GMT400 projector retrofitting

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88GMCtruck

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Really good info.

I recently did a budget minded projector retrofit as well. I picked the headlights up at the junkyard (diamond clear housings) and wasn't scared to destroy them. The projectors are Morimoto Matchbox H1s - they are the smallest bi-xenon projector they have. I paired them with 35watt H1 HIDs from amazon.

So in order to fit them in the headlight all I had to do was concave the area right at the bulb a little bit to gain like, 2mm of clearance, and trim the top of the shroud. That is it. It was basically a bolt in affair.

Now I will say after having them awhile, they are OK. They aren't as bright as I'd like (although 55w HIDs might work better) but they have a good cut-off line and aren't offensive.
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RokRoland

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I really dig the write up. Ever since day one my 1989 has had really poor low beams. High beam is fine.

However in order to successfully do any of these mods I really need projectors that are DOT approved, not just "exceeding DOT specifications". Any pointers to such would be really helpful. I guess I could also try to throw in a sealed beam LED unit to replace the low beam but I am not convinced of the quality of these units at reasonable budgets.
 
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Still haven't finished this thread, got busy at work and haven't been on the forum much. Planning on finishing the write-up over the next few days though. Sorry for the delay for those who wanted to know more details.


Any update on that write up?
 

df2x4

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Glad you guys came to a civil conclusion here.

I tend to agree with the "why" sentiment. IMO you can get plenty of light output simply by upgrading the headlight harness, housings, doing the 4-Hi mod and running good bulbs with no blue on the glass.

However, if someone feels the need to put HIDs in one of these trucks, this is 100% the only acceptable way to do it as far as I'm concerned. As long as this thread prevents one person out there from throwing HIDs or LEDs into the factory housings with no other modifications, I'm OK with it.
 

deejaaa

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what name calling? guess i skipped over it.
i personally don't like the "look" of HID's on a GMT400. the style looks out of place. especially the angel eyes. might as well run 22s and stick on chrome.
 

Brother Al

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My own $1.00 contribution to this...
And take it or leave it, its free and a worthwhile reading if you arent exactly independently wealthy.

These mods clearly remove any DOT-compliance the original headlights had. Doing this opens the door to partial or total liability, if you are involved in any kind of dusk-to-dawn accident, especially if there are personal injury claims, or if, God Forbid, death is involved.... I personally would preface this entire thread with "For Off-Road Use Only", &/or "Use at Own Risk".

Why?
I can guarentee that any accident investigation will outline every last safety issue found... EVERY deviation from what is required under Federal and State law will be focused on, especially if "State Police" become involved with the accident scene reconstruction... Insurance Companies can also inspect the vehicle, after the police are finished. Their investigators will look for anything, any reason to drop the hammer on you, especially your own ins company, if it appears you may be at fault.

Having "improved" lighting by using off the shelf DOT-Compliant Lenses & DOT-Compliant Bulbs is one thing. Taking those components and cutting holes in the DOT-Compliant part's reflective lens is another entirely... You see, once you structurally change the housing &/or lens assembly, it deviates significantly from its original design... which originally met the Manufacture's required NHTSA/DOT Compliance mandate. And although manufacturers are required to "self-test" their own lights to meet "DOT Compliance" standards, they also need to back their self-certification with verifiable test data, otherwise they would be blatantly liable and the lawyers would line up to sue. You also have to contend with various state laws that add to the Federal requirements.

More:
"Federal Motor Vehicle Safety Standard 108" (FMVSS-108)
AKA "Section 571.108 - Standard No. 108; Lamps, reflective devices, and associated equipment."
https://www.gpo.gov/fdsys/pkg/CFR-2004-title49-vol5/xml/CFR-2004-title49-vol5-sec571-108.xml

And:

"Motor Vehicle Safety Title 49, United States Code, Chapter 301 and Related Uncodified Provisions Administered by the National Highway Traffic Safety Administration, Department of Transportation (NHTSA)"
PDF: https://www.nhtsa.gov/staticfiles/laws_regs/pdf/MVS01092008

Of particular note is "49 U.S.C. 30122"

"if equipment is installed by a manufacturer, distributor, dealer or motor vehicle repair business, that equipment, as installed, must not make inoperative any of the required safety equipment.
If an item of equipment impairs the effectiveness of the lighting equipment required by FMVSS-108, we consider the installation of such equipment to have rendered the lighting systems partially inoperative."


I can whole-heartedly say that, in the event of a serious accident that involves this modified headlight set-up, pretty much every body will declare that the modification outlined in this thread violates the law and the lowest common denominator will be blamed...

"Impairs Effectiveness" can and will be readily defined to suit the needs of the lawyers prosecuting you, whether civilly or criminally. In court, you cannot "claim" any modification enhances safety, unless you can prove it with formal scientific verification and a certified professional/expert witness. Simple testimony, pictures, and videos will not suffice any arguement in court, so without that info, you are sunk, no matter how good they actually may be.
 
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