I misunderstood the intent.
1156 bulbs are the most common bulb which uses the Ba 15s base and will yield the most hits on Amazon.
As somebody who has ordered dozens of LED bulbs on Amazon, it really is a crapshoot whether the light output and color will be acceptable, The amp draw will certainly be much less, but many bulbs are very bluish, and I personally Despise blue in my white, and do not get me started on those who install blue HID kits into their halogen light housings for vehicular headlamps.
Generally, LED bulbs in incandescent fixtures do not make good use of the reflector. Many times the only effective light will come from the individual LEDS pointed downward, on a ceiling mounted reflector.
There are some LEDS designed to fire all their light in only one direction and not even bother trying to make use of the reflector. Reflectors are designed around a very bright precisely positioned filament and radially firing LEDs attempts to mimic this fail and often fail miserably.
http://www.amazon.com/Gold-Stars-11...UTF8&qid=1425952986&sr=8-10&keywords=1156+LED
The LED bulbs suitability in your lighting fixture will vary widely depending on bulb and fixture and reflector and lens design.
There are also warm white LED bulbs that are a color closer to incandescent, but in general these are a smidge dimmer.
I recommend getting extremely bright 5050 SMD LEDs, and then taming them with a pwm dimmer if needed, but there are some bulbs which will not respond to a pwm dimmer. Usually these will say 10 to 30V DC input voltage.
http://www.amazon.com/Triangle-Bulb...qid=1425953614&sr=8-1&keywords=pwm+led+dimmer
Please do not try and use retrofit LED bulbs in Signal markers on the vehicles safety lighting. Especially dual filament bulbs, as there is not enough brightness difference between running and signal light, and often they are nearly invisible at off angles.
Phillips is making some LED retrofit lights that are DOT compliant, but only in some vehicle's reflectors. Using LED bulbs in housings designed for incandescent bulbs on exterior vehicular lighting is illegal and can be dangerous.
Just because there are millions of ricers doing it does not make it acceptable, nor an improvement, only different.