What is this?

[Jagg82]

I am new with this truck and seeing things I have no idea what they are. I would think at my age I would have seen everything but guess not.
Its on drivers side sitting under hood on fender well. The wires have been cut to it so not sure what hooks to it. Any Ideas?
1985 Ford F250 6.9 Diesel 4X4.

 

[myrl883]

It's a resistor for an old aftermarket trailer brake controller. In the days before electronic controls, those were used to control current to the trailer's brakes.

[Gary Lewis]

My first thought was a spring delay for an audio system.  I had one in my '58 Impala and it made neat, strange sounds.

But, I don't think that's what that is.  It looks more like a heating element.  And since you have a diesel I'll guess it was to heat the fuel lines.  But I don't think it is factory.

[Jagg82]

Very Cool! I kept looking for wires that may have gone to it and did find a couple with old style connectors but was not able to trace them  

These old trucks are so cool! Thank You

[Gary Lewis]

myrl883 wrote

It's a resistor for an old aftermarket trailer brake controller. In the days before electronic controls, those were used to control current to the trailer's brakes.

Learn something every day!  (And, with my memory, it might be what I learned yesterday.  )

[1986F150Six]

Gary Lewis wrote

My first thought was a spring delay for an audio system.  I had one in my '58 Impala and it made neat, strange sounds.

Reverberator?

[Gary Lewis]

Yes, reverb - short for reverberator.  It worked, but sounded weird on hard bumps.  

[FuzzFace2]

myrl883 wrote

It's a resistor for an old aftermarket trailer brake controller. In the days before electronic controls, those were used to control current to the trailer's brakes.

Yep that's what it is.
When I was a kid our tow car(s) had them for the trailer brakes.
The controllers hooked into the brake line to apply the electric brakes and no way to "dial it back".

If the trailer was empty you would slide the bar to the end away from the wires, less power to the trailer brakes.
Then loaded you would slide it back to the wires, more power to the trailer brakes.

The new electronic controllers you don't need this resister, it is all on the controller.
Dave ----

[85lebaront2]

I guess I am lucky, my hydraulically actuated Kelsey-Hayes controller is adjustable for voltage so I can "tweak" it while driving.

[FuzzFace2]

85lebaront2 wrote

I guess I am lucky, my hydraulically actuated Kelsey-Hayes controller is adjustable for voltage so I can "tweak" it while driving.

IIRC they only adjusted how much pressure on the pedal was needed before the controller would move.
Now if you found at 1/4 movement the trailer was locking up when empty you could adjust the resister under the hood.
Now load the trailer and move it back and you were good.

Now I don't ever remember it being adjusted with the camp trailer as it was loaded all the time.
On my Dodge with my car trailer and the newer type controller I also have not needed to adjust it loaded or not?
Dave ----

[85lebaront2]

It actually changes how much of the flexible contact goes against the resistor. I didn't take any pictures of it opened up but it has worked well for me on my 1977 F150 and Darth, not too shabby for something I paid $60 for years ago.

[FuzzFace2]

Yep they worked great till ABS came out and the 2 did not play nice together.
Dave ----