GMC General Turn Signal Indicator Bulb Size
The GMC General turn signal indicator uses bulb sizes 158 and 57 for the lighting components. Data for the specific bulbs covers the range from 1984 to 1988.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
Bulb Size by Year Range
| Years | Bulb Size |
|---|---|
| 1988 | 158 (Tiltmaster) |
| 1986-1987 | 57 (Tiltmaster) |
| 1984-1985 | 158 (Tiltmaster) |
Bulb Specifications
| Description | Bulb Size |
|---|---|
| ANSI standard (US & Canada). Miniature wedge bulb (T10). 12V, 3W. | 158 |
| ANSI standard (US & Canada). Single-filament bulb with BA9s base. 12V, 1W. | 57 |