Parts Needed to Add a 7-Way Trailer Connector to a 2008 Ford F-150

Question:

I have the brake contoller and the factory connection under the steering column. I have a factory installed 4 pin connector on my truck already. Apparently there is a pig tail that I can just plug in the trailer connection under the rear of the truck that will convert my 4 pin connector to a 7 pin connector for trailer brakes. I need the part number to that pig tail and any installation instructions. I heard etrailer has them instead of me going to Ford. Any help would be appreciated. Thank You

asked by: Gary N

Expert Reply:

Since your 2008 Ford F-150 came with a factory installed 4-Way, you will need to add the 4-Way to 7-Way Adapter, # 37185. The 4 way you have on the truck will plug into the back of this adapter leaving 4 wires to hardwire.

The white wire will attach to the truck frame, the purple wire will attach to the reverse light circuit behind one of the tail lights. If reverse lights are not needed on the trailer, this wire can be tapped up and stowed out of the way.

For the blue and black wires, you will need about 25 feet of wire # 10-2-1. Attach the black wire from the adapter to the black wire in the harness. Attach the blue wire on the adapter to the white wire in the harness. Route the wire under the truck, avoiding areas that may pinch or burn the wire, to the engine compartment.

Under the hood, separate the 2 wires and route the blue one through the firewall into the cab of the truck and near where the brake controller plugs in. Cut the blue wire from the back of the brake controller so that you still have enough wire to attach it to the wire you routed through the firewall.

Next, you will go back under the hood and connect the black wire first to a 40 amp circuit breaker, # PK54540, and then from the circuit breaker to the positive battery terminal.