GMC G25 Turn Signal Bulb Size
The GMC G25 front and rear turn signal bulb sizes include 198, 199, 1156, and 1073 options, with the front position utilizing 198, 199, or 1156 bulbs and the rear position utilizing 198, 1156, or 1073 bulbs. The replacement chart covers vehicle production years from 1967 through 1978, detailing bulb specifications across the entire production span.
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 |
|---|---|---|---|
| 1973-1978 | 198 | 198 | Check Price |
| 1971-1972 | 199 | 199 | Check Price |
| 1968-1970 | 1156 | P21W | Check Price |
| 1967 | 1034 | 1034 | 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 |
|---|---|---|---|
| 1973-1978 | 198 | 198 | Check Price |
| 1969-1972 | 1156 | P21W | Check Price |
| 1967-1968 | 1073 | 1073 | Check Price |
Bulb Specifications
| Description | Type | Shop |
|---|---|---|
| ANSI standard (US & Canada). Miniature wedge bulb (T5). 12V, 2W. | 198 | Check Price |
| ANSI standard (US & Canada). Single-filament bulb with BA15s bayonet base. Variant of 1156. 12V, 21W. | 199 | 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 |
| ANSI standard (US & Canada). Dual-filament bulb with BAY15d bayonet base. Variant of 1157. 12V, 21/5W. | 1034 | Check Price |
| ANSI standard (US & Canada). Single-filament bulb with BA15s bayonet base. Lower wattage variant of 1156. 12V, 13W. | 1073 | Check Price |