GMC 300 Turn Signal Bulb Size
GMC 300 front turn signal bulbs utilize 1073 or 1129 size specifications, while rear turn signal bulbs use 1073, 1156, or 1129 sizes. The replacement chart covers 1951 through 1959 production years 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 Type | Shop |
|---|---|---|
| 1956-1959 | 1073 | Check Price |
| 1951-1955 | 1129 | 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 |
|---|---|---|---|
| 1959 | 1073 | 1073 | Check Price |
| 1958 | 1156 | P21W | Check Price |
| 1956-1957 | 1073 | 1073 | Check Price |
| 1951-1955 | 1129 | 1129 | Check Price |
Bulb Specifications
| Description | Type | Shop |
|---|---|---|
| ANSI standard (US & Canada). Single-filament bulb with BA15s bayonet base. Lower wattage variant of 1156. 12V, 13W. | 1073 | Check Price |
| ANSI standard (US & Canada). Dual-filament bulb with BAY15d bayonet base. Variant of 1157. 12V, 21/5W. | 1129 | Check Price |
| ANSI standard (US & Canada). Single-filament bulb with BA15s bayonet base. 12V, 21W. | 1156 | Check Price |
| ECE standard (Europe & worldwide). Single-filament signalling bulb with BA15s bayonet base. 12V, 21W. | P21W | Check Price |