Subaru DL Dome Light Bulb Size

The Subaru DL dome light utilizes bulb sizes DE3175, 67, 257, and 57 depending on the specific version of the vehicle. Available information covers a span from 1975 through 1989.

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
1985-1989	DE3175
1982-1984	67
1980-1981	257
1975	57

Bulb Specifications

Description	Bulb Size
ANSI standard (US & Canada). Festoon bulb, 31mm length, end-cap contacts. 12V.	DE3175
ANSI standard (US & Canada). Single-filament bulb with BA15s bayonet base. Lower wattage variant of 1156. 12V, 8W.	67
ANSI standard (US & Canada). Festoon or BA9s base instrument bulb. 12V, 2W.	257
ANSI standard (US & Canada). Single-filament bulb with BA9s base. 12V, 1W.	57

Other Locations

Additional Notes

The DE3175 is a festoon-type bulb measuring 31mm in length with end-cap contacts, operating at 12V. It follows the ANSI standard applicable in the US and Canada.
The Subaru DL used the DE3175 as its dome light bulb across the 1985-1989 model years, making it the most consistently specified bulb in these records.
Festoon bulbs make contact at both ends of the bulb body rather than through a base socket, which is a defining characteristic of the DE3175 and a factor relevant to physical fitment.
The bulb 67 is a single-filament type with a BA15s bayonet base, rated at 12V and 8W. It is described as a lower wattage variant of the 1156 bulb, meaning the two share a base type but differ in wattage output.
The Subaru DL used the 67 bulb for the dome light in the 1982-1984 model years. Because the 67 and 1156 share a BA15s base, physical fitment may be possible between them, but the wattage difference makes them non-equivalent replacements.
The 257 is rated at 12V and 2W, and it accommodates either a festoon or a BA9s base configuration. The Subaru DL carried this specification for the 1980-1981 model years.
The BA9s base is a miniature bayonet fitting with a 9mm cap, commonly found in low-wattage instrument and interior lighting applications. Both the 257 and the 57 bulbs use this base type.
The 57 bulb is a single-filament type with a BA9s base, rated at 12V and 1W. It is the lowest wattage bulb in these specifications and was designated for the 1975 Subaru DL dome light.
Three distinct base types appear across these specifications: the end-cap festoon contact of the DE3175, the BA15s bayonet of the 67, and the BA9s bayonet shared by the 257 and 57. These differences mean bulbs from different model years are not physically interchangeable without a socket adapter.
All four bulb types in these specifications conform to ANSI standards for the US and Canadian markets, indicating standardized electrical and physical tolerances within those respective bulb categories.