Chevrolet Del Ray Back Up Light Bulb Size

The Chevrolet Del Ray back up light requires a 1156 or 1073 bulb size for proper illumination. The replacement chart covers 1957 to 1958 vehicle production years with corresponding bulb specifications.

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
1958	1156
1957	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 operating at 12 volts and 21 watts, fitted with a BA15s bayonet base. It serves as the back up light bulb in the 1958 Chevrolet Del Ray.
The 1073 bulb shares the same ANSI-standardized BA15s bayonet base and 12-volt operating voltage as the 1156, but draws only 13 watts, making it a lower-output variant of that bulb type.
The BA15s designation indicates a single-contact bayonet base with a 15mm collar, a common automotive base format that physically accepts bulbs of differing wattage ratings within the same socket.
Despite the physical interchangeability that the shared BA15s base suggests, the 1957 Chevrolet Del Ray specifies the 1073 at 13W, while the 1958 model specifies the 1156 at 21W, representing a notable difference in rated output between the two model years.
Substituting a higher-wattage bulb such as the 1156 into a socket designed for the lower-wattage 1073 carries a risk of exceeding the thermal tolerances of the socket, wiring, or lens assembly in the 1957 application.