Jeep J-3800 Back Up Light Bulb Size

The Jeep J-3800 back up light uses 1073 and 1156 bulb sizes for this model. The replacement chart covers vehicle production years spanning 1965 to 1968 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
1968	1073
1967	1156
1966	1073
1965	1156

Bulb Specifications

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

Other Locations

Additional Notes

The Jeep J-3800 backup light specifications cover model years 1965 through 1968, with two different bulb sizes used across those years.
Both bulb types specified for the Jeep J-3800, the 1073 and the 1156, follow ANSI standards recognized in the US and Canada.
The 1073 and 1156 share the same BA15s bayonet base, a single-contact base design where a pin on one side locks the bulb into the socket with a push-and-twist motion.
Both bulbs operate at 12 volts and use a single filament, meaning neither supports dual-intensity functions such as combined stop and tail operation.
The 1073 is rated at 13 watts, while the 1156 is rated at 21 watts, making the 1156 a notably higher-output bulb despite sharing the same base type as the 1073.
The 1073 is described as a lower wattage variant of the 1156, and while the two bulbs share a physically compatible BA15s base, the wattage difference means they are not functionally interchangeable without affecting light output.
The J-3800 used the 1156 in 1965 and 1967, and the 1073 in 1966 and 1968, indicating the specified bulb size alternated between model years rather than following a single consistent fitment across the production run.