The Subaru DL front and rear turn signal bulb sizes include 1156, 1157, and 1034 options. The replacement chart covers vehicle production years spanning 1975 to 1989.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The 1156 bulb is the most frequently specified type across the Subaru DL turn signal data, covering both front and rear positions for the 1982-1989 model years, as well as the rear position for 1980-1981.
The 1156 is a single-filament bulb rated at 12V and 21W, fitted with a BA15s bayonet base, and produced to the ANSI standard used in the United States and Canada.
The 1157 bulb is a dual-filament type rated at 12V with a 21W main filament and a 5W secondary filament, using a BAY15d bayonet base. It serves both front and rear positions on the Subaru DL for the 1976-1978 model years, and the front position for 1979-1981.
The BAY15d base of the 1157 is offset-pin, meaning its two pins sit at different heights to prevent incorrect installation. This is a key physical distinction from the single-pin BA15s base of the 1156.
Because the 1156 and 1157 share a similar bayonet-style base but differ in pin configuration and filament count, the two types are not interchangeable.
The 1034 bulb is specified for both the front and rear turn signal positions on the 1975 Subaru DL. It is a dual-filament bulb rated at 12V and 21/5W, also using a BAY15d bayonet base.
The 1034 is noted as a variant of the 1157. Both share the BAY15d base and the same 21/5W filament ratings, though they are distinct ANSI part numbers and are not guaranteed to be interchangeable without confirming socket and application compatibility.
All three bulb types specified across the Subaru DL turn signal data operate on a 12V electrical system, consistent with standard automotive voltage.
The front turn signal position on the Subaru DL transitioned from the 1157 to the 1156 between the 1981 and 1982 model years, representing a shift from a dual-filament to a single-filament bulb in that location.
The rear turn signal position on the Subaru DL made the same 1157-to-1156 transition one model year earlier, between 1979 and 1980, resulting in a period from 1980 to 1981 where the front and rear positions required different bulb types.