LEDs for Special T Auto third brake light

[jangell]

Not sure how many people have Hervey's third brake light (HCSL, CHMSL, whatever you want to call it), but I recently switched out my tail light bulbs with LEDs, and decided to do the ones in that as well. My understanding is that this unit is from a Corvette C4, specifically the ZR1 (https://www.google.com/search?q=corvette+c4+zr-1+CHMSL&client=safari&rls=en&tbm=isch&source=lnms&sa=X&ved=0ahUKEwjrtaDGg__mAhU9UBUIHS_KAooQ_AUImQEoAQ&biw=1532&bih=1590) from the look of the pictures in a Google search.

The standard halogen bulbs have G4-style bases, and they're pretty small. The best match I found was on SuperBrightLEDs.com, the G4-WW2-COBW (https://www.superbrightleds.com/moreinfo/miniature-and-subminiature-bulbs/g4-bi-pin-led-light-bulb-20w-equivalent-180-lumens-12v-dimmable/5685/13031/). They just fit in the housing, although you might have to bend the pins out a little bit to get them installed. The warm white ones look properly red through the red lens, not pink like cooler lights might look.

The first two pictures have one LED installed, and the rest are the original halogens. The last photo is the final install with all LEDs.

62314 62313 62315

-- Joe

[Bitsyncmaster]

Didn't they have those LEDs in red? It's always better to match the LED color with the color of the lens.

[jangell]

Ah, I should have mentioned that -- these bulbs seems be more commonly used in reading lamps, so they only had them in cool and warm white. They had no colored versions at all. I used matching colors for my tail lights, but I was stuck with warm white on these bulbs.

-- Joe

[Farrar]

Thanks for this info! I plan to use the C4 third brake light and you just saved me the trouble of shopping around for LEDs. :thumbup2:

[DMCVegas]

My understanding is that this unit is from a Corvette C4, specifically the ZR1 (https://www.google.com/search?q=corvette+c4+zr-1+CHMSL&client=safari&rls=en&tbm=isch&source=lnms&sa=X&ved=0ahUKEwjrtaDGg__mAhU9UBUIHS_KAooQ_AUImQEoAQ&biw=1532&bih=1590) from the look of the pictures in a Google search.

Negative. It is indeed a C4 only part (NOT the same as the F-Body), but it isn't limited to the ZR-1. GM *did* apparently have a production change at one point that limited it's use. The C4 convertible version had the CHMSL mounted in the rear fascia, and apparently at some later cars with hard tops have that fascia instead. So for anyone who goes searching junkyards for these parts, make sure you verify which CHMSL you're getting.