ID this part?
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Junior User
Joined: Mar 2017
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From: Tualatin OR
Any idea why it would be on the side with the secondary battery or did it use both batteries to start and the second would become a auxillary battery after?
Cargo Master
Joined: Jul 2015
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From: tucson
That looks like a Kelsey-Hayes resistor for their trailer brake controller. You would hook up the output wire to better tune the trailer brake response.
Do an ebay search for kelsey-hayes selective resistor.
john
Do an ebay search for kelsey-hayes selective resistor.
john
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FTE Legend
Joined: Sep 2003
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From: NY and VA
Ditto on brake controler.. Do believe a resistor wire cut the voltage down to the coil.Not a stand alone resistor like the Chevs and Mopars had.
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Fleet Owner
Joined: Jan 2004
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From: Brentwood,CA
That's the notoriously unreliable Kelsey hayes resistor which is for trailer brakes and goes to a equally terrible hydraulic brake controller. Ditch the whole disaster before it sets the truck on fire or decides to spray you in the cab with brake fluid.
Ford Parts Specialist
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From: Simi Valley, CA
or did it use both batteries to start and the second would become a auxiliary battery after?
FTE Legend
Joined: Sep 2003
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From: NY and VA
Back in the 1970's truck campers were popular. Many times an auxiliary battery would be installed to run the camper's electricity (with a switching device so as not to run the truck's battery down.)
FTE Legend
Joined: Nov 2015
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From: Angier, NC
That is what you ran before ABS came out on cars & trucks and this would not work as it should.
There should be an adjuster part that run between the 2 long spring parts with a thumb screw to slid up & down to change resistance based on trailer loaded weight.
Most of my trailers were loaded be it car or TT and most of the time pulled by the same car or truck so I had no need to adjust this resister.
Dave ----
Cargo Master
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From: tucson
There are two types of Kelsey Hayes resistors that are commonly found. On the type you have the leads are attatched at different points to adjust resistance. The other type ( I have one), has a reisister coil in a U shape with a sliding bar on it for adjustment.
Warner and Teconsha offered similar brake controlers and NOS condition ones sell quickly.
Warner and Teconsha offered similar brake controlers and NOS condition ones sell quickly.
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