GMC G3500 Map Light Bulb Size

The GMC G3500 map light utilizes a 906 bulb size for illumination within the interior cabin area. Available data for the specified component covers the range from 1985 through 1996.

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
1992-1996	906
1985-1987	906

Bulb Specifications

Description	Bulb Size
ANSI standard (US & Canada). Miniature wedge bulb (T10). 12V, 8W.	906

Other Locations

Additional Notes

The GMC G3500 uses the 906 bulb size across all listed model years for the map light position.
The years covered by these specifications are 1985-1987 and 1992-1996.
The 906 is an ANSI-standardized bulb type, meaning its specifications are governed by a recognized North American standard applicable in both the United States and Canada.
It belongs to the T10 miniature wedge form factor, a designation that describes the bulb's tubular envelope shape and its wedge-style base, which seats directly into a socket without a separate metal cap.
The 906 operates at 12 volts, consistent with the standard electrical system voltage found in conventional passenger and commercial vehicles.
Its rated wattage is 8W, placing it in the low-power range typical of interior courtesy and reading light applications.
The wedge base design of the T10 means the bulb is held in place by the socket's contact tension rather than a bayonet or screw mechanism, which affects how it is seated and removed.
Because the 906 is an ANSI-standardized type, it is subject to defined tolerances for voltage, wattage, and base geometry, which supports interchangeability among bulbs carrying the same designation from different manufacturers.