GMC K2500 License Plate Bulb Size

The GMC K2500 license plate light uses 194 and 67 bulb sizes depending on the specific production period for the vehicle. Provided information covers the span from 1979 through 2000 for the listed 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
1988-2000	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 K2500 uses two distinct bulb types for the license plate position across its model years: the 194 and the 67.
The 194 bulb is the license plate bulb for the GMC K2500 spanning the 1988-2000 model years.
The 67 bulb applies to the 1979-1986 model years of the K2500 for the same license plate position.
The 194 is a T10 miniature wedge bulb rated at 12V and 3.78W, conforming to ANSI standards recognized in both the US and Canada.
The wedge base of the 194 bulb relies on the tension of its contacts rather than a locking mechanism, which distinguishes it from bayonet-style bulbs.
The 67 bulb uses a BA15s single-contact bayonet base, operates at 12V, and draws 8W, making it notably higher in wattage than the 194.
The 67 is a single-filament bulb and is considered a lower-wattage variant of the 1156, sharing the same BA15s base but not the same wattage rating, so the two are not interchangeable without consideration of the wattage difference.
Because the 194 uses a wedge base and the 67 uses a bayonet base, the two bulb types are physically incompatible with each other's sockets, and substitution between the two model year groups is not possible without socket modification.