Ford Bronco Headlight Bulb Size

Additional Notes

• The Ford Bronco headlight specifications span the 1966-1996 model years, covering three distinct bulb technologies: sealed beam units (H6024 and H6054), and dual-filament halogen bulbs (9004 and 9007).
• The H6024 is a 7-inch round sealed beam unit operating at 12V. It is an ANSI-standard sealed beam, meaning the lens, reflector, and filament are fused into a single glass unit that is replaced as a whole rather than by swapping an internal bulb.
• The H6054 is a 5x7-inch rectangular sealed beam unit, also operating at 12V under the same ANSI standard. Like the H6024, the entire unit is replaced when the light fails, as no separate internal bulb exists.
• The 9004 is a dual-filament halogen bulb with a P29t base, rated at 12V with 65W on high beam and 45W on low beam. Both beams are served by a single replaceable bulb, which is a key distinction from sealed beam designs.
• The 9007 is a dual-filament halogen bulb with a PX29t base, rated at 12V with 65W on high beam and 55W on low beam. The PX29t base differs physically from the P29t base of the 9004, making the two types non-interchangeable despite their similar appearance.
• For the Ford Bronco, the 1978 model year is the only year in the specifications where two different bulb sizes are listed for the same function. Vehicles equipped with 2 round headlamps use the H6024, while those equipped with 2 rectangular headlamps use the H6054, reflecting a mid-generation headlamp housing change.
• The high beam and low beam specifications are identical across all listed years, which reflects the use of dual-filament or dual-function sealed beam units that handle both lighting modes within a single housing.
• The 9004 and 9007 bulbs share a similar dual-filament halogen design but are not interchangeable due to differences in their base configurations. Installing the wrong type risks improper seating and incorrect beam alignment.