The Oldsmobile 442 front turn signal bulb accommodates 3 distinct sizes including 1157NA, 1034NA, and 1157, while the rear turn signal bulb uses a 1157 size. The replacement chart covers vehicle production years spanning 1964 to 1971.
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 widely used type across the Oldsmobile 442 turn signal specifications, appearing in the rear turn signal position for all model years from 1964-1971 and in the front turn signal position for 1964-1967, 1969, and 1971.
All three bulb types listed in the Oldsmobile 442 turn signal specifications, the 1157, 1157NA, and 1034NA, share the same BAY15d bayonet base and the same 12V, 21W/5W dual-filament electrical ratings.
The BAY15d bayonet base is a two-pin offset base design, where the two pins are positioned at different heights along the base to ensure correct orientation during installation.
The dual-filament construction of all three bulb types serves two functions within a single housing: the higher-wattage 21W filament operates as the turn signal, while the lower-wattage 5W filament serves as a running or parking light.
The 1157NA and 1034NA variants differ from the standard 1157 by the inclusion of natural amber glass, which produces an amber-colored output without relying on an amber-tinted lens.
The 1034NA is described as a variant of the 1157, and while it shares the same base type and voltage and wattage ratings, it is a distinct ANSI part number and is not listed as a direct substitute for the 1157NA in these specifications.
The Oldsmobile 442 front turn signal position alternates between the 1157NA and the 1034NA across certain model years, with 1034NA specified for 1968 and 1970, and 1157NA specified for 1967, 1969, and 1971.
The front and rear turn signal positions of the Oldsmobile 442 use matching bulb types only in years where the front position calls for the standard 1157, specifically 1964-1966, as the rear position consistently uses the 1157 throughout all listed years.