Jeep J-3600 Back Up Light Bulb Size

The Jeep J-3600 back up light uses a 1073 or 1156 bulb size depending on the specific vehicle configuration. The replacement chart covers 1965 through 1968 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.

Bulb Size by Year Range

Years	Bulb Size
1968	1073
1965-1967	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-3600 backup light specifications cover the 1965-1968 model years, with two distinct bulb types appearing across that span.
The 1156 bulb is the more frequently specified type, fitting the 1965-1967 Jeep J-3600 backup lights across three consecutive model years.
The 1156 operates at 12 volts and draws 21 watts, making it a relatively high-output single-filament bulb for its class.
Both the 1156 and 1073 share the BA15s bayonet base, a single-contact base design that physically allows one bulb to seat in the other's socket.
Despite sharing the same BA15s base, the 1073 and 1156 are not interchangeable without consequence, as the 1073 runs at 13 watts versus the 1156's 21 watts, a significant difference in output.
The 1968 Jeep J-3600 specifies the 1073 bulb, which is the lower-wattage variant of the 1156 at 12 volts and 13 watts.
Both bulb types conform to ANSI standards recognized in the United States and Canada, indicating standardized electrical and physical tolerances.
The single-filament construction of both bulbs means each serves only one lighting function, with no secondary filament for a dual-purpose role such as combined stop and tail operation.