GMC K2500 Suburban Courtesy Bulb Size
The GMC K2500 Suburban courtesy bulb utilizes 3 distinct sizes: 561, 74, and 1003 bulb configurations. The replacement chart documents vehicle production data spanning from 1979 through 1999.
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 |
|---|---|
| 1999 | 561 |
| 1998 | 74 |
| 1997 | 1003 |
| 1996 | 194 |
| 1994-1995 | 168 |
| 1993 | 194 |
| 1992 | 168 |
| 1985-1986 | 168 |
| 1984 | 1004 |
| 1983 | 1003 |
| 1979-1980 | 1156 |
Bulb Specifications
| Description | Bulb Size |
|---|---|
| ANSI standard (US & Canada). Festoon bulb, 44mm length, end-cap contacts. 12V, 12W. | 561 |
| ANSI standard (US & Canada). Miniature wedge bulb (T5). 12V, 1.4W. | 74 |
| ANSI standard (US & Canada). Single-filament bulb with BA15s bayonet base. 12V, 21W. | 1003 |
| ANSI standard (US & Canada). Miniature wedge bulb (T10). 12V, 3.78W. | 194 |
| ANSI standard (US & Canada). Miniature wedge bulb (T10). 12V, 4.9W. | 168 |
| ANSI standard (US & Canada). Dual-filament bulb with BAY15d bayonet base. Variant of 1157. 12V, 21/5W. | 1004 |
| ANSI standard (US & Canada). Single-filament bulb with BA15s bayonet base. 12V, 21W. | 1156 |