GMC C3500HD License Plate Bulb Size

The GMC C3500HD license plate light requires a 194 bulb size for proper illumination of the rear vehicle area. Data for the specified component covers the period from 1991 through 2002.

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
1991-2002	194

Bulb Specifications

Description	Bulb Size
ANSI standard (US & Canada). Miniature wedge bulb (T10). 12V, 3.78W.	194

Other Locations

Additional Notes

The GMC C3500HD uses the 194 bulb for its license plate lighting across all listed model years, spanning 1991-2002.
The 194 is an ANSI-standardized bulb type recognized across the United States and Canada, meaning it conforms to a defined set of electrical and physical specifications shared by multiple manufacturers.
The 194 bulb follows the T10 wedge form factor, a miniature wedge-base design that seats by friction rather than by a twist-lock or bayonet mechanism.
The T10 designation refers to the bulb's tubular shape, with the number indicating a width of 10 eighths of an inch, a standard sizing convention used in North American bulb nomenclature.
The 194 operates at 12 volts and draws 3.78 watts, placing it in the low-wattage category typical of auxiliary lighting functions such as license plate illumination.
Because the 194 is an ANSI-standardized type, it is produced by numerous manufacturers and is broadly interchangeable at the bulb level, provided the replacement unit meets the same voltage and wattage ratings.