Aftermarket Replacement Lamps, Mounting Questions

John_Galt

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So there is a slew of information on retrofitting existing headlamps with projectors or bulbs of one sort or another, all across the web. As has been repetitively pointed out here, such a modification to an existing and compliant lamp is illegal (reasonably so).

But what about mounting lamps of a completely different format on a vehicle? Not as auxiliary lighting, but as a full on replacement for, say, an oem lamp that was poor performing when new, and that is not in one of several standardized formats (e.g. 5-3/4" or 7" round, 4x6" or 5x7") that has a variety of possible lamps that will funtion as a legitimate upgrade over the lamp it replaces.

To put it simply, is it legal to remove an OEM headlamp housing and possibly the underlying mount/mounting hardware in order to replace it with a solidly mounted bracket for say a 5-3/4" or 7" bucket that allows for horizontal and vertical adjustment of aim?

My curiosity was piqued recently. I drive an older vehicle (3rd gen 4runner) and despite a relay harness, good bulbs and recently cleaning the housings, is beginning to leave me desiring more light. A common thing on t4r.org is one of several highly touted LED headlight bulbs (not legal, install threads clearly illustrate massive increases in glare, very blue light produced, and the common complaint is of a noticeably decreased viewing distance [so not much of an upgrade, eh?] or a projector retrofit of some type or another. Not an option for me. I also already run a set of cibie led auxiliary high beams, so adding a set of auxiliary lamps seems to be a step back (being that high beams here in the US are constrained to 75k candela output), and you certainly will attract unwanted attention having 4 uncovered auxiliary lamps on the front of a behicle, let alone 6 illuminated lamps.

In my case, my 4runners headlamps are a headlamp only lamp, large in size both vertically and horizontally, and have a deep mounting depth, that also uses spaces in the core support to accommodate their depth. The lamps also sit in a bracket that has several solid mounting holes in the core support. Frankly, it would not be a problem to create a mount for a 7" bucket that would place the lamp in approximately the same space (and still well within the min/max mounting heights and widths), that would attach solidly to the core support without modifying it. Some sort of bezel would likely be needed to fill in the resulting gap, but I have no issues working with fiberglass and molds.

So, is it legal to fully replace an OEM lamp and mount with a diy one that allows for both vertical and horizontal beam adjustment?
 

-Virgil-

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Legally, there's nothing stopping you from removing the original headlamps and installing some other kind of headlamp that meets your local requirements. There's no Federal or state-level rule that says cars have to have the original-equipment type of headlamp. So you could (for example) put in any of these, ditch the sealed beams and put in these or these. You'd have to make sure to mount the new mounts plumb and true so you can achieve correct vertical and horizontal aim. And they'd look kind of hacked-in unless you fabricate some kind of a trim plate, but don't put a cover, even a "clear" one over them -- that is illegal (and for good reason).

If the truck-type mounts don't float your boat, you can use mounts from a junked vehicle or buy new OE parts. The list of parts you'd need for the large (200 x 142 mm) mounts is
2x this
2x this
1x this (pic sometimes displays incorrectly but part is correct)
1x this (that's what the one above looks like, except for the other side)
2x this
2x this
4x this

(But the stock factory headlamps on a Gen3 4Runner, if they're in good condition and fitted with good bulbs, are actually pretty good...)
 
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Lynx_Arc

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I doubt I will ever buy these lights...... but one question anyway, Are these plastic lenses going to one day turn yellow like most other plastic lens auto light assemblies out there?
 

Alaric Darconville

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I doubt I will ever buy these lights...... but one question anyway, Are these plastic lenses going to one day turn yellow like most other plastic lens auto light assemblies out there?
"Most"? All. Yes, they will. Some will last a little longer than others but it's still plastic. And don't forget for the halogen options that the reflectors themselves will degrade over usage and time.
 

-Virgil-

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Assuming good quality materials and good quality construction (i.e. a reputable brand), the polycarbonate lens in front of the LED headlamp is going to last longer than the polycarbonate lens in front of a halogen or xenon headlamp. This is because the LED lens will run much cooler (even with a lens heater), and operating temperature is a major factor in how fast and how severely the lens and its coating will deteriorate in response to UV. Also most of the reputable-brand LED headlamps in standard sealed beam sizes are intended for heavy-duty usage on commercial vehicles, so their lenses are made of higher-grade polycarbonate and coated with higher-grade coatings compared to light duty passenger car lamps.
 

Lynx_Arc

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Too bad they didn't see fit to use glass lenses it would be worth the money as the LEDs should last a lifetime
 

Alaric Darconville

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Too bad they didn't see fit to use glass lenses it would be worth the money as the LEDs should last a lifetime

No automotive part really "lasts a lifetime". We replace not just the brake pads, but rotors and calipers. Clutch master cylinders, clutch slave cylinders, valve cover gaskets, PCV valves, door lock actuators, upholstery, the list goes on. Sure, it would be nice to use glass lenses but there are things like coefficients of thermal expansion that must be dealt with when sealing the lens to the rest of the lamp. The LEDs will last a long time, but even they will degrade and can have accelerated degradation depending on the conditions they experience.
And they always run the risk of getting in a collision or rocks flying and things like that. There's only so much engineering they need to put into a product to get the job done and last quite a while.
 
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