I have not tried an LED unit in a car - just in a high intensity lamp. Several companies, including www.LEDtronics.com,
manufacture bayonet base 12V Low current high brightness LEDs that - aside from a narrow beam pattern - should work on a 12 volt auto system if the power is clean enough. (I believe LEDtronics only sells to distributers, but there are a lot of other sites I haven't explored yet from a metacrawler search of 'LED automotive lights'). I know a lot of manufacturers are pushing these for new car tail lights and 3rd brake lights, but I don't know of one made as a specific bulb equiv. replacement. I wonder if the low current draw (1-2 watts) might not appear to be a burned out bulb and mess up the bulb indicator on some cars. That's why I thought about using it with the existing bulb - shouldn't run the current over 35 watts. If I find anything I will post it here.
87 300E 53,000 miles
[This message has been edited by JCE (edited 09-07-1999).]