Chevrolet Chevy II front and rear turn signal bulbs utilized 1157 and 1034 bulb sizes across the vehicle's production span. The replacement chart contains specifications covering 1962 to 1968 model years.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The 1157 is an ANSI-standard dual-filament bulb rated at 12V with a 21W high filament and a 5W low filament, mounted on a BAY15d bayonet base. This two-filament design allows a single bulb to serve both turn signal and running light functions simultaneously.
The 1034 shares the same BAY15d bayonet base and 12V/21W/5W electrical ratings as the 1157 and is classified as a variant of it under the ANSI standard. Both are recognized across the US and Canada.
The BAY15d base type features two offset pins at different heights on the base collar. This offset pin arrangement is a physical keying mechanism that controls insertion orientation, preventing incorrect installation.
The Chevrolet Chevy II used the 1034 bulb in both the front and rear turn signal positions for the 1962-1963 model years.
Starting with the 1964 model year, the Chevy II transitioned to the 1157 bulb for both front and rear turn signals, a specification that remained consistent through 1968.
Because the 1034 and 1157 share the BAY15d base and identical voltage and wattage ratings, the physical and electrical differences between them are relevant to fitment. Despite their similarities, the 1034 is a variant rather than a direct equivalent, and the two are not formally listed as interchangeable within these specifications.
The front and rear turn signal positions on the Chevy II used identical bulb sizes in every model year covered by these specifications, meaning no distinction in bulb type existed between the front and rear circuits for any given year.