Just traded my '08 E350 in on an '11. I have to wire it for trailer lights without a brake controller. Does anybody know the part # for the factory wiring harness and terminal that's mounted to the bumper on vans with factory towing package? I can't get it to come up on fordparts.com. I got lucky when I bought my '08 and there was a dealer selling one on ebay at the time. The new ones are a little nicer though. On the '11 models with trailer towing there are 2 receptacles with flip open covers, one 4 pin flat and one 7 pin round. I definitely want the ford part so I don't have to hack into the factory harness.

 

Moved to the 1968 - Present Full Size Van forum.

 

I have a 2010 without the factory trailer tow package. If you crawl under the van at the back, there is an unused connector on the driver side frame rail by the spare tire. You can splice into the wires on that connector for your 4 pin trailer harness. I used a test light to see witch wires I needed, and splice connectors to tap the wires without having to cut them.