The American Motors Gremlin front turn signal bulb size measures 1157 or 1034NA, while the rear turn signal bulb size measures 1157. The replacement chart covers 1970 through 1978 vehicle 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 is the dominant bulb type across these specifications, appearing in both the front and rear turn signal positions for the American Motors Gremlin across model years 1971-1978, as well as the rear position in 1970.
The 1157 is an ANSI-standard dual-filament bulb rated at 12V with a 21W high filament and a 5W low filament, which allows it to serve both turn signal and parking light functions from a single unit.
The 1157 uses a BAY15d bayonet base, a two-pin offset base design that prevents incorrect installation by ensuring only one rotational orientation fits the socket.
The 1034NA is specified for the front turn signal position on the 1970 Gremlin only, while the rear turn signal for that same year uses the standard 1157.
The 1034NA shares the same BAY15d bayonet base and 12V, 21W/5W electrical ratings as the 1157, making it a variant of that bulb rather than a distinct type.
The distinguishing feature of the 1034NA is its natural amber glass envelope, which produces an amber signal output directly from the bulb rather than relying on a colored lens to filter white light.
Both the 1157 and 1034NA carry ANSI standardization applicable to the United States and Canada, indicating conformance to a shared North American specification.
Because the 1034NA and 1157 share the same base type and voltage and wattage ratings, a socket designed for one will physically accept the other, though the amber tint of the 1034NA affects the color output at the lens.