Anybody using the LMC HD Headlight Harness?

[xmitsu10]

I've seen the posts regarding making your own harness and relays for the headlight circuit. But found this premade harness with relays at LMC http://www.lmctruck.com/icatalog/cb/0067.asp

Looking for comments on quality/ease of installation from anyone that is using the LMC harness. Also looking at their H4 headlights from LMC or GMCPauls. I am aware that many are not happy with LMC service/quality, but GMCPauls does not sell the harness/relay (not that I could find).



Mark

[Draggn66]

I'd be interested in the answer also. Here's a ttt for ya!

[53lowdown]

I just installed the one from LMC. It works great for me. It doesn't have instructions specific to our trucks, but it's easy enough to figure out and it basically just plugs right in.

1 Disconnect and remove the battery
2 Connect the two hot wires from the harness to the hot terminal on the fenderwell by the battery
3. connect two ground wires from the harness to the body by each headlight. The relays can be attached to the radiator support below/behind the battery
4 Remove the existing wire/plug going to the passenger side headlight and plug it in to the receiver plug on the new harness.
5. Plug the wires from the new harness into each headlight. Your original driver side headlight plug goes unused so you'll want to remove it or tape it up.
6. Replace/reconnect battery and test your lights.

I took my time and installed mine in about 1/2 hour because I was trying to hide the wires but it really shouldn't take that long. The new harness is covered with some ugly yellow wire cover. I replaced it with some black wire wrap and it looks/works great.

[byrd]

I just did this to my truck for $15, it was easy as pie, just follow the drawing/schematic posted on here in the FAQ's. The LMC one seems reasonably priced, but there will charge you at least $15-20 shipping for
I would really like to know how you can hook the LMC harness in with NO cutting or splicing.

I had to cut and splice mine to get the relays into the system, wasn't bad at all, just needed some but splices, two inline fuses, two ring lugs for the battery heat shrink, good crimping tool, and a heat gun/ hair dryer, and about 3 hours to get it all installed. I got everything needed at radio shack

[agronomya]

Is this the harness that also lets you convert to a one-wire alternator? I found one on either GMCPaul's or Classic Heartbeat (can't remember right now) that replaced the old headlight harness and converted you over to a one-wire alternator, which I am really interested in. I was gonna ask about it later but I saw this and was gonna see if it was the one being used by you guys.

AA

[ClassicRedneck05]

does this harnes make the lights brighter? or what?

[53lowdown]

Roads have been too messy here in Kansas to get out and try it out, so I don't know what difference it has made yet. Mine were flickering when driving and dimming at idle.

You definately CAN install the LMC harness in a 69 C10 with no cutting or splicing - I just did it. See my post above.

[Madbomber88]

I bought this as well and am just waiting for some time to put in. Seems relatively straight forward though.
Do I have to buy high discharge headlights as it says, or can I just us the regular ones and the harness will make them brighter?

[53lowdown]

I just used my existing regular headlights. They seem brighter in the shop, but haven't tested them out on the road yet.

[ClassicRedneck05]

im also wondering about them headlights shown in the link he posted to LMC has anyone used these are they better? better yet anyone used them with this HD Harness?

[mrein3]

I made my own harness.
You do NOT need to use special headlights to take advantage of this wiring harness.

What the harness does is use the headlight wiring in your truck to switch on a relay. This relay then takes current right off the battery and applies it to the headlight.

The brightness difference come from the fact that before the harness upgrade you had less then 11 volts at each headlight. AFTER the upgrade you have 12.5 or so.

The increase comes from the fact that the factory runs 12 volts through approximately 20 feet of 16 or so gage wire. The drop through all that wire is up to 2 volts. With the upgrade they are using full battery power and applying it directly to the light through larger wire minimizing the voltage drop.

If you have stock lights and stock wiring I would do the wiring upgrade first. Then if you still aren't happy I'd replace the stock lights with halogens. Personally I don't see the value in the HID lights listed on the same page in the LMC link. They cost more. If you break the outside part of the light you need to cough up another $30 - PLUS SHIPPING.
With a halogen from Wal*Mart, if it burns out or breaks, you can just get another one for $7-$10 at ANY autoparts store.

[sleepyboy]

I bought my relay setup from Summit; made a BIG difference