Towing your Tumbleweed Trailer with a U-haul Pick Up Truck

As you may have gathered by now, Sam and I chose to pick up our trailer and SIPs ourselves and tow them home by renting a U-haul pick up truck. In the end, this worked out rather well for us, but there were a few things we had to trouble shoot along the way. Here's the rundown.

First of all, the U-haul pick up truck come with what's called a 4-Pin electrical fitting. It's located under the back bumper near the trailer hitch and looks like this:



Open up the rubber cap, and you'll see this:



Be sure to check this out before you leave the U-haul dealership, we didn't and found that ours had a lot of dirt and corrosion in there, despite the fact that it was a fairly new vehicle (only 6k miles on it when we picked it up). We had to do some significant cleaning before we could use it.

Now, if you're buying a Tumbleweed trailer like we were, your trailer will have what's called a 7 Blade electrical hookup, which looks like this:





So, you'll need an adapter to connect the two. It's very important that you get a "4-Pin to 7-Blade" adapter and not the reverse. Make sure that your adapter specifies that it goes from a 4-Pin Tow Vehicle to a 7-Blade Trailer. There are many adapters out there which will attach a 7-Blade vehicle to a 4-Pin trailer, but we could only find one adapter that would connect a 4-Pin truck to a 7-Blade trailer. Sean at the trailer dealership told us that there's really only one on the market and that it can be hard to find, so I guess we were lucky- point is, just make sure you get the adapter you need.

Most of the wires coming out of the adapter are there to attach the adapter to your truck's trailer braking system. Unfortunately, U-haul trucks aren't wired for trailer brakes, so we tucked these wires up out of the way.



There is, however, one wire that you need to do something with, and that's the white ground wire. This will need to be attached to the metal frame of your tow vehicle. This was accomplished for us through no small effort by a good samaritan, with the use of a self tapping screw and a couple of washers (because even when he pushed on his impact driver hard enough to lift the truck off the suspension, he still couldn't seat the screw tightly enough to get a good connection between the ground wires and the truck frame.  The washers helped fill that gap).



Once the wires are sorted out, you fit the 4-Pin portion of the adapter to the 4-Pin portion of the truck, and secure the 7-Blade portion of the adapter facing out. Usually, you'd secure the adapter by screwing the included mounting bracket into your truck, but as this is a rental and we don't want to be charged penalty fees for damaging the thing, we went a slightly different route, and made use of a good quality duct tape:

And you're off! Be sure to check your lights at ever rest stop you come to. Don't skimp on safety checks: check left blinker, right blinker, brake lights and running lights each time. You may have to pull off all your duct tape, reseat the 4-Pin portion of the adapter, and then duct tape the whole this up again. (You may have to do this several times). It's worth it. Drive safely!