The Ford E-100 front turn signal requires bulbs in sizes 1034NA, 1157NA, or 1157, while the rear turn signal uses either 1157 or 198 bulb sizes. The replacement chart covers 1969 through 1983 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 1157 bulb is the most frequently specified type across the Ford E-100 turn signal data, appearing in both front and rear positions across multiple model years. It is an ANSI-standard dual-filament bulb with a BAY15d bayonet base, rated at 12V and 21W/5W.
The BAY15d bayonet base is shared by the 1157, 1157NA, and 1034NA bulbs. All three carry the same 12V, 21W/5W rating, meaning the two filaments serve separate functions, typically running light and turn or brake signal duties.
The 1157NA and 1034NA variants differ from the standard 1157 in that their glass envelope is natural amber rather than clear. This shifts the color filtering from the lens to the bulb itself.
The 1034NA is described as a variant of the 1157, sharing the same BAY15d base and 12V, 21W/5W rating. Despite this relationship, the two are listed as distinct part numbers and are not presented as interchangeable in the specifications.
The Ford E-100 front turn signal for 1969-1972 uses the 198 bulb, a miniature wedge type rated at 12V and 2W. This is a single-filament bulb with significantly lower wattage than the dual-filament types used in later years.
The rear turn signal for the Ford E-100 also uses the 198 bulb for 1969-1972, matching the front position during those years. From 1973 onward, the rear position transitions to the 1157, while the front position follows a different pattern.
The front and rear turn signal bulb sizes diverge for 1973 and 1983. In those years, the front position uses the 1034NA while the rear uses the 1157, indicating the two positions are not served by the same bulb in those model years.
For 1974-1982, the front turn signal of the Ford E-100 uses either the 1157NA or 1157, both of which share the BAY15d base and identical wattage ratings. The physical base compatibility does not confirm interchangeability, as the amber glass coating on the NA variants affects light output color.
The 198 bulb is a T5 wedge type, which uses a different mounting method than the BAY15d bayonet base. The two base types are physically incompatible, meaning 1969-1972 sockets cannot accept the 1157-series bulbs used in later model years without modification.
Across all listed years, the rear turn signal of the Ford E-100 uses only two bulb types: the 198 for 1969-1972 and the 1157 for 1973-1983. The front position, by contrast, uses four distinct bulb designations across the same span.