Hey all, I just got my trucks and under the hood on the 86 with the 302 FI there's this rheostat looking device on the driver side wheel arch. Has anyone seen this before and know what it's for?

 

Yep have seen one before and I know what it is






Old school electric trailer brake load adjuster.
The old controllers worked off 1 of the brake lines and there was no to adjust how much power went to the trailer brakes when loaded or un-loaded.
Loaded was not much of an issue but un-loaded and the brakes would lock up.
Guess it could do it loaded too?

You undo that screw and slide the "bar" up or down to check the resistance or power sent to the trailer.
Bar closer to the wires more power to trailer, farther from wires less power to trailer.

Is there a controller installed in the cab under the dash?
If not but the wiring is out back you can run the output wire to one of the wires on that part that goes to the rear and leave the unit there as it is not hurting anything.
BTW new controllers dont hook to the brake line and all the adjustments are on the under dash unit.
There are 2 different types of controllers today, timed and proporsinal (sp?) dont go with the timed type.
Dave ----

 

If you still have all the parts I would try to keep it. They worked pretty good, much like the fancy tow/haul stuff on the late model trucks. The more pressure you have on the truck brakes, the more electric you send to the trailer brakes.

 

**EDIT**

I can see this is going to happen from time to time.... I confused the 2 trucks I have. The truck that this Trailer Brake control device is in DOES have the controller under the dash...
I honestly don't remember seeing anything under the dash when I was under it trying to find the release button for the headlight switch. I'll look again when I'm working on it tomorrow. Tomorrow I plan to work on pulling the starter and try to get it working again so that I can get the truck running. I know starters are relatively cheap but I don't want to put much money into a motor that I plan to sell off in the next couple of weeks. As long as I can get a video of the motor running I should be able to sell it easily.