For the 2012 Ford F-250, both the low-beam and high-beam headlights use an H13 bulb. The supplied fitment data does not list a separate headlight bulb for different headlight types or configurations, so verify the existing bulb before ordering if your truck has aftermarket or modified housings.
The front fog lights use 9145 LED bulbs. Exterior lighting includes 3157 bulbs for the front turn signals, parking lights, brake lights, tail lights, rear turn signals, and rear side markers. The front side markers use 2825 bulbs. Reverse lights use 921 bulbs, while the license plate and courtesy lights use 194 bulbs.
For interior and service lighting, the dome light uses a 578 bulb, map lights use 906, the glove box uses 161, the trunk light uses 912, and the engine light uses 906. Check the original bulb and socket when replacing any LED-equipped or modified lighting.