GMC Sprint License Plate Bulb Size

The GMC Sprint license plate light requires 168 and 97 bulb sizes for the specific lighting components. Data for the lighting specifications covers the period from 1971 through 1977.

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
1974-1977	168
1971-1973	97

Bulb Specifications

Description	Bulb Size
ANSI standard (US & Canada). Miniature wedge bulb (T10). 12V, 4.9W.	168
ANSI standard (US & Canada). Single-filament bulb with BA15s bayonet base. Variant of 1156. 12V, 13W.	97

Other Locations

Additional Notes

The GMC Sprint uses two distinct bulb types across its model years for the license plate position: the 168 and the 97.
The 168 is an ANSI-standard miniature wedge bulb in a T10 form factor, rated at 12V and 4.9W, recognized in both the US and Canada.
The T10 wedge base on the 168 requires no locking mechanism, as the bulb is held in place by the tension of the socket itself.
The 97 is an ANSI-standard single-filament bulb with a BA15s bayonet base, rated at 12V and 13W, also recognized in both the US and Canada.
The BA15s designation indicates a single-contact bayonet base with a 15mm collar, which is a distinct physical format from the wedge base of the 168 and is not interchangeable with it.
The 97 is noted as a variant of the 1156, meaning it shares the same BA15s base type but differs in wattage, and the two are not drop-in replacements for each other.
The GMC Sprint (1974-1977) takes the 168 bulb for the license plate position.
The 1971-1973 model years take the 97 bulb instead, reflecting a different socket configuration in the license plate housing for those years.
At 13W, the 97 draws considerably more power than the 4.9W 168, meaning the two bulbs place different electrical loads on the vehicle's lighting circuit and are not functionally equivalent.
Because the 168 uses a wedge base and the 97 uses a bayonet base, physical fitment alone prevents cross-year substitution without socket modification.