Plymouth Valiant front turn signal bulbs utilized 1034NA, 1157NA, and 1034 sizes, while rear turn signal bulbs used 1157 and 1034 sizes. The replacement chart covers 1960 to 1976 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 1034 and 1157 bulb types are the two most frequently specified across all turn signal positions on the Plymouth Valiant. Both are dual-filament bulbs rated at 12V with a 21W/5W power draw, and both use a BAY15d bayonet base. The higher wattage filament handles the turn signal function, while the lower wattage filament serves as a running or parking light.
The 1034NA and 1157NA designations are amber glass variants of the 1034 and 1157 respectively. The "NA" suffix indicates natural amber glass, meaning the color is produced by the glass envelope itself rather than by an external lens or coating.
All four bulb types specified for the Plymouth Valiant share the BAY15d bayonet base. This base type features two offset pins at different heights, which prevents incorrect insertion and ensures the dual filaments align properly within the socket.
Because the 1034 and 1034NA share the same base, wattage, and filament configuration, the only practical difference between them is the amber glass of the NA variant. The same relationship holds between the 1157 and 1157NA.
The front turn signal on the Plymouth Valiant used the 1034NA for most of its production run, specifically across 1960-1968, 1970-1972, and 1974-1976. The 1157NA appeared in the front position only during 1969, 1973, and 1975.
The rear turn signal specification shifted from the 1034 to the 1157 starting with the 1969 model year, and the 1157 remained the rear specification through 1976. Prior to 1969, the rear position used the 1034 across all listed model years from 1960-1968.
The earliest model years listed, 1960-1965, used the base 1034 designation without the NA suffix in the front turn signal position. From 1966 onward, the front specification shifted to the 1034NA, indicating a transition to amber glass bulbs in that position.
The rear turn signal used the base 1034 designation without the NA suffix from 1960-1968, and then transitioned to the base 1157 without the NA suffix from 1969-1976, meaning the rear position never carried an NA-designated bulb across any listed year.
Substituting a clear-glass 1034 or 1157 for an NA-designated position would affect the color output at the lens, since the amber tint would then depend entirely on any amber coloring present in the housing lens rather than the bulb itself.
Despite the 1034 being described as a variant of the 1157, the two are not listed interchangeably within the same model year and position on the Plymouth Valiant, indicating that the specific designation for each year and position is distinct.