I just replaced the headlamps in my 84 F250 with ones that have H4 bulbs. They look kinda dim to me, do I need to do something with the wiring harness to get better brightness? Is there a harness that I could buy to do this? I like the look of these lights otherwise I would just put the old lights back in.

 

A lot of these gee wiz bang aftermarket lights are not even DOT approved for road use. They bring them in from China and sell them all day long though. If you want brighter lights, they do make relay kits for this, it makes the stock lights noticeably brighter. You can't hardly buy the parts and the wire and do it yourself for the price of this kit. It's at the bottom of the page in this link.

Truck Parts and Truck Accessories

 

Thank you. Yes, these were some cheap lights and I'm not sure the wiring upgrade would help them. I think I'll just put the old lights back in and call this a little failed experiment.

 

The relay kit in the link provided by Franklin2 works quite well. I purchased two and installed in my 1986 F150 and my son's 1984 F150. We have been using them for 5+ years with no issues. Although I have not needed a replacement, I would recommend the purchase of an extra relay, since they are different from the readily available Bosch style.

I am going from a faded memory, but I believe the voltage [before] at the headlight was ~11 volts and increased to ~12.5+ volts [after]. It made a marked improvement.

 

You would have to go with a name brand such as Hella, they are who makes headlights for BMWs and Mercedes. I got a set on my truck from them they are real glass which is a plus you don't have to worry about hazing like plastic. The ones I got are also ECE approved not DOT approved but they seem to work good with the H4 bulbs.

The relay kit is a must have as well. Even if it doesn't brighten your lights it will at least take the load off your headlight switch making it last longer.

 

I used the rampage brand conversion from bronco graveyard, and their HD harness. The harness moves the load off the headlight switch and on to a pair of relays. I recommend the harness for EVERY bullnose truck because the switch can catch fire in its factory configuration. Take the load off the switch, and it doesn't heat up and melt and burn.

The light housings themselves are metal with a glass lense that says it's DOT approved. They were provided with Phillips brand bulbs. They were made in Taiwan. They are quite bright, and a vast improvement over stock.



I had quite a discussion elsewhere about headlights. It can be a very heated discussion. Only those made in America or the EU are going to be truly DOT approved. Others might be, but you can't trust what China prints on a box or part. Many will throw light in funky patterns and may blind oncoming traffic. Hella and Cibbie are the two top trusted replacement brands.

 

Yep but you have to be careful with Hella they sell DOT approved and ECE approved. I got the ECE one as they have a sharp cut off line and put the light on the road where it is wanted. Down side is its not DOT approved. Basically its not street legal in north America and mexico but it is legal every where else in the world. But I haven't had a state inspector fail my truck for it as they don't check for stuff like that, they just check functionality.

 

You guys have convinced me to get the wiring harness and install it. Don't need things catching on fire if I can help it.

 

Not hard to install. I got mine from ebay, just plug it into your existing headlight connector it uses that as a trigger for the relays. Then you hook battery voltage and ground and you are done.

 

I have the one from LMC ordered. I was looking at my existing wiring tonight and noticed that it has a four pin plug in. Hoping the new harness has the same, many of the pictures I looked at just had three pin plug ins.

Now that I look at it, the picture of the harness I ordered shows a three pin plug for hooking into the existing harness. How do I deal with that?

 

All sealed head lights I have seen only had 3 spades, high/low/ground.
Where are you seeing this 4 pin connector on your truck?

I also have 2 LMC relay kits, 2 different projects, and they are just like Rusty said - un-plug your head lights, plug the relay harness into your lights, the trucks head light plugs into the relay hardness, power & ground and you are set.
Son used 1 of my relay hardness on his YJ Jeep, other than where the power & ground is it worked.
Dave ----

 

I'm talking about where the relay harness plugs into the existing truck harness, not the headlights. The picture shows a three spade male plug. My truck has a four spade connection on the pass. side fender well that I assume is disconnected and the new harness is plugged in there so I can use the headlight switch to turn on/off, bright/dim. This is the connector I'm worried about.

 

Interesting, this 86 diagram does not show any connectors in the underhood area for the headlights.

Headlamps - Gary's Garagemahal (the Bullnose bible)

This 81 diagram doesn't show any either, just splices.

Lights: - Gary's Garagemahal (the Bullnose bible)

 

Can you post up a picture of this 4 spade connector on your truck?
The relay harness plugs in to the 1 of the 2 head light plugs you remove from the head lights.
The relay harness plugs into the head lights and the harness has a 3 spade male connectors that plug into 1 of the trucks head light female plugs you pulled off the head lights.
Again every head light I have seen has 3 wire plug or if you have a 4 light system the hi beam has a 2 wire plug.
From Ebay on a Google search

http://www.ebay.com/i/112046993532?chn=ps
Dave ----

 

OK, I get it now, the three spade plug goes into a headlight plug.
That makes sense.

Sorry, I was thinking it plugged into the wiring harness close to where I was going to mount the relays. Drrrr., nothin gets by me does it?!?!