View Full Version : Seeking advice, alternate trailer wiring plug

03-09-2022, 08:21 PM
We have the typical side-of-the-truck-bed fifth wheel plug on our F-350. (I didn't install it, but I definitely use it!)

I need to have an *additional* outlet down at the bumper. (Have to pull a "regular" trailer next week.) That trailer is also a 7-blade, so I bought a split 7-blade/4-flat outlet (because you always need the 4-flat). Can I just "tap" into the wiring on the other plug for it? (Heat shrink, all that, yeah.)

Not sure what other way I'd do it, but I'm betting someone out there has done this before. Any advice welcome.

Note: This is not for trailer-behind-another-trailer. This is to have an alternate socket at the bumper.

03-10-2022, 11:07 AM
I always like to take the path of least resistance. Rather than going through the pain staking exercise of wiring, splicing, and maybe making a mistake along the way, also interfering with your truck wiring, why not just get something like this? If it were mine, this is what I'd do:

Click here (https://www.amazon.com/ONLINE-LED-STORE-Extension-Double-Prong/dp/B07G8QYWTB/ref=sr_1_50_sspa?keywords=7+pin+trailer+extension+ cord&qid=1646928201&sr=8-50-spons&psc=1&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUExR1pDNlFaRTgxQ0VBJ mVuY3J5cHRlZElkPUEwMzg0NjM4MUUxQ1hUTUg2RFhRSSZlbmN yeXB0ZWRBZElkPUEwMzA5NzM5MTVMU0M3TjIwQlFRUiZ3aWRnZ XROYW1lPXNwX2F0Zl9uZXh0JmFjdGlvbj1jbGlja1JlZGlyZWN 0JmRvTm90TG9nQ2xpY2s9dHJ1ZQ==)


Click here, slightly higher cost though. (https://www.amazon.com/Voilamart-Trailer-Extension-Connector-Trailer-8Feet/dp/B09MLNLWHS/ref=sr_1_51_sspa?keywords=7+pin+trailer+extension+ cord&qid=1646928201&sr=8-51-spons&psc=1&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUExR1pDNlFaRTgxQ0VBJ mVuY3J5cHRlZElkPUEwMzg0NjM4MUUxQ1hUTUg2RFhRSSZlbmN yeXB0ZWRBZElkPUEwMjU2NjExMjQzWlVVMjVVVjY3JndpZGdld E5hbWU9c3BfYXRmX25leHQmYWN0aW9uPWNsaWNrUmVkaXJlY3Q mZG9Ob3RMb2dDbGljaz10cnVl)

03-10-2022, 11:15 AM
OP here: Yeah, you're right. I have those parts, but running through the tailgate (we have a hard cover), wouldn't work as well. Turns out, the part i need is BU5Z-14489-AA. There's a hole in the bumper where it goes and a harness attachment right there, tucked away that I didn't see previously. Local Ford doesn't have it, but say they can have it tomorrow. I just have to drive 30 minutes one way to pay for it first. Ugh. But thanks for the help!

03-10-2022, 08:02 PM
Is the wiring harness a simply, plug it in and it works? So there's no cutting wires, splicing, and all that? If so, that's the better way to. It's attached permanently then.

03-10-2022, 08:12 PM
Exactly. Fitting the proper harness is the right way. I'm loathe to cut and splice when I don't have to! Not afraid to, but... so messy!

03-11-2022, 08:19 AM
I also would order the correct part from Ford. No splices, not on anything late-model.

03-11-2022, 11:22 AM
Etrailer probably has the same.

03-14-2022, 04:42 PM
My 2500 came with a bumper mount 7-blade.

When I had the gooseneck installed, they added a 7-blade to the inside of the bed. It simply provided a "T"/"Y" to allow the new end to go into the bed.

Look for the connector under the bed or tail lights