Third brake light leds?

[chevyrider838]

Has anyone experienced any issues switching your bulbs to leds in your factory third brake light assembly? Thx!

 

[df2x4]

Yes. Be really careful with LEDs in those sockets. The way they're designed, the base of many LEDs will create a short when you press the brake and blow 20A fuses/make things smoke. I wouldn't recommend it personally after experiencing that on my red truck. I avoided letting the smoke out but it blew the CTSY fuse every time I hit the brakes or turned the cargo lights on.

If you insist on trying it, compare the base of your LEDs to the standard bulb bases first. If the LED bases are any larger than the standard bulbs in any dimension, it's not going to work properly.

 

[Knuckle Dragger]

This is what I ran into https://www.gmt400.com/threads/switching-to-led-external-lights-and-ran-into-this.44311/

 

[chevyrider838]

Yes. Be really careful with LEDs in those sockets. The way they're designed, the base of many LEDs will create a short when you press the brake and blow 20A fuses/make things smoke. I wouldn't recommend it personally after experiencing that on my red truck. I avoided letting the smoke out but it blew the CTSY fuse every time I hit the brakes or turned the cargo lights on.

If you insist on trying it, compare the base of your LEDs to the standard bulb bases first. If the LED bases are any larger than the standard bulbs in any dimension, it's not going to work properly.

Ok thanks!

 

[618 Syndicate]

Better off buying a led light, can often find them cheaper than replacement bulbs too.

 

[Nad_Yvalhosert]

Yup, found out by accident that LED's listed as CK3157 are the correct application. CK as in GM truck C and K trucks...
Also, I found that the white LEDs show up pink in the tail lights. Buy the red ones and test for polarity in the socket and "bulb" before installing. The LEDs are polarity sensitive.

 

[df2x4]

Yup, found out by accident that LED's listed as CK3157 are the correct application. CK as in GM truck C and K trucks..

The CK LEDs are only necessary in the middle socket of the tail lights. The OP was asking about the third brake light on the back of the cab. It takes 921 bulbs.

 

[Nad_Yvalhosert]

The CK LEDs are only necessary in the middle socket of the tail lights. The OP was asking about the third brake light on the back of the cab. It takes 921 bulbs.

Apologies, I missed that part. Seeing as my Yukon and Suburban are OE LEDs, I only thought of the left and right brake lights.
And seeing as OP didnt specify that he has a pickup...

 

[chevyrider838]

Apologies, I missed that part. Seeing as my Yukon and Suburban are OE LEDs, I only thought of the left and right brake lights.
And seeing as OP didnt specify that he has a pickup.

‍Makes no difference whether pickup was mentioned…”third brake light”, however, was mentioned.

 

[Nad_Yvalhosert]

‍Makes no difference whether pickup was mentioned…”third brake light”, however, was mentioned.

Right. And the SUV's were LED from the factory. Hence my mea culpa.

And thank you for resurrecting a 15 month old thread.