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Cab Marker Lights

cbgrant74
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cbgrant74 Enthusiast

cbgrant74

Posted
Posted

I am planning to install cab marker lights on my 2015 Silverado 1500. (Why? Because I think it looks cool.) I have the GM lights and wiring harness, I know how to locate the lights in the right position on the roof, and I know how I’m going to make the required square holes.

 

What I need is a little bit of information about how the clips on the bottom of the lights engage the underside of the roof. Below are a couple of photos of a mockup I made, showing the bottom of a light installed through a square hole in a piece of sheet metal. As you can see, there is a steel clip with four legs, one at each corner of the hole. Tightening the bolt in the center of the clip pulls it towards the body of the light, pressing the legs against the underside of the roof.

 

Light%201_zps2zepmk2p.jpg

 

Light%202_zpsiniflass.jpg

 

Are the clips tightened until the legs are “just snug” against the bottom of the roof, as in the photos? Or, are they tightened all the way down, splaying the legs out away from the hole? Neither of these seem very secure. Alternatively, is there some sort of retainer that I don’t have that keeps the legs from splaying out as the clip is tightened?

 

What would be most helpful is a photo of the bottom of a factory-installed light (why I’m posting this in the 2500/3500 forum).

 

Thanks in advance.

  • 1 year later...
STKR Enthusiast

STKR

Posted
Posted

A little late, but I just read in another thread that you tighten them until the roof light housing is snug against the exterior roof.  It would also help to add a little silicone as a backup to the foam gasket.  I will be adding some blue Loctite to the clamp bolts as well.

 

Question:  You said you know how to locate the holes.  Can you share the information you have?

 

Thanks,

Jim

CuzznVinny Enthusiast

CuzznVinny

Posted
Posted

mine came with loctite already on the bolt. The square hole needs to be a perfect 3/4" square. push it thru and the black plastic has tabs that will catch and semi hold it down. Tighten the bolt all the way down and the metal clip will spread and pull it tight. the lights have a double gasket and should not leak, I added 100% silicone around the perimeter of the hole just to be safe.

Catman HD Enthusiast

Catman HD

Posted
Posted

I seen somewhere on this forum that a guy had a die that cut perfect holes. He was selling for like 80.00 says he bought cut his holes and no longer needed. Dye looked like you center drill hole then dye tightens and makes 3/4" square hole. He says he paid 120.00 I think... Just an fyi for help.

2014sierra-rich Enthusiast

2014sierra-rich

Posted
Posted

Anyone have pictures of the job done? Were you going with the yellow marker lights or I have seen white led cab lights? Thanks


Sent from my iPhone using Tapatalk

  • 1 year later...
Linecapt Enthusiast

Linecapt

Posted
Posted

Finally got it done, courtesy of Truck Toyz Unlimited in Rocky Hill, CT.

 

c48f45dc-d87e-4f66-a494-38410534c7e0.PNG

  • 1 year later...
Chebu70 New Member

Chebu70

Posted
Posted

Hey folks, thanks for the write-up!  I have found myself in the same situation with a 2020 HD that I didn’t realize could possibly come without the roof market lights.  Side note, I had a 2000 for 19 years that had a rusted shift linkage clip and when I thought it was in park, it was actually in reverse, and rolled into the neighbors house...  never thought I would buy a new truck.  But here we are.  
 

Fortunately, it appears that the 2020 comes with the main harness already installed and I just need to run the roof harness and cut the holes in the roof... “just” cutting holes in a brand new truck. 
 

Is the 3/4” square punch still floating around?  

  • 3 weeks later...
94yj Enthusiast

94yj

Posted
Posted
On 8/7/2020 at 6:28 AM, Chebu70 said:

Hey folks, thanks for the write-up!  I have found myself in the same situation with a 2020 HD that I didn’t realize could possibly come without the roof market lights.  Side note, I had a 2000 for 19 years that had a rusted shift linkage clip and when I thought it was in park, it was actually in reverse, and rolled into the neighbors house...  never thought I would buy a new truck.  But here we are.  
 

Fortunately, it appears that the 2020 comes with the main harness already installed and I just need to run the roof harness and cut the holes in the roof... “just” cutting holes in a brand new truck. 
 

Is the 3/4” square punch still floating around?  

i just had a shop do mine and i have the 3/4 square punch i now do not need if you like message me thanks

Chebu70 New Member

Chebu70

Posted
Posted
18 minutes ago, 94yj said:

i just had a shop do mine and i have the 3/4 square punch i now do not need if you like message me thanks

Thanks Bill!  I'll send you a pm now.  Appreciate it.  What year did you punch out?

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