This thread is meant to show how I set up my '77 F250 to tow a trailer. I'm sure there is more than one way to skin this cat and am open to any suggestions to do it better. I will post a separate thread for the mechanical portion of the project. Just comment if you have any questions and I'll try to answer as best I can.

I started with a place to mount the trailer plug and drill a couple of pilot holes before finishing with self-tapping screws:



Two hot wires were run from the battery side of my solenoid starter switch. One provides 12VDC to the electric brake controller and the other to the trailer plug. A auto-reset 30amp circuit breaker was put in between the brake controller and the battery (under the dash).



For the backup lights, I used an existing spice when I previously repaired my truck backup lights (using two wires from a brake light terminal):



The inline plug works great and was a breeze to install:



I followed the remainder of the directions to wire up the electric brake controller and plug terminal, and ran a transmission line temperature gauge:

 

That looks nice... pretty much how I did mine and it works fine. I do have a suggestion or two. In the rear, where the grounds mount, it would be good idea to clean the frame. A light touch with a die grinder or sander, around the bolt hole. Then remount the grounds with a little grease on the frame and in the hole. Touch up the frame paint as needed. That will help keep a good ground for a long time and make it a lot easier to remove someday when needed.

Also, did you also put a breaker for the auxiliary power going back to the trailer plug?

And now the fun part... what will you be towing?

 

I hit all the ground spots with a small dremmel tool until the metal shines, even when I am re-using the spot as in this project - that's a great point B&W. Yes, I need to POR-15 my entire tow mount. I did not put a breaker in the aux power to the trailer, as the diagram didn't call for one; did you install one on this wire?

We bought a 2014 18'-ish trailer in pretty good shape. It's our first trailer (I'm still a tent camper, but my wife wanted the upgrade).

Although I'm not worried about it overheating with the modifications that I made, I do need to troubleshoot why the trans temp gauge is sitting like nothing is hooked up to it. It was pretty simple to install: one 12VDC wire, one ground wire and one wire from the sender. I checked the firmness of the soft lines and they were firm (with pressurized fluid); more so on the "cold" side interestingly...

 

Looks good for light duty and occasional towing.

But since you asked...if you really want to go all out, you want dual batteries, a smart solenoid, #4 wire, mega fuses and Anderson plugs.

Dual Battery Systems | Alternator charging, how it should be done

https://www.ford-trucks.com/forums/1...-the-77-a.html

 

Nice trailer... looks like you will have some fun. For the auxiliary power feed - or basically anything connected to the battery - a breaker or fuse is a good idea. In case of "oops" like pinched wire or short circuit in the trailer you need a fuse or breaker so to prevent major melt down or fire.

 

Had to jackknife trailer once do to deep water and chopped the 7 wire off the trailer. Probably only took a second to do but that power wire fried before it blew the fuse in the truck. Camper didn't have a fuse until clear back at the inverter box. Make sure the RV has a fuse at the battery too.

 

For the non functioning temp sender...

It looks like the "T" the sender goes into is electrically isolated by rubber hose all around. It needs to be grounded for the gauge to work. As diagnostic, try clipping a wire clamp on the T and connect to ground.

I had to ground a remote oil pressure sensor that way once... I soldered the ground wire to the brass T.

 

Thanks all for your advice and this is my first foray into a trailer / towing with an older vehicle. Our Powerstroke Excursion came from the factory with all of the goodies installed already (as far as I knew). I will try out the temp sensor ground and can pull off a hose to install an "O" connector ground wire pinched in between the hose and the brass nipple if I need another ground.

 

I've ridden in a few Excursions and they are nice vehicles. That said, I like your current tow vehicle better. Dents are great at this and glad to see one well used.

 

Now we have a zero ohm connection between the sending unit and grounded radiator. Not the prettiest, but very functional. Tomorrow we hook up the trailer and see how everything works (i.e. "two dollar bets...")