The GMC Canyon back up light utilizes 921 and 3057 bulb sizes depending on the specific version of the vehicle. Available data covers the range from 2004 to 2024.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The GMC Canyon uses two distinct back up light bulb types across its model years: the 921 and the 3057, both of which conform to ANSI standards recognized in the United States and Canada.
The 921 is a single-filament wedge bulb in a T15 form factor, rated at 12 volts and 16 watts.
The 3057 is a dual-filament wedge bulb in a T25 form factor, rated at 12 volts with filaments drawing 27 watts and 7 watts respectively. The dual-filament design allows one filament to serve a different function than the other, though in a back up light application only the relevant filament is used.
The GMC Canyon (2015-2024) uses the 921 bulb for the back up light.
The 2004-2012 Canyon uses the 3057 bulb for the back up light.
The T15 and T25 designations refer to the tubular glass envelope size, with T25 being physically larger than T15. These two bulb types are not interchangeable due to differences in size, wattage, and filament configuration.
The 2017-2019 Canyon carries a separate outer back up light position, which also uses the 921 bulb, making it consistent with the standard back up light fitment for those same years.
The wedge base design on both the 921 and 3057 means neither bulb uses a traditional bayonet or screw base; instead, the base of the glass envelope itself acts as the electrical contact and retention mechanism within the socket.