Ford Bronco Dome Light Bulb Size

Ford Bronco dome light bulbs utilize 579 and 578 sizes for interior illumination. The replacement chart covers 1995 to 1996 production specifications.

The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.

Bulb Size by Year Range

Years	Bulb Size
1996	579 (From /1996/)
1996	578 (To 1996)
1995	578 (From 1995)
1995	579 (To 1995)

Bulb Specifications

Description	Bulb Size
ANSI standard (US & Canada). Festoon bulb, 44mm length, end-cap contacts. 12V, 12W.	579
ANSI standard (US & Canada). Festoon bulb, 41mm length, end-cap contacts. 12V, 12W.	578

Other Locations

Additional Notes

The Ford Bronco uses two festoon bulb types for the dome light across its 1995-1996 model years: the 579 and the 578.
Both the 579 and 578 are ANSI-standard bulbs recognized in the US and Canada, operating at 12 volts and 12 watts.
Festoon bulbs are cylindrical lamps that make electrical contact through metal caps at each end rather than through a base socket, which is characteristic of both types listed here.
The 579 measures 44mm in length, while the 578 measures 41mm. Despite sharing identical voltage and wattage ratings, the 3mm difference in length means the two types are not interchangeable.
Within the 1996 Ford Bronco, the 579 applies to units built from a certain point in the model year, while the 578 applies to units built up to 1996, indicating a mid-year fitment variation.
The same split fitment pattern exists in the 1995 model year, where the 578 covers vehicles built from 1995 onward and the 579 covers those built up to that point in the year.
Because both years carry dual fitment designations based on production date, the correct bulb size for a specific vehicle depends on its build date rather than the model year alone.