with Bill Johnston
Flat Towing Hookups
We all love to trail ride, but do we all drive our trail rigs to the trail? Not always. Some folks use trailers, some use car dollies and others flat tow their rigs. For those that flat tow, one of the biggest problems is setting up a lighting system that is safe, legal and easy to stow when not in use. We are going to take a look at one option that requires no changes to the existing electrical system and when installed only needs a small, removable umbilical cord.
When flat towing, the vehicle basically becomes a trailer, so you only have to have lighting out back (like a trailer). A standard 4 wire trailer lighting kit can do the job. but depending on your needs and state laws, you can make it more complex with additional wires. Many states require an additional braking system on vehicles/trailers of over 2-3000 lbs. Check your local laws for exact figures. Wire bundles of six or seven wires can be used to allow for a braking system or onboard power. In this installation we will be using a six wire bundle set up like the diagram below. Not only does it have the four wires required for standard lighting, but it also has the power and control wires that can take care of many of the auxiliary brakes systems out on the market. The six wire round plug is a common plug found at most auto parts stores. We start at the front bumper where the connection to the tow vehicle is. A protected connector plug is a good alternative to coiling the cable up under the hood. There is nothing to fall out and get caught under a tire while on the trail. The cable between the vehicles can be removed and stored in the tow vehicle for safekeeping.
For those interested in the tow bar arrangement, it is a Reese tow bar attached to a set of Currie CJ Tow Shackles.
Removing the bulb assemblies from the trailer lighting kit will net you a nice pair of three-way bulbs. Three-way? Yup, they will serve as you tail light (parking light), brake light and turn signals. There is plenty of room inside the stock housing to add the bulbs as shown. Run the wires along the frame to the front bumper, just like a trailer. Take a look at the diagram to the left to give you an idea as to how the wires are traditionally run for a single bulb (left and right). You could probably go a little farther and add small bulbs to the side marker lights on the ends of the rear bumper. These could be tied into the tail light (brown) wire. The wires that are not shown are the brake actuator (blue) wire and the aux power (black) wire. They would run into the cab. I use this setup to tow my little Zook behind the motor coach when out on trips. Although this setup is shown here on my daily driver/stocker, it can easily be done on a trail rig. Aftermarket lighting may be a little harder to adapt, but use your imagination and anything is possible.