GMC G2500 License Plate Bulb Size

The GMC G2500 license plate light uses bulb size 194 and bulb size 67 for the various lighting components located on the rear of the vehicle. Available data for the lighting specifications covers the range from 1979 through 1995 for the specified automotive application.

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
1995	194
1979-1994	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 G2500 license plate bulb specifications cover model years 1979 through 1995.
Two bulb types appear across these model years: the 194 and the 67, both of which conform to ANSI standards recognized in the United States and Canada.
The bulb 67 is specified for the GMC G2500 across model years 1979-1994, making it the predominant license plate bulb across this vehicle's documented history.
The 67 bulb uses a BA15s single-contact bayonet base, a base type that requires a twist-and-lock installation rather than a wedge-style insertion.
At 12V and 8W, the 67 bulb operates at a higher wattage than the 194, which draws only 3.78W at the same voltage.
The 67 bulb is a lower-wattage variant of the 1156 bulb. Although both share the BA15s bayonet base, the 1156 operates at a higher wattage, and the two are not interchangeable without accounting for that difference.
For the 1995 model year, the specification shifts to the 194 bulb, a T10 miniature wedge type rated at 12V and 3.78W.
The T10 wedge base of the 194 bulb is physically incompatible with the BA15s bayonet socket used by the 67 bulb, meaning the two types cannot be substituted for one another in their respective sockets.