GMC C2500 Suburban License Plate Bulb Size

The GMC C2500 Suburban license plate light requires bulb sizes 194 and 67 depending on the specific production period. Data for the lighting components covers the range from 1979 to 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
1992-1999	194
1979-1986	67

Bulb Specifications

Description	Bulb Size
ANSI standard (US & Canada). Miniature wedge bulb (T10). 12V, 3.78W.	194
ANSI standard (US & Canada). Single-filament bulb with BA15s bayonet base. Lower wattage variant of 1156. 12V, 8W.	67

Other Locations

Additional Notes

The GMC C2500 Suburban uses two distinct bulb types for the license plate position across its model years: the 194 for 1992-1999 and the 67 for 1979-1986.
The 194 is a T10 miniature wedge bulb rated at 12 volts and 3.78 watts, conforming to ANSI standards recognized in both the United States and Canada.
The wedge base design of the 194 means it is held in place by tension from the socket itself, with no separate locking mechanism such as a bayonet or screw fitting.
The 67 is a single-filament bulb rated at 12 volts and 8 watts, fitted with a BA15s bayonet base, and also carries ANSI standardization for the US and Canadian markets.
The BA15s bayonet base of the 67 features a single locating pin, which distinguishes it from dual-pin bayonet variants and makes it non-interchangeable with those types.
The 67 is described as a lower wattage variant of the 1156, meaning the two bulbs share the same BA15s base but draw different amounts of power, making them physically compatible at the socket while differing in output.
The 194 draws considerably less power than the 67, at 3.78 watts versus 8 watts, reflecting a difference in the electrical load each places on the vehicle's circuit.
Because the 194 uses a wedge base and the 67 uses a bayonet base, the two bulb types are not interchangeable with each other regardless of voltage compatibility.