Chevrolet Sedan Delivery Back Up Light Bulb Size

Chevrolet Sedan Delivery back up light bulb sizes include 1156 and 1073, with each bulb size specified for particular model configurations. The replacement chart covers 1958 to 1960 production years and documents bulb specifications across the model range.

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
1960	1156
1959	1073
1958	1156

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 and 1073 are both ANSI-standardized bulb types used in the United States and Canada, each built around a single-filament design with a BA15s bayonet base.
The BA15s bayonet base uses a single contact pin, which physically distinguishes it from dual-pin bayonet bases and limits socket compatibility accordingly.
The 1156 operates at 12V and 21W, while the 1073 operates at 12V and 13W, meaning the two bulbs draw meaningfully different amounts of current despite sharing the same base type.
Because the 1073 is a lower-wattage variant of the 1156, the shared BA15s base does not make them interchangeable without accounting for the wattage difference, which affects output brightness and circuit load.
The Chevrolet Sedan Delivery used the 1156 for the 1958 and 1960 model years, and the 1073 exclusively for the 1959 model year.
The 1959 Chevrolet Sedan Delivery is the only year in this specification set fitted with the lower-wattage 1073 bulb, isolating it from the surrounding model years in terms of backup light output.
Substituting a 1156 into a socket specified for the 1073 would introduce a higher wattage load than the original circuit was designed around for the 1959 model year.