Ford Ranch Wagon Back Up Light Bulb Size

The Ford Ranch Wagon back up light uses 1156, P21W, 1141, and 1129 bulb sizes. Data for the provided components covers the range from 1953 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
1965-1974	1156
1963-1964	1141
1959-1962	1156
1956-1958	1141
1953-1955	1129

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. 12V, 21W.	1141
ANSI standard (US & Canada). Dual-filament bulb with BAY15d bayonet base. Variant of 1157. 12V, 21/5W.	1129

Other Locations

Additional Notes

The Ford Ranch Wagon uses two bulb types across its back up light specifications: the 1156 and 1141, both of which are single-filament bulbs rated at 12V and 21W with a BA15s bayonet base.
The 1156 and 1141 share identical electrical ratings of 12V and 21W, and both use the BA15s bayonet base, which is a single-contact base with a single locating pin.
Despite their shared electrical and physical characteristics, the 1156 and 1141 are distinct ANSI-standard part numbers, and their interchangeability is not confirmed by the specifications.
The Ford Ranch Wagon (1965-1974) uses the 1156 bulb for the back up light across all ten model years in that range.
The 1963-1964 model years specify the 1141 bulb, while the surrounding years of 1959-1962 and 1965 onward specify the 1156, indicating a mid-production bulb type change.
The 1953-1955 model years specify the 1129 bulb, which is a dual-filament unit rated at 12V and 21/5W, using a BAY15d bayonet base rather than the BA15s base found on the 1156 and 1141.
The BAY15d base of the 1129 features two filaments and an offset locating pin, making it physically incompatible with sockets designed for the single-filament BA15s base used by the 1156 and 1141.
The 1129 is noted as a variant of the 1157, a widely recognized dual-filament automotive bulb, though the 1129 retains its own distinct ANSI designation.
All three bulb types specified across the Ford Ranch Wagon back up light fitments are ANSI standards recognized in both the United States and Canada.
The 1956-1958 model years specify the 1141 bulb, and the 1959-1962 model years return to the 1156, reflecting two separate bulb type transitions within the pre-1963 production span.