GMC C15 Turn Signal Bulb Size
The GMC C15 front turn signal bulb size includes 198, 1156, and 199 options, while the rear turn signal bulb size encompasses 198, 1156, and 1073 specifications. The replacement chart covers vehicle production years from 1967 through 1978 with corresponding bulb size data.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
Front Turn Signal
| Years | Bulb Size |
|---|---|
| 1973-1978 | 198 |
| 1970-1972 | 1156 |
| 1969 | 199 |
| 1968 | 1073 |
| 1967 | 1034 |
Rear Turn Signal
| Years | Bulb Size |
|---|---|
| 1973-1978 | 198 |
| 1969-1972 | 1156 |
| 1967-1968 | 1073 |
Bulb Specifications
| Description | Bulb Size |
|---|---|
| ANSI standard (US & Canada). Miniature wedge bulb (T5). 12V, 2W. | 198 |
| ANSI standard (US & Canada). Single-filament bulb with BA15s bayonet base. 12V, 21W. | 1156 |
| ANSI standard (US & Canada). Single-filament bulb with BA15s bayonet base. Variant of 1156. 12V, 21W. | 199 |
| ANSI standard (US & Canada). Single-filament bulb with BA15s bayonet base. Lower wattage variant of 1156. 12V, 13W. | 1073 |
| ANSI standard (US & Canada). Dual-filament bulb with BAY15d bayonet base. Variant of 1157. 12V, 21/5W. | 1034 |