The Ford F-250 side marker uses 3157 and 916NA bulb sizes for the lighting components located on the exterior of the vehicle. Data for the specified lighting covers the range from 1995 through 1999.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The Ford F-250 front side marker uses two distinct bulb types across its model years: the 3157 and the 194. The 194 accounts for the majority of front side marker fitments in the specifications, covering 1972-1988 (excluding 1989-1991) as well as 1992-1996, while the 3157 appears in 1989-1991 and 1997-1999.
The 194 is a T10 miniature wedge bulb rated at 12V and 3.78W under the ANSI standard. Its single-filament, low-wattage design is typical of side marker and parking light applications where illumination rather than signaling is the primary function.
The 3157 is a T25 dual-filament wedge bulb rated at 12V with a 27W bright filament and a 7W dim filament. Its dual-filament construction means it is capable of serving both a steady marker function and a higher-intensity signal function, depending on how the vehicle's circuit is wired.
Because the 3157 and 194 are physically different bulb types with different wattage ratings and socket configurations, they are not interchangeable. The Ford F-250 front side marker socket type therefore differs between model year groups, and a replacement bulb must match the specific year being serviced.
The 1953-1955 Ford F-250 front and rear side markers share the same bulb: the 63, a single-filament bulb with a BA9s bayonet base rated at 12V and 0.63W. The BA9s base is a miniature bayonet fitting, distinct from the wedge-base designs used in later model years.
The rear side marker specifications show less consistency across years than the front. Four different bulb types appear in the rear side marker data: the 194, the 63, the 1157, and the 1895, each with a different base type and wattage rating.
The 1157 rear side marker bulb, listed for the 1987 Ford F-250, uses a BAY15d bayonet base and carries dual filaments rated at 21W and 5W at 12V. The BAY15d base is physically incompatible with wedge-base sockets, making the 1987 rear side marker socket distinct from surrounding model years that use the 194.
The 1895, listed for the 1980 rear side marker, is a T5 miniature wedge bulb rated at 12V and 0.9W. Although it shares a wedge-base form factor with the 194, the two bulbs differ in physical size and wattage, and they are not considered direct substitutes for one another.
All five bulb types in the specifications, the 3157, 194, 63, 1157, and 1895, are classified under the ANSI standard and are recognized in both the United States and Canada, indicating standardized electrical and physical specifications for each type.
The front and rear side markers on the 1988-1991 Ford F-250 use different bulb types from each other. The front uses the 3157 in 1989-1991 and the 194 in 1988, while the rear uses the 194 for all four years, meaning front and rear bulbs are not interchangeable during that period.