GMC R2500 Courtesy Bulb Size
The GMC R2500 courtesy light requires 1003 or 168 bulb sizes depending on the specific application. Data for 1003 and 168 bulbs covers the range from 1987 to 1989.
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 |
|---|---|
| 1988-1989 | 1003 |
| 1987 | 168 |
Bulb Specifications
| Description | Bulb Size |
|---|---|
| ANSI standard (US & Canada). Single-filament bulb with BA15s bayonet base. 12V, 21W. | 1003 |
| ANSI standard (US & Canada). Miniature wedge bulb (T10). 12V, 4.9W. | 168 |