no harness modifications needed and bright white light from my LED Truck lights

 

Yeah the loyo ones I have, will as well, but its a lot less efficient and I do believe you've got diminished output as the lights have to rectify back to positive on the power lead.

 

Truck Lights are specifically designed with the housing and an LED bulb to perform well. They are not cheep, but they get rave reviews and outperform the halogen lights I replaced these with. They require less power then incandescent or halogen lights and they do not diminish over time nearly as much as halogen lights
I've wheeled with these for over 5 years and HIGHLY recommend them

 

Yeah, I think the point I'm trying to make here is that having to rectify negative to positive voltage inside the lamp is suboptimal, were as the old incandescents could care less.
Also the contact wear and tear on the switch is significantly reduces since you're only switching the low current relays on the new auxiliary headlight harness.

And if you go a bit further with the aux harness you can add DRL off your ASD relay with a diode to prevent back feeding for LEDs that have DRL and don't behave as expected

 

K Suspension instructions have a modification for that. I don't recall what is was off the top of my head but you should be able to find that info easily enough.

Todd