There is more to wattage when your talking LEDs .
What's the optics, spot or flood?
Are they using a current driver to power the LEDs?
What type of LEDs? SMT, superflux, star etc
What brand, or who made the LEDs?
What color or CCT are the LEDs?
Do you have a link to the product?
As for heat, high powered LEDs will create quite a bit of heat.
Heat is actually something that has to be thought through and a plan made. DIY / custom high powered LEDs require heat sinking and possibly fan cooling as well.
Regular cheap 5mm through hole round LEDs won't create much heat if anything at all but their light output is crap for raps vehicles.
As for the transport truck taillights, there is A LOT of led tail lights on the market. The cheaper they are means they won't last as long, also usually the less output of light you can see, which usually is less heat.
LEDs don't like running outside the comfort zone. (Voltage) the more an led is ran outside its comfort zone the less it's life expectancy is.
Most LEDs run on 2-4VDC of power to Vehicles electrical system is 12. But in real life it is 13.6-15vdc .
When your alternator spikes it's killing the LEDs.
Because of the power spikes a power current driver to regulate and power the LEDs a recommended.
The driver will regulate the voltage, keeping a perfect 12 or 9vdc depending on the array of LEDs and how they are wired. But also will boost the current and force additional power thru the LEDs. By doin so they will get warm, and hot and burn up in a matter of minutes as they will need dissipate the heat.
LEDs are not always brighter then halogens. In fact most halogen put out more light output then a lot of LEDs by themselves.
Also LEDs are very directional. Meaning they need a reflector and a lot more leds to compensate.
Because LEDs are very directional, slapping them into Halogen reflector that is based on 360degrees of light to reflect it in a certain direction doesn't work out well. Because LEDs shoot out forward often 70-110 degree a lot of light doesn't hit the reflector. They have started out with these 360degree led bulbs but that still are.
And so on. Lol.
I got more but I'm on my phone. And kids need my attention. Lol
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