Ford F-250 Dome Light Bulb Size

The Ford F-250 dome light utilizes bulb sizes 912, 561, 105, 1003, and 81 depending on the specific production period. Available information covers the range of 1953 through 1999.

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
1989-1999	912
1973-1980	561
1969-1972	105
1956-1968	1003
1953-1955	81

Bulb Specifications

Description	Bulb Size
ANSI standard (US & Canada). Wedge bulb (T15). Variant of 921. 12V, 12W.	912
ANSI standard (US & Canada). Festoon bulb, 44mm length, end-cap contacts. 12V, 12W.	561
ANSI standard (US & Canada). Single-filament bulb with BA15s bayonet base. Variant of 1156. 12V, 13W.	105
ANSI standard (US & Canada). Single-filament bulb with BA15s bayonet base. 12V, 21W.	1003
ANSI standard (US & Canada). Single-filament bulb with BA15s bayonet base. 12V, 8W.	81

Other Locations

Additional Notes

The Ford F-250 dome light uses four distinct bulb types across its model history: the 912, 561, 105, 1003, and 81.
The 912 is the most consistently specified bulb in these records, covering the Ford F-250 from 1989-1999. It is a T15 wedge-base bulb rated at 12V and 12W, and it is a variant of the 921.
The 1003 bulb covers the longest single span in the earlier portion of the specifications, appearing in the Ford F-250 from 1956-1968. It uses a BA15s bayonet base and is rated at 12V and 21W, making it the highest-wattage bulb listed across all entries.
The 561 is a festoon-type bulb with a 44mm length and end-cap contacts, rated at 12V and 12W. It is specified for the F-250 from 1973-1980.
The 105 bulb uses a BA15s bayonet base and is rated at 12V and 13W. It is a variant of the 1156 and is specified for the 1969-1972 model years.
The 81 bulb, rated at 12V and 8W, is the lowest-wattage bulb in these specifications and is listed only for the 1953-1955 model years.
The 912 wedge base and the 561 festoon base represent physically incompatible mounting types, meaning they are not interchangeable despite sharing the same 12V and 12W electrical ratings.
The 105 and 1003 both use the BA15s bayonet base, though their wattage ratings differ at 13W and 21W respectively, which affects their suitability as substitutes for one another.
The 81 also uses a BA15s bayonet base, as do the 105 and 1003, though its 8W rating is notably lower than both of the other BA15s-based bulbs in these specifications.
All bulb types listed conform to ANSI standards applicable in the United States and Canada.