Chevrolet B60 Turn Signal Bulb Size

Additional Notes

• The 1157 is a dual-filament bulb operating at 12 volts with a BAY15d bayonet base, rated at 21W on the high filament and 5W on the low filament. It meets ANSI standards for the US and Canada.
• The 2057 shares the same 12-volt BAY15d bayonet base as the 1157 but draws more power, rated at 26.9W on the high filament and 8W on the low filament, making it the higher-output of the two bulb types used across these specifications.
• Because both the 1157 and 2057 use the same BAY15d bayonet base, they are physically interchangeable in the socket. However, the difference in wattage ratings means the two types are not electrically equivalent, and substituting one for the other may affect turn signal brightness or circuit behavior.
• The Chevrolet B60 front and rear turn signals use identical bulb sizes for each model year, meaning the same bulb type applies to both positions in any given year.
• The 1157 bulb is specified for the 1980-1982 and 1985-1991 model years across both front and rear turn signal positions.
• The 2057 bulb is specified for the 1983-1984 model years in both the front and rear turn signal positions.