xiiiix

my 3rd brake light went out and i'm planning on just getting a LED somewhere online as a replacement. i just wanted to make sure if the bulb size is 921?

alloutt

you can also buy a whole new unit with leds already in it

xiiiix

i've already taken that into consideration but i'm not a really big fan of the look of the led 3rd brake light. i want to keep my stock 3rd brake light unit and simply put an led in it. thanks though!

can anyone verify if the 921-R9 would fit?
http://www.superbrightleds.com/specs/T13_specs.htm

xiiiix

bump. anybody know?

d_ames117

http://www.modifiedlife.com/car-repl...-ford-mustang/

It should fit since it's a 921, but it will draw slightly more current, ~ 30 vs ~20 mA.

xiiiix

would anything bad happen if i put those leds in since they draw more current? sorry if that's a dumb question. i just dont know.

xiiiix

anyone??

foolio2k4

ebay.

157dB

LEDs draw way less current than traditional incandescent filiment bulbs.
They are like 10 times more efficient.

3rd brake light is a 921 as the owners manulal shows.

I think you will find that the bulb is mounted sideways
and the replacement LED you show only puts out light
to the front of it, not the side like a filiment bulb.
I would go for the replacement LED third brake light assembly
and forgo the LED bulb idea.

landon.moss

i have LED bulbs in my 71 and they are a definite improvement over a filament bulb. the 1157s i have do not project light out the sides either, but the taillamps light up and are probably twice as bright as the stock ones, even without the light projecting out - was considering custom housings to relocate the sockets, and i still may eventually, but they work fine now. the only problem some people have on older cars is that running LEDs will not draw enough juice to get the circuit going. i was told i would need to do a lot more work than just replace the bulbs, but i did not. so, imo you should be fine just replacing the bulb - probably a good idea since most mustangs i see have the 3rd brake light out