This harness is essential for maintaining proper brake light, turn signal, and taillight operation on the towed vehicle during travel.

Construction and Appearance. Constructed from durable thermoplastic rubber, this harness offers resistance to environmental factors and wear. The design integrates block diodes to protect sensitive vehicle electronics from electrical malfunctions caused by RV signals, ensuring longevity and reliability. The components include a 4-flat extension, a mounting bracket, and all necessary hardware, finished for practical and secure installation.

Installation. Installation is straightforward due to the plug-and-play design that eliminates the need for cutting or splicing wires. No drilling is required, making the harness suitable for quick setup and removal without vehicle modification.

Warranty. This product includes a one-year limited warranty, providing assurance of quality and durability.

Application. Specifically fits the 2020–2026 Sierra 3500 HD, allowing direct connection to compatible models in this range without additional modifications.

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