How to Install a 7-Way on a 2010 Ford F150 with a Factory 4-Way

Updated 04/01/2015 | Published 03/31/2015

Question:

I have a 2010 ford F150 supercrew that has an existing 4 pin plug for towing. The truck does have the towing package. I want to add a 7 blade connection and keep the 4 pin as well. What type of wiring harness will I need/

asked by: Todd

Expert Reply:

To install a 7-way in your 2010 Ford F-150 with a factory 4-way all you would need is the # 37185. This will plug into the 4-way you currently have and will give you both a 4-way and a 7-way at the rear of your truck. To complete the 7-way wiring you will need to tap into a couple wires under the rear of your truck.

Follow the 4-way trailer connector wires from the trailer connector to the front of the vehicle. These wires connect to a factory plug along the frame rail, usually on the driver's side, between the back tires and the rear bumper. The factory plug should be mated to another connector which has wiring that continues back toward the bumper.

There are more wires coming from the front of the vehicle than there are coming out toward the 4-Way plug. Ford wires the front of the vehicle as if it will be manufactured with a 7-Way plug, so all the 7-Way wires are run to this connector on the frame rail. This allows a 7-Way wiring harness to simply plug in line with the wiring coming from the front of the vehicle. If the vehicle were made with a 4-Way plug, it would plug into the same connector. Because a 4-Way plug would not require them, the additional wires are terminated at the pictured set of mated connectors.

expert reply by: Jameson C