1969 GMC headlight conversion and wiring questions. - The 1947 - Present Chevrolet & GMC Truck Message Board Network

**desert-rat** · 12-09-2013, 07:08 PM

Are the headlights 5 3/4" or 7"??
I don't have the truck with me right now, but I'm looking to buy a pair of low beams conversion where all I have to replace is just the bulb and not the whole unit.
Also, can I use the stock wiring or will I need to buy an adapter to work with the new headlights??
I made calls to after market places, but can't get a straight answer.
Thanks.

463 · 12-09-2013, 08:04 PM

Cibie H4 & H1 headlamps • 5.75” round for the low and hi. These have a H4 for the low and H1 for the hi beam. Note with this light upgrade I recommend the head lamp relay wire upgrade is installed in the truck. link http://www.madelectrical.com/catalog/rly-1.shtml
here is a link http://www.danielsternlighting.com/p.../products.html
Or the seal beams from http://www.sylvania.com/en-us/applic...n.aspx#fldYear

Ole Greenie · 12-09-2013, 08:19 PM

Quote:

Originally Posted by desert-rat

Are the headlights 5 3/4" or 7"??
I don't have the truck with me right now, but I'm looking to buy a pair of low beams conversion where all I have to replace is just the bulb and not the whole unit.
Also, can I use the stock wiring or will I need to buy an adapter to work with the new headlights??
I made calls to after market places, but can't get a straight answer.
Thanks.

We have 7" headlights. IMO, this is a real easy upgrade. Go down to the local pick-a-part and pull off 2 5-prong square relays. Do a search for the upgrade wire diagrams and install it all your self with good 14/16 gage wire from Autozone... You will save a ton. The headlights can be had on Ebay for less than $45. Total in mine was $60, and bright as heck!

Critter · 12-09-2013, 08:26 PM

"We" as in chevy owners have 7" lights but desert-rat has a GMC emblem under his name with tells me he has 4 head lights. They are not 7", they are smaller. I don't know the exact dimension but 5.75" sounds about right. I'm sure a GMC guy will chime in here in a second.

463 · 12-09-2013, 09:11 PM

Chev is 7" lights (2 headlamps) GMC is a 5.75” light (4 headlamps) setup.

**desert-rat** · 12-09-2013, 09:23 PM

So buying the head lamp relay wire upgrade will come with everything that I need to get the headlight conversion to work??

463 · 12-09-2013, 09:47 PM

Quote:

Originally Posted by desert-rat

So buying the head lamp relay wire upgrade will come with everything that I need to get the headlight conversion to work??

In most cases the kit is complete , you may want to move or relocate to you liking and that may require more wire. you need 2kits hi and low.

**desert-rat** · 12-09-2013, 10:54 PM

So all and all, this is a pretty straight forward install??

463 · 12-10-2013, 10:36 AM

Yes! It's one of the top five upgrades for my money.

Warrens69GMC · 12-10-2013, 11:58 AM

LMC Truck has your harness already made with both high and low beam relays $29.99+ shipping.
part -36-3581

http://www.lmctruck.com/icatalog/cb/full.aspx?Page=76

**desert-rat** · 12-10-2013, 01:32 PM

Quote:

Originally Posted by Warrens69GMC

LMC Truck has your harness already made with both high and low beam relays $29.99+ shipping.
part -36-3581

http://www.lmctruck.com/icatalog/cb/full.aspx?Page=76

Will this wire complete the installation or do I need to get the headlight bulb adapter to work with the conversion bulb??

12-09-2013, 07:08 PM	#1
desert-rat Senior Member Join Date: Jan 2013 Location: 3,018 feet above the SoCal/Mojave Desert region. Posts: 357	1969 GMC headlight conversion and wiring questions. Are the headlights 5 3/4" or 7"?? I don't have the truck with me right now, but I'm looking to buy a pair of low beams conversion where all I have to replace is just the bulb and not the whole unit. Also, can I use the stock wiring or will I need to buy an adapter to work with the new headlights?? I made calls to after market places, but can't get a straight answer. Thanks.

12-09-2013, 08:04 PM	#2
463 Registered User Join Date: Nov 2007 Location: Sask Canada Posts: 1,666	Re: 1969 GMC headlight conversion and wiring questions. Cibie H4 & H1 headlamps • 5.75” round for the low and hi. These have a H4 for the low and H1 for the hi beam. Note with this light upgrade I recommend the head lamp relay wire upgrade is installed in the truck. link http://www.madelectrical.com/catalog/rly-1.shtml here is a link http://www.danielsternlighting.com/p.../products.html Or the seal beams from http://www.sylvania.com/en-us/applic...n.aspx#fldYear __________________ Trueman

12-09-2013, 08:26 PM	#4
Critter Future TOTM Winner Join Date: Aug 2006 Location: Bulverde, TX Posts: 2,692	Re: 1969 GMC headlight conversion and wiring questions. "We" as in chevy owners have 7" lights but desert-rat has a GMC emblem under his name with tells me he has 4 head lights. They are not 7", they are smaller. I don't know the exact dimension but 5.75" sounds about right. I'm sure a GMC guy will chime in here in a second. __________________ 72 Chevy CST K5 HIGHLANDER BLAZER Getting a 6.0,NV4500,NP205,14BFF (Currently laying all over the place in little pieces) 72 Chevy swb step-side "LS" 6.0 Here's a build thread of sorts 2002 HD2500 Crew Cab, 8.1L Allison 4x4 Daily Driver Check it out www.lsdyno.com

12-09-2013, 09:11 PM	#5
463 Registered User Join Date: Nov 2007 Location: Sask Canada Posts: 1,666	Re: 1969 GMC headlight conversion and wiring questions. Chev is 7" lights (2 headlamps) GMC is a 5.75” light (4 headlamps) setup. __________________ Trueman

12-09-2013, 09:23 PM	#6
desert-rat Senior Member Join Date: Jan 2013 Location: 3,018 feet above the SoCal/Mojave Desert region. Posts: 357	Re: 1969 GMC headlight conversion and wiring questions. So buying the head lamp relay wire upgrade will come with everything that I need to get the headlight conversion to work??

12-09-2013, 10:54 PM	#8
desert-rat Senior Member Join Date: Jan 2013 Location: 3,018 feet above the SoCal/Mojave Desert region. Posts: 357	Re: 1969 GMC headlight conversion and wiring questions. So all and all, this is a pretty straight forward install??

12-10-2013, 10:36 AM	#9
463 Registered User Join Date: Nov 2007 Location: Sask Canada Posts: 1,666	Re: 1969 GMC headlight conversion and wiring questions. Yes! It's one of the top five upgrades for my money. __________________ Trueman

12-10-2013, 11:58 AM	#10
Warrens69GMC Registered User Join Date: Jan 2003 Location: Safford,AZ Posts: 3,613	Re: 1969 GMC headlight conversion and wiring questions. LMC Truck has your harness already made with both high and low beam relays $29.99+ shipping. part -36-3581 http://www.lmctruck.com/icatalog/cb/full.aspx?Page=76



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