Ford E-300 Back Up Light Bulb Size

The Ford E-300 back up light bulb uses 2 distinct sizes: 1156 and 199. The replacement chart covers vehicle production years spanning 1972 to 1974.

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
1973-1974	1156
1972	199

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. Variant of 1156. 12V, 21W.	199

The Ford E-300 back up light specifications cover model years 1972-1974, with two distinct bulb types appearing across that range.
The 1156 is the bulb type fitted to the 1973-1974 Ford E-300 back up lights.
The 1156 is an ANSI-standard single-filament bulb rated at 12V and 21W, using a BA15s bayonet base.
A BA15s bayonet base is a single-contact bayonet fitting, meaning the bulb locks into its socket with a twist rather than a screw thread.
The 1972 Ford E-300 uses the 199 bulb type for the back up light position.
The 199 is also an ANSI-standard single-filament bulb rated at 12V and 21W with a BA15s bayonet base, and it is classified as a variant of the 1156.
Despite the 199 being a variant of the 1156, the two are listed under separate part numbers in the specifications, which is relevant to fitment decisions for the respective model years.
Both the 1156 and 199 share identical electrical ratings of 12V and 21W, as well as the same BA15s base type.