Forum Discussion

waterman7474's avatar
waterman7474
Explorer
May 11, 2016

Hooking up lights for a tandem double tow

I have an 18ft trailer that has a full hitch set up on the back (yes, its all properly welded/bolted to the frame and a "real" bumper) and I am going to double tow a small 8ft utility trailer with my smoker/pit on it to an event.

The question I have is, what is the best way to run lights to the smaller trailer?? The big trailer has the larger round connector and the smaller one has the little flat 5(?)-pin. Thinking it would be easy, I just ordered a 30ft 5-pin extension and was going to just run that also (nice and tidy) under the big trailer to the smaller.

BUT....my truck has the newer common attachment for both and like most, they are covered by little dust doors and you can't open both at the same time.

What is the best way to do this???

Short if taking the little dust covers off the attachment points on the bumper (if I can with out breaking them), I'm at a loss.

Thanks
  • Bedlam's avatar
    Bedlam
    Moderator
    May 11, 2016
    I helped my friend with his. I used the head end of a finishing nail as a punch. Clamp the nail into vise grips and tap out the hinge with a rubber mallet.
  • waterman7474's avatar
    waterman7474
    Explorer
    May 11, 2016
    Thanks all.

    I would really like to avoid splicing into the existing wiring and opening up the possibility for future failure.

    I will try to pull the pin on the dust covers.
  • carringb's avatar
    carringb
    Explorer
    May 11, 2016
    I simply spliced into my travel trailer's wiring looms at the rear corner, where they run from the sub-floor into the wall. I pulled the taillights to help locate the best location to cut the plastic stuff underneath. I used a flat pigtail with LED test-lights built-in, so if the 2nd trailer lights don't work I know its the 2nd trailer, and not in my modified wiring. My travel trailer used 14-gauge wiring, but was upgraded to LED lights, so I know it'll carry enough current for a 2nd trailer.
  • C_B_'s avatar
    C_B_
    Explorer
    May 11, 2016
    Just tie into the wires on the back of your 18' trailer with a 4 pin connector.

    That's what I did on my 5er.



    So as not to overload the wiring on the 5er I used led lights on the 4' X 6' that I pull behind.




    C.B.
  • Grit_dog's avatar
    Grit_dog
    Navigator
    May 11, 2016
    Bedlam wrote:
    The hinge pin can be pushed out of the dust covers to remove them. To keep the connector clean when not in use, use a dummy plug in the 4-pin side.

    ^This or make/buy a splitter with a long whip to the rear trailer.
    Or if accessible and you're going to be doing this many times, tap into the rear lights in the front trailer and make a dedicated plug on it for the tandem.
  • discovery4us's avatar
    discovery4us
    Explorer
    May 11, 2016
    I wired a four pin plug into the taillights of my FW and then plugged the second trailer to it. Never had an issue. Only down side is no brakes with a four pin plug unless they are surge brakes.
  • nevadanick's avatar
    nevadanick
    Explorer
    May 11, 2016
    I have done it both ways. On my Ford i could plug both into the truck but my Dodge i had to tap into the travel trailer. Pretty easy to setup either way.
  • Bedlam's avatar
    Bedlam
    Moderator
    May 11, 2016
    The hinge pin can be pushed out of the dust covers to remove them. To keep the connector clean when not in use, use a dummy plug in the 4-pin side.

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