GMC F350 Dome Light Bulb Size

GMC F350 dome light bulb uses a 94 size specification. The replacement chart covers 1956 to 1957 production years with corresponding bulb size data.

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
1956-1957	94

Description	Bulb Size
ANSI standard (US & Canada). Dual-filament bulb with BAY15d bayonet base. Variant of 1157. 12V, 21/5W.	94

The GMC F350 (1956-1957) uses a size 94 bulb for the dome light.
The 94 bulb follows the ANSI standard, applicable in both the United States and Canada.
It is a dual-filament bulb, meaning it contains two separate filaments within a single envelope, each serving a distinct function.
The 94 bulb uses a BAY15d bayonet base, a two-pin offset bayonet mount where the two pins are positioned at different heights to ensure correct orientation during installation.
The 94 bulb operates at 12 volts with a wattage rating of 21/5W, corresponding to its high and low filaments respectively.
The 94 bulb is a variant of the 1157, a widely used automotive bulb type, indicating shared electrical and physical characteristics with that family of bulbs.