Ford Custom front and rear turn signal bulbs utilized 1157NA, 1034NA, 1157, 1034, and 1154 bulb sizes across different model configurations. The replacement chart covers 1950 through 1972 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.
The Ford Custom uses five distinct bulb types across its front and rear turn signal positions: 1157NA, 1034NA, 1157, 1034, and 1154, all of which share the BAY15d bayonet base and dual-filament construction.
The 1157NA and 1034NA bulbs are distinguished from their clear-glass counterparts by natural amber glass, which produces an amber signal output without relying on an amber lens.
The 1157 and 1157NA operate at 12V with a 21W high filament and a 5W low filament, a wattage split typical of dual-filament automotive bulbs where the lower filament serves as a running or parking light and the higher filament activates during signaling.
The 1034 and 1034NA are designated variants of the 1157, sharing the same 12V, 21W/5W ratings and BAY15d base, though they are listed as separate ANSI part numbers.
The 1154 is an older variant of the 1157 and is rated for both 6V and 12V operation, reflecting the transition-era electrical systems found in early 1950s vehicles.
The Ford Custom (1950-1952) uses the 1154 bulb in both front and rear turn signal positions, making it the only model year range in these specifications to require a 6V/12V-compatible bulb.
From 1964-1972, the rear turn signal position consistently uses the standard 1157 bulb across all listed years, while the front position varies between 1157NA and 1034NA depending on the year.
The 1969 Ford Custom front turn signal is the only instance within the 1964-1972 range where the front position uses the clear-glass 1157 rather than an NA-suffix amber variant.
The 1957 Ford Custom uses the 1034 in both front and rear turn signal positions, placing it between the 1154-era vehicles of the early 1950s and the predominantly NA-suffix front bulbs of the 1960s-1970s.
Because the 1157NA, 1034NA, 1157, and 1034 all share the BAY15d base and the same voltage and wattage ratings, physical fitment is compatible across these types, though substituting a clear-glass bulb for an NA variant may affect the amber color output if the lens is also clear.