6-foot wiring harness kit that mounts in your truck bed and taps into the truck's factory wiring, giving your 5th wheel trailer an easy 7-pole hookup for lights, brakes, and turn signals. A reinforced, weather-sealed lid keeps connections protected out on the road.
The Blue Ox BX88356 is a 5th wheel wiring harness kit designed to mount in the bed of your truck, tapping into the truck's factory wiring to give you an easy hookup point for your 5th wheel trailer. It includes a 6-foot wire harness and a 7-pole trailer socket, covering the connections needed for lights, brakes, and turn signals.
The kit's Easy-Grip lid is reinforced and opens a full 180° for easier access when making connections, while internal seals and a reinforced 90° angle help protect the connection from weather and wear during towing.
Covers lighting, brake, and turn signal connections
Sized to route from factory wiring to the truck bed mount point
Internal seals protect connections from the elements
Reinforced lid opens a full 180° for easier hookups
This kit is designed to mount in the bed of the truck and uses the truck's existing factory wiring to power the 5th wheel connection. SKU: BX88356 | Harness Length: 6' | Socket Type: 7-Pole
This kit is designed to tap into your truck's existing factory wiring — confirm your truck has a compatible factory wiring setup before ordering. Do not install or operate this equipment until the installation instructions have been read and understood. California Prop 65 Notice: This product can expose you to chemicals, including DEHP, known to the State of California to cause cancer, birth defects, or other reproductive harm.
General Installation Steps (Professional Installation Recommended): 1. Locate Factory Wiring: Identify the truck's factory wiring connection point 2. Mount the Socket: Secure the 7-pole socket housing in the truck bed 3. Route the Harness: Run the 6' harness from the factory wiring to the mounted socket 4. Secure Wiring: Use the included cable ties and screws to fasten wiring in place 5. Test Connections: Confirm lights, brakes, and signals function correctly before towing
In The Box: • 6' Wire Harness • 7-Pole Trailer Socket • Cable Ties • Mounting Screws