Tech: 88-89 GMT400 Quad Sealed Beam upgrades (Bosch T84 E-code headlights)

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GM01

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I've got an 89 with quad sealed beams. If I get the LMC ones suggested earlier in the thread, will I have to splice wires and buy separate bulbs, or are they plug and play? Am looking to upgrade my low beams first and highs later on if the difference is that significant with the lows. Also, unrelated, but does anyone know of any parking light housings that would match better with the headlights? 2 separate bezels per side, for instance?

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mars2878

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I've got an 89 with quad sealed beams. If I get the LMC ones suggested earlier in the thread, will I have to splice wires and buy separate bulbs, or are they plug and play? Am looking to upgrade my low beams first and highs later on if the difference is that significant with the lows. Also, unrelated, but does anyone know of any parking light housings that would match better with the headlights? 2 separate bezels per side, for instance?




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(Pic taken halfway through buffing)


Your mini-quads use a different pigtail than the ones required for the lmc units. Just get the pigtails from a truck w/ composite headlights. Composite headlight trucks use the 9006/9005 bulbs, which is what is used in the lmc units.
 

GM01

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They show in stock right now....
LMC seems to be having some issues with that. It says in stock on the website, but contacting customer support, they seem to think it isn't in stock.

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Anyone have any other ideas since LMC can't seem to get it together?
 

Knuckle Dragger

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LMC seems to be having some issues with that. It says in stock on the website, but contacting customer support, they seem to think it isn't in stock.

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Anyone have any other ideas since LMC can't seem to get it together?
They're always a PITA to deal with
 

mars2878

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LMC seems to be having some issues with that. It says in stock on the website, but contacting customer support, they seem to think it isn't in stock.

You must be registered for see images attach
You must be registered for see images attach



Anyone have any other ideas since LMC can't seem to get it together?


Hit up your local salvage yards, never know what you'll find.

I found 2 sets of 4 in the past 6 months @ my local yard. The funny thing is that both sets were on a Vandura.
 

GM01

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Hit up your local salvage yards, never know what you'll find.

I found 2 sets of 4 in the past 6 months @ my local yard. The funny thing is that both sets were on a Vandura.
Our pick n pull has been picked clean it seems, all headlights gone or gutted from every GMT they had, except a few composite headlight sets. Am trying to keep the 4 lights, just want to upgrade the weak low beams right now
 

mars2878

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Our pick n pull has been picked clean it seems, all headlights gone or gutted from every GMT they had, except a few composite headlight sets. Am trying to keep the 4 lights, just want to upgrade the weak low beams right now


Gotta get in there sooner, lol


Set up yourself an email/text alert @ row52.com

You'll get an alert when fresh meat is put out in the yard. This may give you a better chance @ needed parts.

Not every self-serve yard uses this, but alot do.

Just don't do Suburban vs Tahoe & what not. Pick-ups get confusing on that system, so do some sun's.

Just do 88-00 chevy, 88-00 gmc, 99-00 Cadillac.
Granted You'll get more models messaged to you, but sometimes that is good. That's how I found out that the vans had the lmc lights.
 

firestoness

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I found this thread about 6 months ago. I've been hell bent on finding these Bosch inserts ever since. So I bought 4 Hi beam lights from Ebay for $50 each and continued to look for the low beams. After much research I've found that the Left hand rule of the road low beam lights are gone. I finally installed the High beam capsules when I took my plow off. The first obstacle I ran into was that the High beam capsule is not made to fit into the low beam bucket. I had to use a flap wheel to grind off the tab on the glass so that the capsule would fit into the bucket. I then wired in two relays to send battery power into the bulbs when triggered by the stock wirings high and low beam wires. I did this due to the stock wiring harness' thin wires. I had decided to remove the assemblies to do the upgrade and found that my passenger side plastic housing was broken and the buckets were fairly corroded. I had several other assemblies I had scavenged over the years and disassembled all of them, using the best 4 buckets I had. There are 4 different buckets one each for the left and right low and high beams. I cleaned and painted the best 4 of the buckets and used a different plastic housing on the passenger side. I took some time to lubricate and free up all 4 of the adjusters while the housings were on the bench, all 8 adjusters freed up nicely. I wired just the low beam filament to the low beam relay on the outer bulbs, and wired the high beam relay to the high beam filament on all 4 bulbs and removed my 4hi relay that I had previously installed to the OEM single filament 4701/4703 sealed beams. I had to lower the adjusters on the outer bulbs slightly and was extremely impressed with the results of the low and high beam brightness. However I still wanted to try to find the right hand rule of the road low beam capsules, so I continued to search for them. While searching for those lights I found a supplier that was advertising 88-89 headlamp assemblies. But when I looked at the pictures I realized that these assemblies had the Bosch inserts installed. New housings, buckets and Bosch inserts. Alas, the low beam inserts were for the the left hand rule of the road. But I bought them anyways. I installed them when they came in and you can't even tell that they are for the wrong side of the road for America. So bought the rest of his inventory. I was going to list them on Ebay for $400 each, but then I felt that I should offer them here first, since the people who really want and need them could get first crack at these impossible to find parts. If you want to retrofit you composite headlamps to the quad headlamp set up, you will have to find used quad headlamp assemblies, that are not damaged, and have salvageable adjusters and then buy Bosch inserts. That will easily set you back $400 for the combined costs. If you are interested in these let me know. I can always part these out to use the inserts in my other vehicle that uses the 4701/4703 bulbs, but wanted to see if anybody out there is as hell bent on buying this set up as I was first. It's an old thread but I found it this year maybe someone else did too. Message me on the GMT400 site. I don't come on every day, but I'll eventually see the message.
 
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