GMC C1500 Suburban License Plate Bulb Size

The GMC C1500 Suburban license plate light uses 194 and 67 bulb sizes according to the provided technical data. Information covers the period from 1979 through 1999 for the specified vehicle components.

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 C1500 Suburban uses two distinct bulb types for the license plate position across its model years: the 194 and the 67.
The 194 bulb is a T10 miniature wedge type 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 bulb operates at 12 volts and 8 watts, features a BA15s single-contact bayonet base, and is classified as a lower wattage variant of the 1156 bulb family.
Because the 194 uses a wedge base and the 67 uses a BA15s bayonet base, the two bulb types are physically incompatible and are not interchangeable with each other.
The 1992-1999 GMC C1500 Suburban models take the 194 bulb for the license plate position.
The 1979-1986 GMC C1500 Suburban models take the 67 bulb for the license plate position.
The wattage difference between the two bulbs is notable: the 67 at 8 watts draws more than twice the power of the 194 at 3.78 watts, reflecting a generational shift in automotive lighting toward lower-consumption components.
Both the 194 and the 67 conform to ANSI standards, meaning they are produced by multiple manufacturers to a consistent specification across the US and Canadian markets.
The BA15s designation on the 67 bulb indicates a single-contact bayonet cap with a 15mm base width, a fitting also found on various other automotive and general-purpose bulb applications.