Updated headlamp harness

Did you make a harness or purchase a pre-built harness

  • purchase pre-built

    Votes: 4 66.7%
  • made your own

    Votes: 2 33.3%

  • Total voters
    6

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Jeff Simon

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1984
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Silverado K10
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5.7l V8
I recently got new LED head lamps for my 1984 K10. The new lights have a three prong connector. I want to run both top and bottom with high and low beams. I'm wondering if anyone has converted to LEDs and have updated their harness. If so, did you create your harness or did you purchase a prebuilt one? If you created one what size relays did you use?
 

donnieray

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350,355;350.
Hello and welcome to GMSB. The relay kits are what I'm thinking you are referring too and they are a popular upgrade and definitely supply more voltage to the lamps. I purchased mine but later replaced the relays with better units. They wouldn't be hard to make if you have the relays and bases and correct sta-cons.
 

75gmck25

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I used the prebuilt kit from LMC truck, and its been working fine for the last few years.

The kit came with very bright colored wiring (yellow?), so I ran it through convoluted black tubing that matched the rest of the engine compartment tubing. I mounted the relays near the battery and run the lighting power directly from a power junction connected to the battery positive.

Bruce
 

73c20jim

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I want to run both top and bottom with high and low beams.

You want to run the high beams and the low beams both on always together???
 

1985c20

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You want to run the high beams and the low beams both on always together???

I think he wants to have all 4 headlights on with the low beams. Factory only 2 of the headlights were dual beam and 2 of them were high beam only. To the OP because of this modification you will probably have to make your own harness, however with LED bulbs it’s probably not necessary to run a relay harness. They draw so much less power compared to halogens. If I were you I would just buy 2 sockets that fit and splice them in so you have all 4 headlights on both low and high beam. However you might want to check local laws about how much light you can legally have on low beams so cops don’t harass you
 

73c20jim

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I think he wants to have all 4 headlights on with the low beams. Factory only 2 of the headlights were dual beam and 2 of them were high beam only. To the OP because of this modification you will probably have to make your own harness, however with LED bulbs it’s probably not necessary to run a relay harness. They draw so much less power compared to halogens. If I were you I would just buy 2 sockets that fit and splice them in so you have all 4 headlights on both low and high beam. However you might want to check local laws about how much light you can legally have on low beams so cops don’t harass you

I guess I misunderstood, having only two round headlights.
 

Rob Goblin

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Rob
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1984
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C10
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350
I used the prebuilt kit from LMC truck, Bruce

I was unaware that LMC sold these (I guess I have been to busy with trying to get everything right with the body and interior). I’ll definitely be checking into these since everyone blinds me at night with these new cars. I still can’t believe that is legal.
 

Crispy

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Harnesses are so cheap nowadays that buying a generic prebuilt one on ebay or amazon will be under $10. Depends on if the cost is worth your time. Also depends if you can source just enough material needed for the project. Chances are you will spend more than $10 on 2-3 relays, a short spool of wire (multiple spools if you want to color code wires) and connectors but you will have for future projects.

I bought bulk quantities of everything and have it handy in the shop.

Also note, the generic premade harnesses are sometimes too short for a tucked appearance. LMC harness is nice, and it works well. My Burb came with one installed but i removed it and sold it. Custom made one for the HID setup. The LMC harness also uses a different style relay so replacement (if needed) would mean you have to wait for a part to arrive by mail.
 

radio2000

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I recently got new LED head lamps for my 1984 K10. The new lights have a three prong connector. I want to run both top and bottom with high and low beams. I'm wondering if anyone has converted to LEDs and have updated their harness. If so, did you create your harness or did you purchase a prebuilt one? If you created one what size relays did you use?
Which LEDs did you go with?

Sent from my SM-G955U1 using Tapatalk
 

donnieray

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86 C10, 84 K10 MM7 NP833 option truck, 85 K10.
Engine Size
350,355;350.
I used the prebuilt kit from LMC truck, and its been working fine for the last few years.

The kit came with very bright colored wiring (yellow?), so I ran it through convoluted black tubing that matched the rest of the engine compartment tubing. I mounted the relays near the battery and run the lighting power directly from a power junction connected to the battery positive.

Bruce
Yep, the LMC kit. After a couple years I lost high beams in two trucks and replaced the relays with better units and haven't had a problem since.
 

Jeff Simon

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Jeff
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1984
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Silverado K10
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5.7l V8
I think he wants to have all 4 headlights on with the low beams. Factory only 2 of the headlights were dual beam and 2 of them were high beam only. To the OP because of this modification you will probably have to make your own harness, however with LED bulbs it’s probably not necessary to run a relay harness. They draw so much less power compared to halogens. If I were you I would just buy 2 sockets that fit and splice them in so you have all 4 headlights on both low and high beam. However you might want to check local laws about how much light you can legally have on low beams so cops don’t harass you
local law for me allows a vehicle to run 4 lights up front.
 

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