Lincoln Navigator Back Up Light Bulb Size

The Lincoln Navigator back up light requires a 921 or 3157 bulb size depending on the model year. The replacement chart covers vehicle production years spanning 1998 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
2007-2014	921
2003-2006	3157
1998-2002	921

Bulb Specifications

Description	Bulb Size
ANSI standard (US & Canada). Wedge bulb (T15). 12V, 16W.	921
ANSI standard (US & Canada). Dual-filament wedge bulb (T25). 12V, 27W/7W.	3157

Other Locations

Additional Notes

The Lincoln Navigator backup light uses one of two bulb types across its model years: the 921 and the 3157, both of which are ANSI-standardized bulbs for the US and Canadian markets.
The 921 is a single-filament T15 wedge bulb rated at 12V and 16W, while the 3157 is a dual-filament T25 wedge bulb rated at 12V with a 27W/7W output across its two filaments.
The dual-filament design of the 3157 means it carries two separate circuits within one bulb, which is a fundamentally different electrical configuration from the single-filament 921.
Because the 921 and 3157 differ in filament count, wattage, and physical size (T15 versus T25), the two bulb types are not interchangeable with one another.
The Lincoln Navigator (1998-2002) uses the 921 bulb for the backup light position.
The 2003-2006 model years require the 3157 bulb, representing a departure from the 921 specification used in earlier and later production years.
The 2007-2014 Lincoln Navigator returns to the 921 bulb specification for the backup light.
A T15 wedge base, as found on the 921, is physically smaller than the T25 wedge base of the 3157, which reinforces that socket compatibility must be confirmed before substitution is attempted.
At 27W on its primary filament, the 3157 draws notably more power than the 16W 921, a relevant consideration when evaluating electrical load on the vehicle's lighting circuit.
Both bulb types operate on a standard 12V automotive circuit, consistent with conventional vehicle electrical systems.