Any OBS trucks with the headlight relay mod?

[antiqueford]

I have purchased relays for the headlights and running lights, but the headlight wiring doesn't seem as small as on my '82. Do OBS trucks benefit from running heavier wire all the way to the bulb connectors? I will still put in the relays to take the load off the switch, but I'm not sure I need to replace the wiring. I guess I'll have to measure voltage drop at the headlight plugs...

 

['94IDITurbo7.3]

yes, put the bigger wire in.

 

[antiqueford]

^How did you accomplish getting the wires all the way into the plug? And do you think there's room for 10 ga.?

 

['94IDITurbo7.3]

did you buy relays and make a custom kit?

 

[bobracing]

Mine was done without changing the light wires. This made a HUGE difference, definitely recommend it. This is the second truck (89 & 93) Chris has done this conversion on and both are working well. Mine, ummmm, about 3 days. The other conversion is going a year or so now.

 

[antiqueford]

You mean you just cut and spliced the relay in without adding any wires? or were heavier gauge wires spliced in within a couple inches of the sockets?

94idi, I just have relays and plugs, no special kit or anything.

 

['94IDITurbo7.3]

http://www.ford-trucks.com/article/idx/8/039/article/Whiter_Whites_Brighter_Brights.html

 

[antiqueford]

That's the how-to I plan on following. I'm looking for information that isn't contained there. I think I've mentally prepared myself to dive in though.

The weatherproof bushing on the back of the headlight bulb connector can be drilled or punched through with a heated chunk of stiff wire to make 10ga wire fit through, the terminals themselves should be easy enough to solder to

 

[bobracing]

Believe he just spliced the relays in. Ran a new feed from the battery to the relays. The wires "should" take the power because they should have be sized from the factory for that much power.

Power from the battery, green hot, blueish grounded.

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The little metal panel was already there, not sure if stock or not:

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Hopefully the picture might help a little.

Edit: forgot to add.
This truck was an auto and the the engine bay wiring harness was pulled from a Diesel, so the engine harness was laying on the floor for him to do the mods.

 

[linkman440]

I went onto eBay and bought adapters so I can just plug into the factory harness .wire the relay into that and then another adapter form the relay to bulb. Works like a charm and no splicing of the factory wires

 

[antiqueford]

Making progress!
I decided to go with 12ga instead of 10.
You know its warm outside when flux is already half melted, and heatshrink shrinks itself.

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[antiqueford]

Its looking promising! Wired it temporarily to test and here's the results (engine off):

vBat: 12.16
Driver High Beam: 12.12v
Original High Beam: 11.4v

Here's the modded headlight connector:

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[War Wagon]

I bought a kit from LMC truck. Like $29 if I remember. I modified it a little. Added fuses and siliconed the back of the connectors. It plugged into the factory harness and does not modify the factory wiring. I thought it was easiest way to go. Works good for me.

 

[antiqueford]

And done!

Fuse box and relays:

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Drivers side:

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Passenger side:

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The loose wire going out the bottom of the pic goes to ground

 

[cowman79]

I did mine on my 94. I just cut the relays in with a feed from the battery. I would say it made about a 15% difference.