The Buick GS 455 front turn signal bulb size measures 1034NA or 1157NA, while the rear turn signal bulb size measures 1157. The replacement chart covers vehicle production years spanning 1970 to 1972 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 Buick GS 455 turn signal positions, appearing in both the front and rear turn signal roles for the 1970-1971 model years, as well as the rear turn signal for 1972.
All three bulb types listed in these specifications, the 1034NA, 1157NA, and 1157, share the BAY15d bayonet base, a double-contact offset-pin base standard that physically locks the bulb into position with a twist.
All three bulb types operate at 12 volts and carry a dual-filament design rated at 21W and 5W, where the higher wattage filament serves the active turn signal function and the lower wattage filament serves a parking or running light function.
The 1034NA and 1157NA are natural amber glass bulbs, meaning the amber color is produced by the glass envelope itself rather than by a coating or lens, which is a distinction relevant to light output consistency over time.
The 1034NA is described as a variant of the 1157, and while both share the BAY15d base and the same voltage and wattage ratings, they are not the same part number and are not listed as interchangeable without qualification in these specifications.
The front turn signal of the Buick GS 455 changed from the 1157NA in 1970-1971 to the 1034NA in 1972, representing a shift to a variant bulb in that position for the final listed model year.
The rear turn signal of the Buick GS 455 uses the clear-glass 1157 across all three listed model years, 1970-1972, without any variation in specification.
The 1157NA and 1034NA are both ANSI-standardized bulbs recognized in the United States and Canada, indicating conformance to a defined set of electrical and physical tolerances under that standard.