Chevrolet Brookwood Back Up Light Bulb Size

The Chevrolet Brookwood back up light utilizes 1073, 1156, and P21W bulb sizes depending on the specific production period. Data for the provided bulb sizes covers the range from 1958 to 1972.

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
1969-1972	1156
1960-1961	1156
1958-1959	1073

Bulb Specifications

Description	Bulb Size
ANSI standard (US & Canada). Single-filament bulb with BA15s bayonet base. 12V, 21W.	1156
ANSI standard (US & Canada). Single-filament bulb with BA15s bayonet base. Lower wattage variant of 1156. 12V, 13W.	1073

Other Locations

Additional Notes

The 1156 bulb is an ANSI-standardized single-filament type rated at 12 volts and 21 watts, fitted with a BA15s bayonet base, and recognized across both the United States and Canada.
The 1073 bulb shares the same BA15s bayonet base and 12-volt operating voltage as the 1156 but draws only 13 watts, making it a lower-wattage variant within the same base family.
The Chevrolet Brookwood used the 1156 bulb for its back up lights across the 1960-1961 and 1969-1972 model years.
The 1958-1959 Brookwood used the 1073 bulb for its back up lights rather than the 1156.
Although the 1073 and 1156 share the same BA15s bayonet base, their wattage ratings differ by 8 watts, meaning the two types are not electrically interchangeable despite their physical base compatibility.
The BA15s designation indicates a single-contact bayonet base with a 15mm collar, a widely used format in automotive lighting applications of that era.