Adapting 2010 Ford E-350 With 4-Pole Wiring Harness to Tow Boat Trailer With 5-Pole Flat Connector

Updated 01/30/2014 | Published 01/27/2014

Products Featured in This Question

Tekonsha Plug-In Wiring Adapter for Electric Brake Controllers - Ford

(349)

$19.28

Hook Probe Circuit Tester

(66)

$12.94

Question:

I have a 2010 Ford E-350 Extended Passenger Van that I would like to set up to tow my boat which requires a flat 5-pin wire harness. The vehicle was not equipped with a hitch or any wiring at the rear when I purchased it. I have previously purchased a class IV hitch and 4-pin OEM harness from e-trailer. They are installed and work great. However, I now need the 5th pin reverse lights for the disc brakes on my new boat trailer. I purchased the 7-pin OEM harness and attempted to install it tonight, only to find that the van is not equipped with the factory harness to plug into. My plan was to install the 7-pin and just use an adapter down to 5-pin. Could you please advise on the best course of action from here. My goal is to be able to use a 5-pin flat plug. Whether that is through an adapter from 7, it does not matter. Thanks,

asked by: Bryan

Expert Reply:

There are several ways to adapt your different tow vehicle and trailer connectors.

The most cost-effective method to put a 5-pole flat connector on your vehicle is to use Hopkins 4 Pole to 5 Pole Trailer Wiring Adapter, part # 47515. Installation is simple and consists of connecting your existing 4-pole and making one single splice connection to the reverse light circuit at the back of the van. You can use a circuit tester such as # PTW2993 to confirm which wire carries the reverse light signal when the vehicle is shifted into reverse.

Another method is to install a 7-way and use an adapter. Hopkins part # 37185 will plug in to your existing 4-pole; you will then need to connect the white ground wire to the vehicle frame (to a clean bare metal surface) and the purple wire to the reverse light circuit on the E-350. (Black and blue wires are not used in this case.) A quick-splice connector is provided. Then you can plug in adapter # 37385 to get your 5-pole connector.

I suggest you confirm that the combined weight of your boat and trailer is within the towing capacity for your 2010 Ford E-350 Extended Van. This vehicle can be equipped with several engine sizes: 5.4L V8, 6.8L V10 and 6.0L V8 Turbo Diesel. Tow ratings vary from a low of 7200-lbs to a maximum of 10,000-lbs; please refer to your owners manual to ensure your version is capable of towing your boat/trailer load. Your Draw-Tite hitch is also rated for 10,000-lbs gross towing capacity unless used with a weight distribution system, which increases its capacity to 12,000-lbs.

expert reply by: Adam R