Has anyone noticed that their Center High Mount Stop Light (3rd brake light) bulb has burnt out?

JimCost2014 · August 20, 2022

I just noticed the other day that mine was not working. Checked fuse in UH box, was good, so pulled the light housing off to find the bulb burnt out.

It looked like a mini nuclear explosion happened inside of it. There was soot all along the socket and even some inside the housing itself.

Took this as an opportunity to finally change my cargo lamps and the 3rd BL bulb to LEDS, has been working fine since.

But now that this has happened, I have the "Spidey sense" and have been noticing that there are lot of K2's driving around with the 3rd BL bulb not working, both 1500's and HD's.

Just curious how many this has happened to.

Edited August 20, 2022 by JimCost2014

rav3 · August 20, 2022

Nope, hadn't noticed. BUT, I too replaced the cargo lights to LED bulbs

OffTheAir · August 20, 2022

So crazy to see this thread, I literally just changed my oil yesterday and noticed it. When it went out the first time I figured it was because, you know, the housing was leaking and there was literally a pool of water inside of it.

However, now that it has gone out again (I think it's maybe only been a little over a year since changing it?), I'm genuinely really curious about what causes them to fail so prematurely. Cargo lamps work perfectly fine, it's just that pesky third brake light.

I guess it's just shocking to me because I literally can't even remember when I changed the tail lights, meanwhile I feel like I'm always checking on this third brake light, haha

JimCost2014 · August 20, 2022

14 minutes ago, OffTheAir said:

Cargo lamps work perfectly fine, it's just that pesky third brake light.

Well said!

Yotaman · August 23, 2022

Count me in, my cargo is fine but had rarely been used but brake is dead. I just ordered a new gasket and LED's

15 Z71 · August 24, 2022

Mine has been out for a while. I got the bulb at napa was like 3 dollars. I'm to nervous to change it because mine does not leak. Worried if I do change it,it will start leaking.

Edited August 24, 2022 by 15 Z71

midwestdenaliguy · August 24, 2022

My guess is because the mounting screws on the ends of the housing are closer to the cargo lights they keep a tighter seal. While the middle where the brake light is has a weaker seal. Complete guess though. I'd replace your seal to be safe. First thing I did when I bought the truck was replace all the incandescent bulbs with LED bulbs. I've never had any go out prematurely. If you replace them with incandescent bulbs don't touch them with your bare fingers, the oil on them can cause premature failure. I just replaced my cargo/brake light seal since the truck is now 6 years old and I go through a car wash about once a week. Don't want to take any chances with leaks into the cabin. It's cheap insurance.

Edited September 19, 2022 by midwestdenaliguy

JimCost2014 · August 25, 2022

11 hours ago, 15 Z71 said:

Worried if I do change it,it will start leaking.

Same thought process, but I did not want to get pulled over for it not working. Think in Washington state, it is not necessary for it to be working, but don't want to find out either.

I will say the housing was in very good shape, along with the gasket.

JimCost2014 · August 25, 2022

9 hours ago, midwestdenaliguy said:

My guess is because the mounting screws on the end of the housing are closer to the cargo lights they keep a tighter seal and the middle where the brake light is has a weaker seal. Complete guess though. I'd replace your seal to be safe. First thing I did when I bought the truck was replace all the incandescent bulbs with LED bulbs. I've never had any go out prematurely. If you replace them with incandescent bulbs don't touch them with your bare fingers, the oil on them can cause premature failure. I just replaced my cargo/brake light seal since the truck is now 6 years old and I go through a car wash about once a week. Don't want to take any chances with leaks into the cabin. It's cheap insurance.

Part number for the gasket/seal?

Spurshot · August 25, 2022

I have a topper on my truck and really don't see the third brake light or the cargo lights. My SnugTop has LEDs for the brake light. I did change a couple brake light (incandescent) bulbs a couple years ago.

I'm kind of torn on the LED conversion. Don't all of them have resistors to control the flickering? The resistor effectively makes them use current like an incandescent bulb, is my understanding.

steelerdude15 · August 25, 2022

2 hours ago, Spurshot said:

I have a topper on my truck and really don't see the third brake light or the cargo lights. My SnugTop has LEDs for the brake light. I did change a couple brake light (incandescent) bulbs a couple years ago.

I'm kind of torn on the LED conversion. Don't all of them have resistors to control the flickering? The resistor effectively makes them use current like an incandescent bulb, is my understanding.

One of the first things I did to my truck was change the high mounted cargo lamps. I used standard Sylvania LED bulbs. I did not change third brake light bulb. I did that almost three years ago and I haven't had any issues with them at all.

JimCost2014 · August 25, 2022

3 hours ago, Spurshot said:

I have a topper on my truck and really don't see the third brake light or the cargo lights. My SnugTop has LEDs for the brake light. I did change a couple brake light (incandescent) bulbs a couple years ago.

I'm kind of torn on the LED conversion. Don't all of them have resistors to control the flickering? The resistor effectively makes them use current like an incandescent bulb, is my understanding.

Most of the bulbs are polarity specific, if it does not work, rotate it 180 degrees, but no flickering. No issues with my truck.

mikeyk101 · August 25, 2022

14 hours ago, JimCost2014 said:

Part number for the gasket/seal?

Here is a replacement gasket I ordered. I had seen decent online reviews for this and it's supposed to be better than the OEM gasket. However, before it arrived, I ended up with the dreaded third break light leak and ended up bringing it in to the dealer to have them fix the leak under warranty. So the dealer installed a new OEM gasket and I now have this one as a spare in case the leak comes back.

https://www.ebay.com/itm/174035410493?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=nA6hqFjBR_e&sssrc=2349624&ssuid=SX1w3s_iQIW&var=&widget_ver=artemis&media=COPY

I forgot to add, to keep this post on topic, I checked my third brake light last night and mine still works fine. But like @Spurshot mine is hidden behind my Century topper so if it goes out, not a real big deal...

Edited August 25, 2022 by mikeyk101

midwestdenaliguy · August 25, 2022

5 hours ago, Spurshot said:

I have a topper on my truck and really don't see the third brake light or the cargo lights. My SnugTop has LEDs for the brake light. I did change a couple brake light (incandescent) bulbs a couple years ago.

I'm kind of torn on the LED conversion. Don't all of them have resistors to control the flickering? The resistor effectively makes them use current like an incandescent bulb, is my understanding.

Resistors are only needed for blinker bulbs. My truck came with the factory LED head and tail lights so I only needed LED bulbs for the reverse lights in the tails and cargo/third brake lights.

OffTheAir · August 28, 2022

On 8/25/2022 at 1:28 PM, mikeyk101 said:

Here is a replacement gasket I ordered. I had seen decent online reviews for this and it's supposed to be better than the OEM gasket. However, before it arrived, I ended up with the dreaded third break light leak and ended up bringing it in to the dealer to have them fix the leak under warranty. So the dealer installed a new OEM gasket and I now have this one as a spare in case the leak comes back.

https://www.ebay.com/itm/174035410493?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=nA6hqFjBR_e&sssrc=2349624&ssuid=SX1w3s_iQIW&var=&widget_ver=artemis&media=COPY

I forgot to add, to keep this post on topic, I checked my third brake light last night and mine still works fine. But like @Spurshot mine is hidden behind my Century topper so if it goes out, not a real big deal...

So I actually have the Vipmotoz gasket installed in my third brake light from when I first had the leak, and I have to say it has done its job very well! The third brake light has a tiny bit of a larger gap since the gasket is thicker, but this hasn't caused any issues.

The difficult part came when I was changing the brake light the other day, and I had completely forgotten it was in there and that it has double-sided adhesive. Definitely made the light hard to get off, and I was worried because with the amount of force I had to put in, I thought I ripped off the adhesive or at least damaged the gasket in some way.

Unfortunately, I was lazy and thought it looked fine after close inspection. Lo and behold, even after yanking it off there is still no water getting in! Just know that anytime the bulb goes out, it would probably be wise to swap out the gasket. I guess it's not too big of a deal though, since it's literally $10.