Mack RM Tail Light Bulb Size
The Mack RM tail light utilizes a single 1157 bulb size for the rear illumination system across all listed vehicle applications. Available data covers a specific production range starting from 1981 through 1993.
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 |
|---|---|
| 1981-1993 | 1157 |
Bulb Specifications
| Description | Bulb Size |
|---|---|
| ANSI standard (US & Canada). Dual-filament bulb with BAY15d bayonet base. 12V, 21W/5W. | 1157 |