The Cadillac Brougham brake light uses 2057 and 3057 bulb sizes depending on the specific version of the vehicle. The provided data covers a range from 1987 through 1992.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The Cadillac Brougham uses two distinct bulb types across its brake light positions: dual-filament bulbs for the standard brake lights and a single-filament bulb for the center high mount stop light.
The 3057 and 2057 are both dual-filament bulbs, meaning each serves two lighting functions from a single housing, typically combining stop light and tail light operation within one unit.
The Cadillac Brougham (1990-1992) uses the 3057 bulb for the standard brake lights, while the 1987-1989 model years use the 2057 bulb in the same position.
The 3057 is a T25 wedge-type bulb, which uses a plastic wedge base rather than a metal bayonet fitting, making it physically incompatible with sockets designed for bayonet-base bulbs.
The 2057 uses a BAY15d bayonet base and is noted as a brighter variant of the 1157, though the two are not directly interchangeable due to differences in wattage and pin offset configurations.
Because the 3057 uses a wedge base and the 2057 uses a BAY15d bayonet base, these two bulbs are not interchangeable despite both serving the same brake light function across different model years.
The 1156 is a single-filament bulb with a BA15s bayonet base rated at 12V and 21W, and it serves exclusively as the center high mount stop light bulb across all Brougham model years covered in the specifications.
The BA15s base of the 1156 differs from the BAY15d base of the 2057 in pin alignment, which prevents substitution between the two bulb types even though both use bayonet-style bases.
All three bulb types conform to ANSI standards applicable in both the United States and Canada, indicating consistent electrical and physical specifications across those markets.
The center high mount stop light position uses the 1156 bulb consistently across all six model years from 1987-1992, while the standard brake light position transitions between two different bulb types over the same period.