Ford Ranchero Dome Light Bulb Size

The Ford Ranchero dome light utilizes unique bulb sizes 161, 211-2, 1003, 561, and 105 depending on the specific production version. Data for the internal illumination components covers the span from 1957 through 1979.

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
1979	161
1978	211-2
1977	1003
1972-1976	561
1970-1971	105
1957-1969	1003

Bulb Specifications

Description	Bulb Size
ANSI standard (US & Canada). Miniature wedge bulb (T10). 12V, 1W.	161
ANSI standard (US & Canada). Festoon bulb, 41mm length, SV8.5 base. 12V, 12W.	211-2
ANSI standard (US & Canada). Single-filament bulb with BA15s bayonet base. 12V, 21W.	1003
ANSI standard (US & Canada). Festoon bulb, 44mm length, end-cap contacts. 12V, 12W.	561
ANSI standard (US & Canada). Single-filament bulb with BA15s bayonet base. Variant of 1156. 12V, 13W.	105

Other Locations

Additional Notes

The Ford Ranchero dome light specifications span model years 1957 through 1979, covering 23 years of production, with bulb requirements changing several times across that period.
The 1003 bulb is the most frequently specified across these years, covering the Ford Ranchero from 1957 through 1969 as well as 1977, making it the dominant fitment across this range.
The 1003 is a single-filament bulb with a BA15s bayonet base, rated at 12V and 21W, conforming to ANSI standards for both the US and Canadian markets.
The 561 festoon bulb is specified for the Ford Ranchero across 1972-1976. It measures 44mm in length and uses end-cap contacts rather than a bayonet or wedge base, operating at 12V and 12W.
The 211-2 festoon bulb, specified for the 1978 Ford Ranchero, shares the same 12V, 12W rating as the 561 but uses an SV8.5 base and measures 41mm in length, making the two festoon types physically incompatible with each other despite their similar wattage.
The 105 bulb, specified for 1970-1971, is a single-filament BA15s bayonet type rated at 12V and 13W. It is described as a variant of the 1156 family, though it draws notably less wattage than the 1003 bulb used in adjacent model years.
The 161 wedge bulb, specified for the 1979 Ford Ranchero, is a T10 miniature wedge type rated at just 1W, representing a significantly lower power draw than any other bulb type found across these specifications.
Because the BA15s bayonet base is shared between the 1003 and the 105, the two bulbs use the same socket type, though their wattage ratings differ at 21W and 13W respectively, and they are not listed as interchangeable within these specifications.
Each of the five bulb types listed conforms to ANSI standards applicable in both the United States and Canada, indicating consistent regulatory compliance across all specified model years.
The base type changes across the production span from bayonet (BA15s) in earlier and mid-period years, to festoon end-cap and SV8.5 configurations in the mid-to-late 1970s, and finally to a wedge base in 1979, reflecting distinct socket requirements for each fitment group.