Triumph TR7 Tail Light Bulb Size

The Triumph TR7 tail light utilizes bulb size 67 and bulb size 97 for the rear illumination system. Available information covers the period from 1975 through 1981 for the specified vehicle components.

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
1979-1981	67
1975-1978	97

Bulb Specifications

Description	Bulb Size
ANSI standard (US & Canada). Single-filament bulb with BA15s bayonet base. Lower wattage variant of 1156. 12V, 8W.	67
ANSI standard (US & Canada). Single-filament bulb with BA15s bayonet base. Variant of 1156. 12V, 13W.	97

Other Locations

Additional Notes

The Triumph TR7 tail light specifications cover the 1975-1981 model years, with two distinct bulb sizes used across that span: the 97 and the 67.
The 97 bulb was fitted to the TR7 from 1975-1978, while the 67 bulb replaced it for the 1979-1981 model years.
Both the 97 and 67 are ANSI-standard single-filament bulbs sharing the BA15s bayonet base, meaning they are physically compatible with the same socket type.
Despite the shared base, the two bulbs differ in wattage: the 97 operates at 12V and 13W, whereas the 67 operates at 12V and 8W, making them non-interchangeable as direct replacements without accounting for the wattage difference.
The 67 is a lower-wattage variant of the 1156 bulb family, and the 97 is also a variant within that same family, both conforming to the BA15s single-contact bayonet fitting standard used widely in North American automotive applications.
The wattage reduction from 13W to 8W between the earlier and later TR7 model years represents a meaningful difference in light output and electrical load on the tail light circuit.