Chevrolet Brookwood Turn Signal Bulb Size

Chevrolet Brookwood front and rear turn signal bulbs utilize 1157 and 1034 bulb sizes across the vehicle's lighting system. The replacement chart covers 1958 through 1972 production years with corresponding bulb size specifications.

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

Front Turn Signal

If US Type and EU Type show the same value, a direct cross-reference for this bulb is not available or the data is insufficient.

Years	US Type	EU Type	Shop
1969-1972	1157	P21/5W	Check Price
1958-1961	1034	1034	Check Price

Rear Turn Signal

If US Type and EU Type show the same value, a direct cross-reference for this bulb is not available or the data is insufficient.

Years	US Type	EU Type	Shop
1969-1972	1157	P21/5W	Check Price
1958-1961	1034	1034	Check Price

Bulb Specifications

Description	Type	Shop
ANSI standard (US & Canada). Dual-filament bulb with BAY15d bayonet base. 12V, 21W/5W.	1157	Check Price
ECE standard (Europe & worldwide). Dual-filament signalling bulb with BAY15d bayonet base. 12V, 21W/5W.	P21/5W	Check Price
ANSI standard (US & Canada). Dual-filament bulb with BAY15d bayonet base. Variant of 1157. 12V, 21/5W.	1034	Check Price

Other Locations

Additional Notes

The 1157 bulb is an ANSI-standard dual-filament type operating at 12V with a 21W/5W output rating and a BAY15d bayonet base. It serves both front and rear turn signal positions on the Chevrolet Brookwood for the 1969-1972 model years.
The 1034 bulb shares the same BAY15d bayonet base, dual-filament construction, 12V operating voltage, and 21W/5W output as the 1157, and is classified as a variant of that type under the ANSI standard applicable in the US and Canada.
The 1034 bulb is specified for both the front and rear turn signal positions on the Brookwood for the 1958-1961 model years.
Both the 1157 and 1034 are recognized under the same ANSI framework and share identical base geometry and voltage ratings, yet they are listed as distinct part numbers, which indicates they are not directly interchangeable despite their similarities.
The dual-filament design of both bulb types allows a single housing to serve two separate electrical functions, typically combining a higher-wattage turn signal filament with a lower-wattage running or parking light filament within one unit.
The BAY15d bayonet base features two offset locating pins, a physical characteristic that prevents incorrect rotational insertion and distinguishes it from single-pin bayonet bases used in other automotive applications.