89-91 LMC headlight upgrade

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gmbellew

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I finally got around to upgrading the headlights on the 1990 suburban. I had previously added relays when I was using sealed beams, and that definitely made an improvement in down range light.

LMC finally had their upgrade lights in stock that take 9006xs (low beam) and 9005xs (high beam) bulbs. They definitely threw more light than the sealer beams, but I was still not entirely impressed. especially with the low beams.

so I did some research on here and found that others had used 9012 bulbs (same 55w, but 87% more lumens) in place of the 9006xs bulb. I had to trim the headlight bucket at the bottom to make room for the bulb socket because it is a 90deg base vs the straight base of the 9006xs bulb. I used a dremel to cut vertical cuts and then just bent the tab back and forth until it broke off to clear the bulb base.

I will say that the 9012 bulbs REALLY woke up the headlights. I am finally happy with the downrange light. there is a good cutoff and plenty of light. I run some wide angle LED fog lights that are pretty bright. The fogs dont overpower the 9012 bulbs and it is pretty impressive.

Anybody looking to make the upgrade won't be dissapointed for a total investment of about $250.

I did try to smash a 9005 bulb in to the high beam, but just trimming the bucket wasn't enough. I was going to have to also cut into the core support and didn't feel like doing that as the 9005xs bulbs are plenty adequate.

just thought I would throw this info out there for others looking for more light.
 

SirRobyn0

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I finally got around to upgrading the headlights on the 1990 suburban. I had previously added relays when I was using sealed beams, and that definitely made an improvement in down range light.

LMC finally had their upgrade lights in stock that take 9006xs (low beam) and 9005xs (high beam) bulbs. They definitely threw more light than the sealer beams, but I was still not entirely impressed. especially with the low beams.

so I did some research on here and found that others had used 9012 bulbs (same 55w, but 87% more lumens) in place of the 9006xs bulb. I had to trim the headlight bucket at the bottom to make room for the bulb socket because it is a 90deg base vs the straight base of the 9006xs bulb. I used a dremel to cut vertical cuts and then just bent the tab back and forth until it broke off to clear the bulb base.

I will say that the 9012 bulbs REALLY woke up the headlights. I am finally happy with the downrange light. there is a good cutoff and plenty of light. I run some wide angle LED fog lights that are pretty bright. The fogs dont overpower the 9012 bulbs and it is pretty impressive.

Anybody looking to make the upgrade won't be dissapointed for a total investment of about $250.

I did try to smash a 9005 bulb in to the high beam, but just trimming the bucket wasn't enough. I was going to have to also cut into the core support and didn't feel like doing that as the 9005xs bulbs are plenty adequate.

just thought I would throw this info out there for others looking for more light.
I'm running the Hella Buckets with the H4 bulb, and also Hella 550 fogs. If your interested in what I did it's in this thread. https://www.gmsquarebody.com/threads/headlight-driving-lights.34990/ And like you found with what you did it was a night and day difference. My truck is also a 2 light system and it sounds like yours is a 4. I have the LMC relay kit, but have not installed it simply because I'm no longer having issues with enough light, but still want to cause of course it's easier on the switches and wiring.

The only reason i went with Hella over LMC was because Hella had the stuff I needed in stock. LMC didn't, I'm guessing they are pretty similar.
 

Big Chip

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I'm running the Hella Buckets with the H4 bulb, and also Hella 550 fogs. If your interested in what I did it's in this thread. https://www.gmsquarebody.com/threads/headlight-driving-lights.34990/ And like you found with what you did it was a night and day difference. My truck is also a 2 light system and it sounds like yours is a 4. I have the LMC relay kit, but have not installed it simply because I'm no longer having issues with enough light, but still want to cause of course it's easier on the switches and wiring.

The only reason i went with Hella over LMC was because Hella had the stuff I needed in stock. LMC didn't, I'm guessing they are pretty similar.
I upgraded to the Hellas and relays a few years ago and can confirm it's the way to go!
 

timbritton

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I put in relays one for each bulb with new 14 ga wire supplied from the battery of course fused so Full voltage is supplied. What a difference lights are bright no more flashlight going down the road.
 

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Is anyone able to tell me what type of replaceable bulb the headlights from LMC truck use?
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SirRobyn0

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Is anyone able to tell me what type of replaceable bulb the headlights from LMC truck use?
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I think, like the Hella's I've got, that they run the H4 bulbs. I'm pretty sure either @Ellie Niner or @77 K20 is running the LMC units, though it's been since last winter that we talked lighting so I might be wrong.
 

shanegtr

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I think, like the Hella's I've got, that they run the H4 bulbs. I'm pretty sure either @Ellie Niner or @77 K20 is running the LMC units, though it's been since last winter that we talked lighting so I might be wrong.
That would cool if they just have the H4s. I'll wait to see what Ellie Niner or 77 K20 say.
My lenses are getting a little past their use by and I've been tossing up weather to do some extra work and replace the 92x150mm lenses with the more common 4x6" lenses - but obviously to do that will require new headlight buckets and some trimming of the headlight surround trim. I'd rather a direct replacement for ease.
 

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9006xs (low beam) and 9005xs (high beam)
 

shanegtr

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9006xs (low beam) and 9005xs (high beam)
Ah bugger, was hoping they where going to be H4. That would have made it too easy for my as my outers are H4 already. Inners I can deal with what ever bulb is there but it would have been nice for a twin filament bulb for the outer lights
 

Ellie Niner

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@SirRobyn0 -- I've got the stacked square 6 1/2 x 4" headlights, and am currently running stock 4652 and 4651 non-halogen sealed beams (WTF is wrong with me, eh?). I did have Cibié lamps that used an H4 in the low beam and an H1 high some time ago, but some ****** stole them... not sh¡tting! Does 77 K20 have another truck besides his 1977? I thought he was running some flavor of 7" round Hellas?

@shanegtr -- I was thinking about the work the OP had to do to get the HIR2 (9012) bulbs in the LMC low beams, and I definitely would go to the bother of fitting HIR1 (9011) bulbs in the highs... and then it dawned on me that you're going to need headlamps for left hand traffic (oncoming vehicles pass by you on the right), so these LMC units won't work in your application... especially the low beams. I think GM used headlamps made by Bosch on export vehicles, and the bad news is that they've been discontinued for many years, and are pretty much unobtanium now. I know this is on another forum, but here's a link to a relevant thread on these headlamps: E-Code 92 x 150 headlamps. There's still a ton of options out there for 6 1/2 x 4 headlamps, but I'm pretty sure you'd have replace the header panel/radiator support too.
 

shanegtr

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@SirRobyn0 -- I've got the stacked square 6 1/2 x 4" headlights, and am currently running stock 4652 and 4651 non-halogen sealed beams (WTF is wrong with me, eh?). I did have Cibié lamps that used an H4 in the low beam and an H1 high some time ago, but some ****** stole them... not sh¡tting! Does 77 K20 have another truck besides his 1977? I thought he was running some flavor of 7" round Hellas?

@shanegtr -- I was thinking about the work the OP had to do to get the HIR2 (9012) bulbs in the LMC low beams, and I definitely would go to the bother of fitting HIR1 (9011) bulbs in the highs... and then it dawned on me that you're going to need headlamps for left hand traffic (oncoming vehicles pass by you on the right), so these LMC units won't work in your application... especially the low beams. I think GM used headlamps made by Bosch on export vehicles, and the bad news is that they've been discontinued for many years, and are pretty much unobtanium now. I know this is on another forum, but here's a link to a relevant thread on these headlamps: E-Code 92 x 150 headlamps. There's still a ton of options out there for 6 1/2 x 4 headlamps, but I'm pretty sure you'd have replace the header panel/radiator support too.
You are right, ideally the headlights will need to be for a RHD, which does complicate things somewhat. I did read on one of our local Facebook pages that someone had used 80 series landcruiser headlight buckets (the quad headlight not the single lx450/sahara one piece unit).I'll probably look at going this way - will require some trimming but will be doable
 

SirRobyn0

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@SirRobyn0 -- I've got the stacked square 6 1/2 x 4" headlights, and am currently running stock 4652 and 4651 non-halogen sealed beams (WTF is wrong with me, eh?). I did have Cibié lamps that used an H4 in the low beam and an H1 high some time ago, but some ****** stole them... not sh¡tting! Does 77 K20 have another truck besides his 1977? I thought he was running some flavor of 7" round Hellas?
Well doesn't that just show you how good my memory is. As far as I know 77 K20 has his square and a could modern VW's, but I could be wrong. Your right he has the round eye and euro Hella's BC He wanted the wider high low spread for off road I believe.
 

77 K20

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Well doesn't that just show you how good my memory is. As far as I know 77 K20 has his square and a could modern VW's, but I could be wrong. Your right he has the round eye and euro Hella's BC He wanted the wider high low spread for off road I believe.

I have the glass Hella 7" round headlight housings. They take the H4 bulb... But you were almost right with the LMC idea- I did buy the LMC headlight relay wiring kit.


full
 

SirRobyn0

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I have the glass Hella 7" round headlight housings. They take the H4 bulb... But you were almost right with the LMC idea- I did buy the LMC headlight relay wiring kit.


full
Oh yeah I've got one of those LMC headlight wiring relay kits too but I've never put it in probably should do that before winter huh?
 

77 K20

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Oh yeah I've got one of those LMC headlight wiring relay kits too but I've never put it in probably should do that before winter huh?

My fingers work better when they aren't cold- but you do have a bit warmer temps over there. It would be ideal to pick a nice 65-70 degree day...
 

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