Chevrolet C70 Turn Signal Bulb Size

The Chevrolet C70 front and rear turn signal bulbs utilize 1157 and 2057 sizes. The replacement chart covers vehicle production spanning 1960 to 1988.

The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.

Front Turn Signal

If US Type and EU Type show the same value, a direct cross-reference for this bulb is not available or the data is insufficient.

Years	US Type	EU Type	Shop
1985-1988	1157	P21/5W	Check Price
1984	2057	2057	Check Price
1979-1983	1157	P21/5W	Check Price
1960-1961	1157	P21/5W	Check Price

Rear Turn Signal

If US Type and EU Type show the same value, a direct cross-reference for this bulb is not available or the data is insufficient.

Years	US Type	EU Type	Shop
1985-1988	1157	P21/5W	Check Price
1983-1984	2057	2057	Check Price
1979-1982	1157	P21/5W	Check Price
1960-1961	1157	P21/5W	Check Price

Bulb Specifications

Description	Type	Shop
ANSI standard (US & Canada). Dual-filament bulb with BAY15d bayonet base. 12V, 21W/5W.	1157	Check Price
ECE standard (Europe & worldwide). Dual-filament signalling bulb with BAY15d bayonet base. 12V, 21W/5W.	P21/5W	Check Price
ANSI standard (US & Canada). Dual-filament bulb with BAY15d bayonet base. Brighter variant of 1157. 12V, 26.9W/8W.	2057	Check Price

Other Locations

Additional Notes

The 1157 bulb is the dominant turn signal specification across the Chevrolet C70, appearing in both front and rear positions for the majority of listed model years, including 1960-1961 and 1979-1983 (front), as well as 1985-1988 for both positions.
The 1157 is a dual-filament bulb rated at 12V with a 21W high-filament and 5W low-filament output, mounted on a BAY15d bayonet base, and standardized under ANSI specifications for the US and Canadian markets.
The 2057 bulb shares the same BAY15d bayonet base as the 1157 but operates at higher wattage, rated at 26.9W on the high filament and 8W on the low filament, making it the brighter of the two ANSI-standard types listed in these specifications.
The Chevrolet C70 (1984) is specified with the 2057 bulb in both the front and rear turn signal positions, distinguishing that year from the surrounding model years in the dataset.
The 1983 rear turn signal position is specified with the 2057 bulb, while the 1983 front turn signal position uses the 1157, indicating that front and rear fitments were not always identical within the same model year.
Although the 1157 and 2057 share the BAY15d bayonet base, the wattage difference between the two types is a relevant fitment consideration, as the 2057 draws more current on both filaments than the 1157.