GMC Sierra Trunk Bulb Size

GMC Sierra trunk bulb uses a 912 size for this lighting component across the specified model line. The replacement chart covers vehicle production years spanning 2007 to 2014.

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
2014	912 (Open Trunk, 3500 HD only)
2007-2013	912 (Open Trunk)

Bulb Specifications

Description	Bulb Size
ANSI standard (US & Canada). Wedge bulb (T15). Variant of 921. 12V, 12W.	912

Other Locations

Additional Notes

The 912 is the sole bulb type listed across all trunk bulb specifications for the GMC Sierra in these records.
The 912 bulb is a T15 wedge type, meaning it uses a wedge-shaped base rather than a bayonet or screw fitting, and seats directly into a compatible socket without a separate holder.
It operates at 12 volts and 12 watts, which places it in the low-wattage range typical of interior and cargo lighting applications.
The 912 conforms to ANSI standards recognized in both the United States and Canada, indicating a standardized specification for physical and electrical properties.
The 912 is a variant of the 921 bulb. These two types share the same T15 wedge form factor, though they differ in wattage, which can affect interchangeability depending on socket and circuit tolerances.
The open trunk function is the designated application for the 912 bulb across the 2007-2014 model years covered in these specifications.
For the 2014 GMC Sierra, the 912 trunk bulb specification is noted exclusively for the 3500 HD trim, distinguishing it from the broader application seen in prior model years.